Building the Velocity XL-RG
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1/9 (Wednesday) Packing for the trip. The weather will be all over the place. There were even reports of snow nearby. So I'm bringing clothes for warm and not-so-warm. My brother is done with his job in Florida but he's extending his stay a couple days so we can see each other.
1/14 (Monday) I arrived in Sebastian at about 1:30am on Monday morning. A late flight on Sunday was all I could get. And after the drive from Orlando...
My accommodations for the next tree weeks are the Davis House Inn. It's kind of a B&B without the breakfast. Small but cozy.
Monday morning at 9am I was at the Velocity office. After introductions I went out to the shop and saw the plane (or what would become the plane) for the first time.
View from the front (Left side).
View from the front (Right side)
Looking in the back from the right door. The doors have been removed and you can see one inside on the floor. In the back you can see some of the main landing gear retract mechanism.
Looking inside to the front from the right door. Once again, you can see parts of the doors and the wheel from the front landing gear. All the windows are covered to protect them from being scratched during construction.
I was introduced to Rick. He would be one of my guides in getting started on this whole project. I started by doing an inventory of the parts. There are a couple hundred little bags with screws, nuts, bolts, and various other parts that I need to confirm are all there. This took over an hour. The first actual build task is to cutout and remove "the doghouse". The front wing (canard) is mounted in the nose of the aircraft. A part of the fuselage has to be cut out to allow placement of the canard. This piece that is removed is called (for some reason) the doghouse. First, the location of the canard has to be identified. This is accomplished by measuring from specific locations and marking where the canard will be.
Marking the canard location on the right side. The hole is drilled to help locate the position.
Once the canard position is marked, then lines are created using masking tape as a cutting guide.
The result after cutting the doghouse out.
In addition to the doghouse, I also had to cut out access ports in the keel and put in hardpoints for controls. The keel runs the length on the cabin and is between the left and right seats. The control stick is mounted in the keel.
It's hard to visualize it, but this is the keel (upside down). The round opening wasn't there this morning. One of the upcoming tasks is to build a cover. The opening will allow access to the control linkage.
In order to to mount controls to the keel, it is necessary to attach hardpoints to the fiberglass. This creates a strong mounting structure. In this case the hardpoints are created by mounting plywood to the keel and covering it with four layers of fiberglass cloth and epoxy.
Here are two of the hardpoints inside the keel. The white material will be removed once the epoxy cures.
Hours (today/total): 6/6
1/15 (Tuesday) This morning, I started on engine cooling. In a conventional airplane (with the engine in front), there are openings at the front to allow ram air into the engine compartment to cool the engine. Since aircraft engines are air cooled, this is very important. Because the Velocity has a rear mounted engine, cooling is a challenge. The early Velocities used a pair of scoops on top of the fuselage just forward of the engine compartment. The scoops were similar to the hood scoops that you used to see on some high performance cars. The problem with scoops is that they aren't very efficient and since they protrude into the airstream, they cause drag.
So instead of air scoops, we will use NACA Ducts. NACA (National Advisory Committee for Aeronautics) was the precursor of NASA. They discovered that if you create a recessed opening with the right shape, you can get more air with no drag.
So my first task was to cut out the two openings for the NACA ducts to the engine compartment and one for fresh air to the cabin.
From the back looking towards the front at the top of the fuselage. You can see where the two large ducts will be. There's also a smaller fresh air duct in the middle. The tan colored area is the rear of the fuselage (also know as the firewall) where the engine will be mounted. I've also marked the openings in the firewall for the ducts.
Here, I've cut out the engine cooling ducts on top of the fuselage. At this point, I haven't done the fresh air duct or the firewall openings.
After cutting the small NACA duct and the firewall openings, I prepared the surfaces mounted all three ducts with structural epoxy.
One of the things I've got be better at is taking pictures. When I get rolling on a task, I forget to pull the camera out and take pictures. This is why there are no pictures of the installed ducts and flight controls in the keel.
Hours (today/total): 6/12
1/16 (Wednesday)
This morning I installed the two engine cooling NACA ducts and the fresh air duct.
The installed ducts held in place with structural epoxy.
Inside view of the three ducts.
Next I mounted the four hinges to the two elevators. These are mounted at the rear of the canard. When the control stick is pulled back, the elevators are deflected down which increases lift at the canard (airplane goes up).
Two holes are drilled in the hinge. Then structural epoxy is applied to the hinge and it's riveted to the elevator. Finally, another hole is drilled between the two rivets and a screw and nut are used to further hold it in place.
This is one of the hinge brackets riveted, glued and screwed in place.
Here are both elevators with the four hinge brackets on each elevator.
The last task for the day was to create a rectangular opening just forward of the firewall on each side of the fuselage for the main spar. The spar is the primary mounting point for the main wings.
Here are the lines that mark the opening on the left side.
And then, after cutting the opening.
Hours (today/total): 6/18
1/17 (Thursday)
This morning I glassed in the firewall side of the NACA ducts.
This is a view from the firewall of the pilot side NACA ducts with fiberglass/epoxy layups.
I also mounted the landing gear retract hydraulic cylinders. These cylinders will raise and lower the landing gear.
This is the nose gear retract cylinder. I also started installing some of the hydraulic lines.
This is the main gear retract cylinder with some hydraulic lines.
I began installation of the nose gear doors. First the doors are fitted to the opening and then temporarily held in place with globs of bondo (auto body filler).
Nose gear doors (still a single assembly) held in place.
Earlier in the week, I made the nose gear door hinges (four). Now it was time to mount the hinges on the doors. To insure the geometry, a steel rod is run between the two hinges for door. The hinges are then glued in place with epoxy.
Inside view of the nose gear door with hinges in place.
Front right hinge glued in place. A piece of 3/8 inch blue foam is used to make sure the pivot point is the correct distance from the fuselage.
Hours (today/total): 6/24
1/18 (Friday)
This morning I made the nose gear door hinge brackets (eight, two for each hinge. They are mounted to the hinges with bolts. Then, 5-minute epoxy will attach them to the fuselage.
Nose gear doors with hinge brackets glued in place.
Rear hinges and brackets. Each bracket is custom shaped for it's particular position and orientation. To keep track of them, I numbered them (1 - 8) and put a dot on the side facing the front.
Another task was attaching the elevators to the canard. Earlier, I mounted the hinge brackets to the elevator. Now it's time to mount the hinges to the canard.
Here's the canard (it's upside down so you're looking at the bottom) with the two elevators in position. The elevators are held in the approximate position with aluminum I-beams, weights and clamps while we tweak the alignment.
Once the nose gear door hinge brackets were glued in place, I cut the gear doors down the middle and removed them. I finished the day by reinforcing the hinges to the doors with two layers of BID (BI-Directional fiberglass cloth).
Hours (today/total): 7/31
1/19 (Saturday)
Quiet day. The only other people working was a builder that flew down from Canada who was preparing his plane for painting. I began the day by cleaning up the nose gear door hinge layups from last night. Just some light sanding to clean them up.
Next, I started reinforcing the nose gear door hinge brackets. Each tab get two layers of BID on each side. It's close quarters so I decided to the outside of each pair of brackets today and the inside tomorrow. While I was working on the prep, a couple of guys were in for a tour and a demo flight. This was what me and Ann did in June. I figured that I would take a picture or two so they could have a picture.
Future Velocity builder returning from a successful demonstration flight?
Nose gear door hinge brackets with layups. The white fabric looking stuff isn't fiberglass cloth. It's a dacron material that's applied on top of the fiberglass which is peeled off once the epoxy dries. It leaves a smooth finish once it's removed.
Close up of the rear hinge brackets.
Next, I needed to do a layup of two layers of BID at the rear cabin bulkhead.
Inside of the cabin looking aft. At the bottom on either side are two chases (or channels) that will be used to run electrical cables to the engine compartment. The gray that goes halfway around the bottom is structural epoxy that holds the rear cabin bulkhead in place.
Close up at the center bottom of the bulkhead.
The first task is to create a fillet with a "micro-slurry" (epoxy with microscopic bubbles called "micro-balloons" that thicken the epoxy). This rounds over the intersection where the bulkhead meets the fuselage. Then the two layers of BID are applied.
View of bulkhead after the micro-slurry fillet and BID layup. You'll notice that instead of gray, the joint at the bulkhead is now yellowish. That's the micro-slurry.
Center bottom of bulkhead after micro-slurry and BID layup.
Final task for the day is to trim the front access cover to fit in the opening.
Hours (today/total): 6/37
1/20 (Sunday)
Quiet and short day. First I removed the peelply from the outside of the hinge brackets. They came out okay. I thing think they could be better but it's just a "looks" thing.
Rear hinge brackets.
Another view.
I re-drilled the holes before putting in the inside layups. The inside layups were much easier since there were only four instead of eight.
Since the hydraulics cylinders for the main and nose gear are inside the keel, if there is a hydraulic leak, the fluid could penetrate the core of the fuselage beneath the floor. The fix is to coat the area with epoxy. The first step is to mark the area where the keel would be. Then, sand the area. Then mask the area to receive the epoxy. Finally, paint the epoxy on.
The floor with epoxy under the keel area (forward). The dark area is wet epoxy. You can see the centerline mark and (barely) see the lines that show the outside of the keel. The rectangular mark in the center (with the four holes) is where the nose gear retract hydraulic cylinder is mounted. Oh yeah, I had to remove the gear retract hydraulics to do this. I have a feeling that this is going to be a recurring theme... Assemble something only to have to disassemble it for a later task.
Rear view.
I finished the day assembling the rudder/toe brake pedal assembly. I wasn't able to completely assemble them as I'm opting for a different style pedal.
The partially assembled... assembly? Left and right brake cylinders for pilot and co-pilot.
Pilot side brake cylinders.
A note on the "hours". These are hours actually working. Not walking around looking for tools, materials, finding someone to answer a question or trying to find a part in a bunch of boxes. My goal is to see how many hours of actual "work" is required to build this plane.
Hours (today/total): 5/42
1/21 (Monday)
This morning, when I was trimming the inside nose gear door brackets layups, one of them came loose! I checked the other three and I was able to work them loose also. The only thing I can think of is there was some contaminant on the parts. I cleaned the pieces and did the layup again. Next I installed the front section of the keel. This is glued in place using structural adhesive.
Here's the keel from where the pilots seat would be. You can see the bottom of the keel starting at the bottom right of the picture going towards the center. Then it meets the canard bulkhead and follows it up. That corner is about where my feet will be. You can see the gray structural adhesive oozing out. The copper colored cylindrical objects spaced about six inches apart are cleco's (temporary fasteners).
Inside view of the keel where it meets the canard bulkhead. The slot cut into the bulkhead is where the nose landing gear will swing up to the retracted position. Down at the bottom on each side of the keel are small pre-drilled holes. The nose landing gear will pivot at this point.
Then the canard bulkhead had to be reinforced. This time, instead of BID, I had to use Triax (with Triaxial fabric, the threads run in three directions instead of two). A really big job today was mounting the elevator hinges to the canard. Since this will affect the position and motion of the elevator, great care is taken to ensure that the location of the hinges are exactly right.
Since the hinges that attach the elevator to the canard are on the bottom, it's easier to work on it upside down. So here's the bottom of the canard with the attached elevator.
Finally, the main gear retract pulley mounting block is location is reinforced. There will be pulleys here that connect the main landing gear retraction hydraulic cylinder to the landing gear with cables. There's a fair amount of stress in this area so it gets beefed up with about three layer of BID.
Main gear pulley mounting area
Hours (today/total): 6/48
1/22 (Tuesday)
One task day today. This morning the structural adhesive securing the keel was cured. Now the front portion of the keel (where it meets the front bulkhead) has to be reinforced. In one place, there are 8 layers of triax! Once I had prepped the area with sanding and putting in the fillets, it took almost 5 hours to do the layups.
Same area as the first picture on Monday but now with 4 layers of triax.
Same area as the second picture from Monday (inside of keel) but now with three layers of triax at the bottom and 8 layers at the top!
Hours (today/total): 8/56
1/23 (Wednesday)
I was going to start the day mounting the nose landing gear. But it requires drilling a hole through the keel where I did the layups yesterday. But the epoxy had not fully cured yet. So I worked on the main landing gear retraction hardware. This involved putting the pulleys in place, checking the fit, remove, file some of the bulkhead away to allow movement, put the pulleys back in place and repeat... multiple times. This took most of the day. Next, I fitted the nose gear doors and made sure they had free movement. This is the first task I've performed to completion on a articulating part. Very satisfying. I finished the day helping Scott Swing drill eight foot long holes through the canard. This was supposed to be done when the canard was fabricated, but it was overlooked. To drill the holes, a ten foot long, half-inch pipe was used. We cut notches in one end and used a drill to spin the pipe from each end of the canard. Then a one inch hole was created in the middle of the canard where the two holes meet. These holes will be for the wire of the recognition lights that will be on the ends of the canard.
Hours (today/total): 6/62
1/24 (Thursday)
This morning I started by mounting the nose landing gear. The first step is to re-drill the 1/4" holes to one inch. Drilling through 12 layers of triax, 4 layers of BID and 1/4" of plywood is a tedious process... twice.
Pilot side of front of keel with the pivot hole for the nose gear.
After the holes were opened, I had to check and adjust the motion of the landing gear. No adjustment needed... pleasant surprise. I'm told they usually need to be adjusted to align the nose gear. Then I had to drill four holes four each mounting plate and using structural adhesive, glue them in place.
Pilot side of front of keel with the nose gear hardware installed.
Almost ready for a third wheel!
I finished the day by completing the retract pulleys and starting the engine mount reinforcing on the firewall.
Main gear retract pulleys.
Hours (today/total): 6/68
1/25 (Friday)
Short day today. I'm leaving Sebastian at around noon to go home for the weekend. Since the nose gear pivot brackets have cured, I started setting up the nose gear retraction mechanism. Once I had it set up, I had to insure the rear pivot point was correctly located. It was. This is the second mounting location that hasn't required any adjustment. I'm told that they almost always need to be moved a little. This makes me a bit apprehensive. When thing go together too well, I usually think it means that I'm overlooking something. Since the rear retract pivot point seems correctly located, I used epoxy to hold the bushings and mounting plate is place. By then, it was time to head back to the room, shower and drive to Orlando to catch my flight... Which when I got to the airport was delayed about 90 minutes.
Hours (today/total): 3/71
1/28 (Monday)
Returned from a weekend at home Sunday evening. Got started bright and early Monday morning. When I arrived at the shop, Fred had finished painting his plane and had begun putting everything back together.
Frank removing the masking tape from his plane.
The first task was to finish the nose gear install and get the front of the plane off the sawhorse. What seemed to be relatively simple task ended up taking all day. I had to install two brackets. The first one was an alignment bracket that keeps the nose gear centered (left to right) when extended. The difficultly was accessing the the bracket. There's just not that much room inside the keel. Next, I had to reinforce the inside of the keel where it meets the floor. Then, I had to install the upstop bracket. This limits how far the nose gear can extend. Once all of that was finished, I was finally able to install the nose wheel and put the airplane on all three wheels for the first time.
The first milestone!
Hours (today/total): 8/79
1/29 (Tuesday)
Today I turned the plane around to make it easier to install the spar. Normally, the spar is installed before the top fuselage is mated to the bottom. But in a fastbuild, the factory joins the two fuselage parts. This makes installing the spar... challenging. First the spar is slid through the fuselage to check the position. Since the wing is mounted to the spar, the position of the spar is CRITICAL. First it is checked for center. It must extend out the fuselage equally on both sides (you wouldn't want one wing longer than the other, right?). This is pretty easy; just measure each end to the center of the firewall. A nudge, measure, a nudge, measure, etc. Then it is checked for level left-to-right. In this case a small shim was needed on the right side. Then the spar is checked for level front-to-rear. The spar was perfectly level in this direction. Finally, the spar is measured for perpendicular to the centerline. This is done by measuring from the nose of the plane to the left end of the spar and comparing it to the right. Both dimensions were identical! This is starting to make me real nervous. This have been about the forth thing that usually requires a bit of adjusting to make it true.
Then the spar is marked for position and removed. Structural adhesive (did I mention that I'm really starting to hate that stuff?) is thickened and liberally applied. Then we slid the spar back in trying to not smear it all over the place. Once it was back in place we had to recheck all the measurements. It only required a couple of tweaks to get it back in the correct position.
Almost ready for the main wings.
About 100 yards from the hangar is Skydive Sebastian that uses a DeHavilland DHC-6 Twin Otter as a jump plane. Every day we hear the plane take off and about 15 minutes later it lands. So yesterday I stopped by and asked if I could ride along in the right seat. Once the spar was in, I grabbed a spare headset and rode one of the bikes down to the skydiving center. There were about 12 lunatics... er, I mean skydivers in the back. We climbed up to 13,500 feet and then:
After the last jumper was out the pilot made a beeline for the ground.
Here's a view looking straight out the front window. You figure it out.
I finished the day starting the canard placement.
Hours (today/total): 6/85
1/30 (Wednesday)
This morning when I woke up, I logged in and checked the weather... Back home. It was -11 (that's farhrenheit without the windchill) When I walked out the door, I was greeted with this:
And a forecast high of 75.
Today was a one-task day. That means I accomplished only one task. Actually, it was half of a single task. Yesterday I installed the main spar. The main spar is an incredibly over-engineered C-beam that protrudes out each side of the fuselage about 5 feet. The main wings will bolt to this spar so it's very important that it be securely attached to the fuselage. The initial installation is done with structural adhesive. But that's only a start.
This looking towards the back of the fuselage from the inside. The two horizontal lines going left to right with yellowish between is the spar. You can see the gray structural adhesive at the top and bottom where it exits the fuselage. What I have to do is make it become a part of the plane.
The first step is to make a foam bridge from the top of the spar to the top of the main gear bulkhead.
Here's the left side with a piece of divinycell foam bridging the space between the top of the spar and the top of the gear bulkhead.
Here's the right side after I've coated the foam with a slurry of epoxy and microballoons. I've also created fillet in the corners to make an easier radius for the layups.
The same location with all the layups in place. At the location above the spar, there are 10 layers of triax. Some of the layups run down the foam bridge and go almost to the floor. Others go towards the windows. In all, there are 12 separate pieces of triax. And that's just on one side. The light colored patches are peel-ply. Thin dacron that's placed over the layups and makes the surface of the fiberglass smooth. Very important at the edges since without it a lot of sanding is required. This is all I accomplished today... Without stopping for lunch.
I did get all the pieces cut for the other side so tomorrow should be a little faster.
Hours (today/total): 8/93
1/31 (Thursday)
My last full day in Sebastian. I started early this morning to do the left side spar reinforcing layups. No pictures since it's the same thing I did yesterday. But, I was done by lunch. Then I started the pre-departure inventory. Not all of the parts were brought over from the production facility so once I finished the inventory I rode over to the factory and say down with Ken to go over the missing parts. Most of the missing items were already boxed up and ready to ship. A couple items were on backorder. The few remaining missing parts (it's possible that I used them and forgot to mark them off) he just grabbed them out of inventory. No questions asked.
I also found out that the wings would not be ready for transport in two weeks. My plan was to have Travis arrive on 2/18 with the airplane and stay for a couple days to help get started with the strakes. After the two weeks in the middle of February, I'm not going to have much time to dedicate to the build until the 10th of March. Frustrating. But since it's a two year project, three weeks isn't that much of a setback... I guess.
Hours (today/total): 5/98
2/1 (Friday) Short day today. My last day in Sebastian will be spent getting the plane ready for the trip up north. I had to remount the main landing gear so the fuselage can be loaded in the trailer. This involved some trimming of the layups over the past two days.
The final task was to mount the doors.
After that, I went over to the factory to say goodbye. When I was walking through the production facility, I saw my wings.
Left wing upside down. The two wire near the leading edge (one coiled, one hanging down) are for the navigation and communications antennas.
Right wing tip (also upside down). The winglet (basically the rudder) is pointing towards the floor. A lower winglet is in the process of being attached (it's the white part at the top).
On Monday the wings will be sent out to a different shop that will finish the surface and prime them. That should only take two weeks. If it does, I may see the plane on February 17th.
Once I got back to the shop, I loaded the boxes of parts inside the fuselage. At that point, I had done all that I could. I checked in with Travis (who will be transporting the plane north once the wings are done) one last time. Then I said goodbye to Scott and Rick and headed back to the hotel. Took a shower, packed and made the drive to Miami.
Since Ann was working in Miami Thursday and Friday, I changed my ticket to fly out of Miami. As usual, the flight was delayed and we ended up getting home a little after midnight.
Hours (today/total): 2/100
2/14 (Thursday) No news on the delivery. So I'm guessing that the plane won't be showing up on Sunday. The next window for delivery will be 3/10 - 3/21.
2/24 (Sunday) For the past two weeks I've been working on the annual on 6408S* and getting the shop ready so when the plane arrives I can start working on the plane.
One of the things that I need is a heated epoxy cabinet. The epoxies that will be used need to be stored at a relatively narrow temperature range. I knew this, but I thought that since the shop is heated, I wouldn't have to worry about that. When I was in Florida, the shop I was working in kept their epoxy in a heated cabinet. And that was Florida! If the epoxy gets too cold it becomes thick and doesn't flow very well.
I had originally planned on building a cabinet, but while shopping for the heating parts at the local home improvement store, I ran across a simple cabinet for $49.
I lined the inside with 1/2" foil faced insulation.
Then I installed a thermostat and a single fixture for an incandescent light bulb. I was going to put in two fixtures, but I wasn't sure if I needed two so I decided to put in one and add the second if required.
To maintain about 70 - 80 degrees, the 75 watt light bulb is on about 30% of the time.
During construction, I'll need to retract the landing gear from time to time so I'll need some way to support the plane. The front will be easy since a sawhorse will fit under the nose perfectly. For the back (under the wings) I could use Airplane Jacks, but they're rather expensive since they're designed to work under different types of airplanes. While I was down at the factory, I saw a couple different types of fabricated jacks. So here's what I did:
I went to Harbor Freight (I'm really starting to like that store) and picked up a couple 6 ton hydraulic bottle jacks.
Once it's completed, the airplane will only weight about 2,000 pounds so I don't need that much capacity, but these jacks had a longer throw than the 2 ton jacks and they only cost $12 each!
Then I had to make them work for the 37" - 42" span under the wing. So I used some leftover 1/2" plywood from when I built the shop and made a base.
With the jack on top, it's the correct height to raise the wing. I haven't decided how I'm going to secure the jack to the top of the stand. I'm thinking something along the lines of lag bolts with fender (wide) washers around the edge.
Now I'm off the New York City for a week to teach an ACCS class. Then I'm in Downtown Chicago for a week teaching an ICND1 class. After that, I'm hoping Travis and airplane will arrive.
Many people have asked how the airplane is actually shipped. Here's a picture I found showing Travis delivering a Velocity to someone.
3/13 (Thursday) I'm expecting delivery this coming Saturday! The airplane and parts were loaded in the trailer today. Dan Fast who's doing the delivery should be leaving Friday morning with an expected arrival on Saturday. Hopefully there won't be a surprise snow storm.
I've spent some time during the past week moving things around, trying to maximize the available space. I don't see any use for the radial arm saw or joiner so I moved those back in to the garage. I also built a 4' x 7' top on the tablesaw so I can use it for layups.
Here's a picture from the webcam in the shop that shows the top on the tablesaw.
I can't think of anything else I can do until the airplane arrives. One of the first things I'll do is fabricate a system to store the wings on the ceiling. They take up a fair amount of space so getting them suspended overhead will free up a lot of room.
3/15 (Saturday)
We have an airplane. And I think I should have built a bigger shop.
At around 3:30pm, Dan Fast pulled in the driveway.
Because I went ahead and mounted the center wing spar, the fuselage had to be transported almost on it's side.
Me and my son Steve. That's the left wing we're standing in front of.
Dan removing all the straps that held everything in place.
The wings are in.
The left main wheel was removed so that's got to be reinstalled.
It takes four people to get the fuselage off the trailer and on it's own wheels. With me, Dan and Steve, we needed another person, the bigger the better. So we made the call to our good friends Tim and Anne. Here's Tim with Steve probably wondering how this thing is supposed to fly.
Tim's wife Anne brought the necessary celebratory refreshments.
The following so the fuselage coming off the trailer and into the shop.
All done!
My wife Ann (left) with Tim's wife Anne (right). It's got to be good mojo to have a couple hot chicks celebrating the new project, right?
Almost left one part behind. This is the all important fetzer valve cover. You know, it's all about ball bearings these days.
Two more pictures. These are from the web cam.
Before
After
See what I mean? I should have built a bigger shop.
Next, I get to do inventory... again.
3/17 (Monday) I spent Sunday building a cradle and harness then installing screw eyes, pulleys and rope that will allow me the lift the wings up to the ceiling so I can store them out of the way. After building the cradles, me and Steve tried to raise a wing to the ceiling. The balance wasn't right and it kept rotating so the leading edge was pointing down. I also wasn't happy about how it... felt. I just wasn't filled with confidence with that big sucker overhead. So today I did what many other builders have done. I built a mobile rack on wheels. It took about a half day and cost NOTHING. This after spending a whole day and about $50 on hardware for the suspended wing concept. ARRRGH!
I could probably leave them in the shop but it's so much easier to move around without them. So for now they'll stay in the garage and be only a little in the way.
Now that I've got room in the shop, I'll start on the inventory and see what else didn't make it onto the truck.
3/18 (Tuesday) Even with the huge pile o' stuff, it turns out I'm missing a bunch of materials. There are three different types of fiberglass cloth that is used during construction. Uni (unidiredtional, with one layer of fibers that run in a single direction), BID (bidirectional, which is like a regular woven cloth) and triax (triaxial, has three layers of fibers with each running in a different direction). I knew I was missing the BID so Dan Fast told the factory which shipped it out yesterday. But then I discovered that I was also missing the uni, one of the four different types of epoxy and some miscellaneous nuts, bolts, screws and parts. I let the factory know and was told they were going out tomorrow.
3/19 - 3/29 Work for the rest of the week and then diving in Cozumel! (Pictures)
4/1 (Tuesday) I have some time today doing a bit more organizing. Space is a bit tight so I'm trying to get things moved around so that I won't be tripping over stuff. I still haven't figured out where to put all of the parts that I've got laying under the fuselage, but I'll drive off that bridge when I get to it.
All the same parts (nuts, bolts, brackets, fittings, etc.) come in small ziplock bags that are in large ziplock bags for each major assembly (landing gear, fuel system, control system, etc.). It's a real pain digging through 50 little ziplock bags looking for a washer. I did alot of this in Florida at the factory. So I went to Lowes and got some utility boxes just for the hardware. I spent most of the day getting that stuff sorted out.
The next task for the day was building a platform for getting in and out of the fuselage. Without this, climbing in and out gets real old, real fast.
The final job was setting up the epoxy pump. There are about four different types of epoxies used on this project. Most are mixed at a 1:1 ratio. But the epoxy that will be used the most is mixed at a 44:100 ratio. Some people use a scale. That would be fine except it's takes time and it's easy to screw it up. So I purchased a metering pump. It has two tanks and a single lever that will dispense whatever ratio I want. But I had to calibrate it. Which meant I had to pump a sample of the resin and hardener into two separate containers and then weigh them. Then calculate the ratio, adjust the metering and do it again. And again. And again. And again. Until I got it to 44:100.
4/2 (Wednesday) Finally I get to start doing some work! I decided to continue with the last thing I was working on in Florida (Main Landing Gear - MLG). When they build the fuselage, They mount the MLG but only to the point that they can roll the fuselage around. They won't retract. The first task was open up the side of the fuselage so the legs could come up.
Here's the left side main gear leg. You'll notice where the leg exits the fuselage, there's an opening that's a little bigger than the leg itself. When the gear is raised, that leg will swing up. But the hole isn't big enough to allow that which means it has to be... bigger. But how big? Here's my first dilemma: The book doesn't really say. I was expecting a template that you would lay against the side and mark where to cut. Nope. No template. The book just says cut it, not how big. I'm a little nervous cutting when I don't know where to cut so I fussed about this quite a bit. Down in Florida, I would have looked at another plane or asked someone and have been done. Instead, I reread the manual about 30 times, looked at pictures on other builders websites and read the manual again thinking I overlooked something. Finally, I just raised the leg and cut a little. And repeated this maybe 12 times until the leg would raise the correct amount.
This the result of 2 hours of research and 45 minutes of cut, check, cut, check, cut check...
Gear leg up. (I removed the wheel to make it easier to work with.)
Once I knew how big the opening needed to be, the other side took about 15 minutes. This is where the time black hole is going to come from. The whole task is probably slated to take 30 minutes for both sides, but it took me 3 hours.
Next was front seat hardpoints. This is where the front seat are bolted to the floor.
This is a view of the floor looking froward where the pilot seat will be. On the right is the keel and the left (just out of view) is the door opening.
This looking at the floor from the pilot side door. I've laid out the positions of the 2"x2" square hardpoints according to the manual. But wait, I'm a bit taller than the average person.
I decided to make a engineering change and move the seat back an inch.
Because the floor is not flat (lower in the center than on the sides), the outboard hardpoints have to be recessed so the the seat will be level. Here's where one of the outboard hardpoints will go.
The next temporal black hole was how to attach initially. They're going to have two layer of BID over them, but what to stick them on with to hold them in place. One place in the manual said:
"The inboard hardpoints can be installed on the surface and covered with two plies of BID." The other place said "Alphapoxy". Now I haven't had an occasion to use that before but my understanding is that it's a lightweight epoxy. Now there's going to be two layers of BID over top and that's where the strength is going to come from so it probably doesn't make THAT much difference but when in doubt, I'm going to spend time to remove all doubt. So after reading and re-reading, I gave up and called the factory. Turns out it doesn't really matter. ARRGH! Another hour wasted. Maybe I should ship it back to Florida and spend a week every month down there?
The other thing I did today was to redo the lower-rear engine mount reinforcing pads. I did these in Florida, but I wasn't happy with the results. So I removed them and laid up some new ones.
Hours (today/total): 6/106 Probably only 2 hours of "real" work.
4/3 (Thursday) According to the "flow chart" that lists the order of tasks, one of the things I have to do is build the fuel sump. In most planes I've flown, the fuel is fed to the engine from the two fuel tanks (one in each wing) by using a fuel selector. Low-wing airplanes require you to select either the "right" or "left" fuel tank. With these planes, you have remember to switch tanks every 30 minutes or so in order to keep the plane in balance. On the Velocity, a "sump" is used. This is a small (about 2 or 3 gallon) tank that mounted at the bottom of the firewall. Fuel drains from both tanks into the sump which then feeds into the engine. Brilliant!
The fuel sump is pre-molded but is the front is not attached. There are a couple hardpoints for fuel lines that have to be bonded on. So one of the tasks today is to bond one of these hardpoints on. This similar to the hardpoints on the floor for the seats.
While that was setting up, I laid out the a few layers of triax (10" x 10") that would become the nose gear guides. The guides will keep the nose gear centered in the gear well.
Here's a picture of the nose gear retracted. If the nose gear gets turned while it's retracted, the metal "fork" will catch on the edge of the opening and won't be able to extend (I've been there before and it ain't fun!).
While that was setting up, I built a cradle for the rear of the fuselage. Right now, I've got jack stands under the center spar to hold up the back so I could work on the landing gear. But one of the jacks leaks down after a few hours so I have to exchange it for a replacement. That means I either remount the landing gear or come up with another way to support the back of the airplane. I think that I'll need the support the back without using jacks so I cut down one of my old trusty sawhorses that I made about a dozen years ago to fit under the back of the fuselage. But the top of the sawhorse is flat and the bottom of the airplane is curved. So I took some foam and used my (home-made) hot wire cutter to trim the foam to the same shape as the botttom of the fuselage.
Hours (today/total): 3/109
4/4 (Friday)
I installed the second hardpoint in the fuel sump this morning. This one, I'm installing in two steps. The first is bonding it to the tank. The second will be do the two-layer BID layup over top of it. So today, I bonded it to the tank.
Then I started on creating the flange for the access covers for the top of the keel. The keel runs the length of the inside of the fuselage between the left and right seats. The controls for the aileron, elevators and landing gear are housed in the keel. To allow work on the mechanism, access panels were cut into the keel. So they can be attached and removed, flanges have to be made. This is done by covering the area around the access opening with duct tape. The access panels are temporarily glued in place and a couple of layers of BID are put over the panels and the duct tape.
This is the front access cover with the duct tape around the opening.
The rear access cover ready for the flange.
Then I cut the 10" x 10" layup from yesterday to the pieces that will become the nose gear guides. One rectangular piece for each side and a pair triangular pieces to support the guide.
Here are the four pieces all cut and ready for the next step.
Next, I used used some five-minute epoxy to hold the bracing in place. The clamps are holding the angled brace perpendicular to the guide while the epoxy cures.
Here are the two guides with the layups. I'll trim off the excess BID once it cures.
Hours (today/total): 4/113
Now, it's off the Sacramento to teach an ACCS class. Since I won't be done in time to catch the last (non-stop) flight out to get home on Friday, I'll drive over to Minden, NV and spend Friday afternoon getting some time in a sailplane. I did this last year.
Hours (today/total): 4/113
I spent a couple hours Friday (4/11) riding the eastern slope of the Carson range in Nevada. We got towed up to about 7,500 were we released.
Here we are on tow just after taking off. We're actually heading away from the range at this point.
Once we made it to the range, you basically just keep going back and forth riding along looking (feeling, actually) for updrafts. When you find one, you either slow down to stay in it longer or start circling to stay in it.
Heading south along the range.
Turning around to head back to the south.
After about an hour, I had gotten up to about 10,000 feet... Without an engine! Spent another half hour just poking around before heading back. Landing a sailplane is a bit nerve-racking for a powered aircraft pilot. There are no go-arounds when you're landing.
4/13 (Week) The keel access covers I laid up before I left were cured
Rear Keel Access Cover
Front and Read covers removed and ready for triming.
Rear Keel Access Cover trimmed with nutplates installed in keel.
The nose gear guides were also cured, so I trimmed them and temporarily secured them.
Nose gear guides ready for the BID lay-ups.
Nose gear guides with layups.
Nose gear guides installed and cured
Gear up!
I finished building the rudder pedal assembly. In most airplanes, pushing on the rudder pedals only affects the rudder. If you want to activate the brakes, you push on top of the pedal (toe brakes) The original version of the Velocity didn't have toe brakes. If you want to brake, you push the pedal all the way. The first part of the travel activated the rudder and if you pushed further, the brakes would activate. But I'm using a new version that has toe-brakes. And I'm also installing a new style rudder pedal. But they didn't fit exactly right, so I had to make some modifications in order to get a good alignment.
Rudder pedal assembly installed.
To check the positioning, I decided to test them by sitting about where the seat would be. I used some pink foam rigid insulation as a temporary seat. As I'm taller than the average pilot, I think I'm going to build up one of the seats so when I have to check the placement, it will be more accurate.
During the past week, I've been working on the sump quite a bit. After getting the hardpoints installed, I've been sanding the inside and spreading epoxy to make a smooth surface. The inside was incredibly coarse. I probably put 3-4 coats of epoxy down (and sanding in between). But just as I think I'm ready to drill and tap for the fuel lines, I discover two "minor" problems.
Inside of firewall. The two squares with the "X" is where an engine mount bolt will be.
Same view but with the tank in place. How do you get to the bolts if the tank is in the way? Or how do you mount the tank if the bolts are in the way?
I've got a call in to the factory to find out the best way to work around the issue.
Hours (this week/total): 20/133
4/20 (Week) I found out how to resolve the two sump tank issues.
Instead of mounting the two feed lines on the top front of the tank, they'll have to go on the side. Which means adding two more hardpoints for the fuel lines.
As for the engine mount bolt issue, a somewhat more... Neanderthal solution is called for... Check it out:
Before
After. Elegant, huh?
Another view. Won't hold much fuel like that.
New corner installed.
I covered the inside of the corners with two layers of BID.
Next, came the nose access cover. This is how you get quick access to the nose area.
The opening. You can see one of the nose gear guides.
With the cover in place
The manual says to drill four holes for screws in the corners. But I've see some other methods that use two screws and some that use none. One of the solutions is to build a "J" hinge for the front. Then you can put two screws at the rear or even a hidden latch. The thing I don't like about that is when you have the cover open, it's sticking pretty much straight up and I think that would leave it in the way. My plan is to use a similar mechanism but not let it pivot. It'll just hold the front in place. That way, when you need access to the nose, the cover can be completely removed.
Bottom view of the cover with the "Johnston hooks".
Inside view looking forward. I'll glue some tabs where the hooks contact the inside skin to make it nice and tight. Then I can decide how to secure the back.
The flow chart also said to mount the instrument panel. This seems a bit premature, but hopefully the person that wrote the manual knows what they're doing.
The instrument panel is supposed to be 21" aft of the canard bulkhead (That's the bulkhead that the rudder pedals are mounted to). To make sure I get the right location, I marked a couple 3/4" x pieces of wood and clamped them to the canard bulkhead. This will give me the right distance.
Then I tried to put the panel in. Tried is the operative word. It's made oversized so I have to trim it to fit. Which means put it in as far as possible and mark where it binds, pull it out, trim and repeat. And repeat, and repeat.
Once I got the panel to fit in the correct location, I applied duct tape to the back edges. I then applied a 2 BID layup on the left, right and bottom middle of the panel and let it cure overnight. In the morning, I drilled holes through the panel where the layups were.
New mounting tabs.
Panel temporarily held in place with clecos.
Seat surprise! I decided to build up at least one seat that I can use for testing. Basically, I have a seat bottom and a seatback. I have to screw these to hinges. The hinges allow the seatback to fold forward so people can get in a out of the back seat. I've got a new style hinge. I'm rapidly coming to the conclusion that new=a lot more work. The old style had a fixed upright position. Which means that you had to decide when you were building the seat. The new style lets you adjust it at anytime, just like a car seat.
Here's the new style hinge.
Old style hinge.
But the problem is that I couldn't get the seatback to fit the hinge. I tried and tried. I tried all sorts of different ways of getting it to fit. It just wouldn't. Then I started looking at other peoples build sites. That's when I discovered that nobody else have seat hinges like mine.
So I called the factory. They said I would have to send the seatbacks back down to Florida to be modified.
Then I went to mount the hydraulic pump assembly. This is an electric motor mounted to a pump which is mounted to a reservoir. But when I tried to mount it, the tabs didn't meet the bulkhead... The reservoir was in the way.
Here you can see the two mounting holes that I think should fit against the bulkhead. I checked pictures from some other builders and it seems I'm right.
Here's another builders bulkhead with attached pump.
But after I emailed the factory, I was told that I need a bracket. So now I've got to wait for that.
5/12 (Tuesday) Between work and building, I haven't updated in while. Sorry.
After spending the last two weeks on the road, I didn't get much building done. I did get some building related work done. Malcolm Collier of Hangar 18 fame is a professional builder who works with builders that don't have much available time to build. His work is some of the finest and he has made some impressive innovations to the Velocity design. So after class was done on Friday, I flew over to Greenville, SC and hung out with Malcolm. I got some good ideas and some great tips. Then I had to spend the next week in New York City.
Once I got back from NYC, I resumed building. One of my tasks was getting the main gear positioned and aligned so I could permanently install the pivot bushings. Now consider that this airplane (when taking off and landing) is going to be moving down a runway at about 70 MPH. So the wheels should be in exactly the right location. Here's another situation where the manual doesn't go into a lot of detail.
The gear legs should be symmetrical and a line between the wheels should be perpendicular to the longitudinal axis. But how to determine that?
Here's what I did. First, I leveled the plane front the rear and side to side. Then using a plumb-bob, I marked the centerline of the plane at the front and rear on the floor and drew a line between the two points. So now there's a line on the floor from the front to the rear of the fuselage.
Next I ran a string from one of the wheel mounting holes on the right gear leg to the corresponding hole on the left gear leg. The I measured the distance between the two gear legs and put a mark on the string at the halfway point.
Then, using the plumb-bob from the mark, I adjusted the gear legs until the mark on the string was in the middle.
I actually put two marks on the string so I could easily see when the plumb-bob string was in the middle.
Next I had to get the gear legs positioned front to rear. For that, I used a laser. I pointed the laser through one of the wheel mounting holes on the gear leg so that it went through the same hole on the other leg.
Then, I moved the the plumb-bob until it was hit by the laser.
Here's the laser hitting the plumb-bob line.
I then put a mark on the floor. I did this at a couple locations between the gear legs. Next I drew a line connecting the dots.
Checking the location of the line just to make sure nothing changed.
Finally, I just had to check that the centerline and the line between the gear legs was perpendicular and adjust if necessary.
Now the whole operation start to finish was about an hour but I must have spent half the day figuring out how to do it in the first place.
Next, I had to install and reinforce the transverse bulkhead. This relatively small piece connects the firewall to the main gear bulkhead. The plans call for the piece made to made from foam and covered with two layers of triax. I felt that using some plywood wouldn't add much weight and would add strength. To determine the correct size, I used cardboard and trimmed it until it fit. Then I transferred the shape to a piece of plywood.
Plywood transverse bulkhead
Then I had to determine the shape of the triax fiberglass that would cover it. I used small pieces of posterboard and taped them together.
This is the outside triax template.
Here's the outside view of the transverse bulkhead with the layup in place.
Inside view on the transverse bulkhead.
Time to make an engineering change. The oil is cooled with two oil coolers. The primary oil cooler is in the back with the engine. There's a secondary oil cooler in the nose that's used to cool engine oil and provide cabin heat. A NACA duct is installed in the side of the nose, the oil cooler is mounted and another duct exits the bottom. Two 1 1/2" tubes are inserted into the exit duct that supply warm(er) air to the cabin area. A small flap/diverter is installed in after the tubes that would block the air from exiting outside and instead directs it to the cabin. Here's the problem: At cruise speed, the air is forced through the oil cooler at an incredible rate. And in the winter, the air at cruise altitude can 20 - 30 below zero. Given that, I think the oil cooler would increase the temperature of the outside air maybe 50 degrees. Which means that the cabin would be "heated" with 30 - 40 degree air.
So here's the plan: I'll put an additional flap between the NACA duct and the oil cooler to block the outside air. Then run a return line from the cabin to the oil cooler. That way I'll be heating inside air that already warm.
This plan requires fabricating almost all the parts.
Here's the plan view. On paper.
I'll make a form out of foam and cover it with fiberglass. I used a spreadsheet based the formula for the NACA design developed by the NASA predecessor in the 1950's.
Here's the form made from glued blocks of foam.
This is the result. Needs a little cleanup but not bad.
This is the duct for the air after it goes through the oil cooler and then out the bottom of the fuselage. I had to make a flange where the oil cooler mounts to it. Because the geometry of the design is different, I had to make a slight modification to the opening so it would cover the entire oil cooler.
Now it's time cut the opening for the NACA duct. This part always drives me nuts! I'm cutting a hole in the airplane! What if I cut it wrong? Oh well.
Duct cleaned up with the flap that blocks outside air.
Flap open. You can see the inside return air port.
The flap mounts to the bolt that is filed down, drilled and tapped.
Here's the mark for the opening
Inside view where the duct will go.
After the cut. Hope it's in the right place.
Duct installed.
Inside view of the installed duct.
The whole assembly installed with oil cooler.
View from the outside. You can see the oil cooler inside.
Same view with the door closed block outside air from the cooler.
Partially disassembled. These two tube will have flexible tubing that supply warm air to the pilot and co-pilot side of the cabin. Here the flap is closed that will force warm air into the cabin.
Same view with the flap open that blocks the cabin supply lines and exhausts the air outside.
Once the tranverse bulkheads were in and the layups were complete, it was time to permanently install the main gear bushings. The main landing gear is located between the firewall (at the very rear of the fuselage) and the main gear bulkhead. There is a hold drilled in the main gear leg where a steel sleeve is installed. A bolt goes through the two bulkheads and through the landing gear leg. The gear then pivots on this bolt which allows it to be raised to the retracted position. Where the bolt goes through the two bulkheads, an aluminum bushing is installed as a bearing point. Up until now, all these components were present, but not permanently installed.
Left main gear leg viewed from the inside. This is before the transverse bulkhead was installed. But you can see the gear leg, pivot bolt and forward bushing.
View from the inside showing the bolt and aluminum bushing temporarily installed.
My first order of business is to get the bushings in place. I removed the bolts, pulled the bushings, and coated the contact surfaces with structural adhesive. Then put everything back together and lightly tighten down the nuts. The manual says to also glue the sleeves in the gear leg at this time, but I was nervous that I wouldn't get everything in position before things started setting up.
Once the bushing were in place, I pulled everything apart and used structural adhesive on the steel sleeves in the gear legs and put everything back together again. That's when I discovered... a glitch.
Turns out when I tightened everything down in the previous step while the bushing were setting up, I didn't get the nut very tight. Since the bolt head is on the outside and the nut is on the inside, I couldn't hold a wrench on both. The result was that the nut wasn't tightened enough. This resulted in an excessive space between the two bushings which allowed the gear leg to move front to rear. Since the sleeves had adhesive on them, I decided to position the gear leg as best I could and figure out what to do next.
I checked with the factory and they said I could either stuff some washers in or I could remove the bushings and put them back in. This was a bit of a surprise since I thought the adhesive was "permanent". Turns out that if the adhesive is heated to the right temperature, it's possible to remove the bushings. I removed the left gear again, put a soldering iron in the bushings for about 15 - 20 minutes and using a home-made press they popped right out. Then I cleaned up the openings. I hoped that I would be able to glue the bushings back in and be finished. But the steel sleeve wasn't where I wanted it. In hindsight, I should have pulled the gear leg when I discovered the gap, removed the sleeve from the gear leg and cleaned off the uncured adhesive.
So now I had to remove the sleeve. Which means sticking a soldering iron in the sleeve, waiting 20 - 30 minutes and with Steve's help, we got the sleeve out.
Then I covered the bushings with adhesive and bolted everything back together. Once that cured, I removed the gear leg, put adhesive on the sleeve and put everything back together.
Once that one done, I had to put a two layer triax layup on the back of the firewall over the bushings and over the front of the main gear bulkhead over the bushings.
All this took about a week. It should have a taken a couple hours. Pretty steep learning curve.
Next was reinforcing the doghouse and doghouse opening. The "doghouse", by the way, was my first clue that things were not going to be easy. If you look at "Task 2" on the task list, you'll notice it says "Cut out Doghouse". In the actual task list, it also says that task is in "Chapter 6". But it doesn't say WHERE in Chapter 6. There are 31 8 1/2 x 14 pages in chapter 6 with about 41 separate tasks. Some of these tasks do not apply since they were already done during the pre-build done at the factory (these steps are not identified in the manual so you have to read through another list to find out that it doesn't apply to you). So the only way to find the steps involved with this task is to read through the entire chapter.
I eventually found the section on page 35. Which means the very fist step in building the airplane was in Chapter 6 on Page 35.
Go figure.
Anyway, I cut the doghouse out back in January. The reinforcing is supposed to be accomplished by first digging out some of the foam between the inner and outer skin and filling it with a mixture of epoxy and cab-o-sil. Cab-o-sil (called "cabo") is an additive that is mixed with epoxy to make it thick.
Here's the front of the doghouse opening after I removed some of the foam between the inner and outer skins.
Here's where I made another "engineering change". Malcolm at Hangar 18 doesn't fill the groove with just epoxy and cabo. He lays in a bundle of glass fibers the entire length on the groove. This creates an extremely strong arch. The only problem is that the fiberglass strands that he uses come in very large quantities that I would only need a fraction of. So I took some unidirectional fiberglass cloth (in unidirectional cloth, the fiber run in one direction only and are held in place with some small cross fibers) and stripped out the fibers by hand until I had enough to do both sides of the opening and both sides of the doghouse.
Here are the four bundles of glass fibers. Two short ones for the front and two longer ones for the rear.
Then it was time to saturate the glass with epoxy and embed it in the groove.
One of the bundles being saturated in epoxy.
Close up of the end.
Rear opening with epoxy/cabo mix ready for the "horsey tail".
Once the fiberglass strands were in place I covered them with a layer of BID. After it cured, I needed to get the space between the canard and fuselage consistent. So I covered the doghouse side with a layer of duct tape and mushed in an epoxy/cabo mix in between. Afterwards, I pulled the tape off and I had a perfectly even gap between the doghouse and the fuselage.
Finished edge.
Next it was time to finish the sump tank. Previously, I had chopped off the bottom corners and put on some flat pieces on fiberglass to allow for the engine mounting bolts. Then I learned that the fuel fittings that connect the main tanks to the sump will interfere with the landing gear. The fix is to move them to the side of the tank. This required installing additional hardpoints for the relocated fuel fittings.
Once that was done I was able to proceed with sealing the inside of the tank. This step is not required by the manual. Current aviation fuel will not breakdown the epoxy. However, it's possible that future aviation fuels may not be... compatible with the epoxy. The reason behind not requiring the sump tank to be sealed is you could always build a new sump tank should aviation fuels change. I'd rather not build another sump tank so I decided to seal this one. I also wanted some practice with the sealing epoxy. It's called Jeffco and it's extremely touchy. It has a rather short pot life and can get really hot if you mix too much at once.
First I cut the back of the sump tank to the correct shape and size. Then I sanded both the tank and back.
Sump tank ready for Jeffco.
Back of sump tank ready for Jeffco.
I wasn't sure how much to mix so I guessed. I guessed wrong. With Jeffco, when starts to kick, it gets hot. the hotter it gets, the faster it kicks. The faster it kicks, the hotter it gets. The more you've got...
Melted the cup!
I did get the first coat on before it started to melt the cup.
Then once it got tacky, I mixed up a much smaller batch and put on the second coat.
Back cover of sealed sump tank.
Inside of sealed sump tank.
After the Jeffco cured, I mixed up another batch and mixed in some cabo to make a think cake frosting like consistency. I put this mixture in a ziplock bag and clipped the corner off. Then I squeezed it out on the perimeter on the back. Then the sump tank goes on until it cures.
Once it cures, I covered the seam with two layers of bid. Then I made the mounting tabs. At this point, the sump tank is done. I still need to test it plugging the openings and submerge it in water to make sure there are no leaks.
Finished sump tank!
Next are the elevators. Okay, so there's a small wing on the front. This is the canard. On the trailing edge of the canard is a moveable surface. This is called the elevator. By changing the position of the elevator, the amount of lift that the canard creates can be changed.
Here's a picture of the canard and elevator from January when I was installing the hinges. In this picture, the elevator is upside down. So this is looking at the bottom. On the right is the canard. On the left you can see the two elevators (left one on the bottom of the picture, right one on the top). The two elevators will move as one. They are connected with the white tubing in between (called the elevator torque tube). At the time this picture was taken, the torque tube is not attached to the elevator. That's what I need to do next.
Now the position of the torque tube is rather precise. If it's not in the exact correct position, instead of rotating it could bind and not move freely. So to locate the correct position, I decided to use my handy laser again. The problem is that the "tab" on the end is not perfectly aligned with the tube so I can't just align everything to the center of the tab. I need it aligned to the center of the torque tube. So here's what I did: I made a jig to allow me to rotate the torque tube so I could mark the exact center of the tube on the tab.
Here's the torque tube end with the marks identifying the center. The jig wouldn't let me make a complete circle, but I was able to adequately mark the center
Then I mounted the elevators and torque tubes on the canard. I left the three inboard hinge screws out. I put the laser so that it would shine through the holes on the three hinges without screws.
My setup with the laser.
Here's the laser shooting through the first hinge.
A little more to the right will have it dead-solid-perfect.
Once it's in position, I drilled through the elevator and torque tube. Then put in the screw and nut.
Now that the elevator torque tube has been positioned, I'm going to get the canard mounts installed. There are a couple steps that the manual has being done all at once. But I'm a little concerned about doing multiple steps at the same time of I'm going to do this separate steps. The first step is to make sure the canard fits in the opening, is level (side-to-side), has the correct incidence (level front-to-rear) and is perpendicular to the centerline of the fuselage
The first task is to get fuselage level left-to-right and front-to-rear. Placing a level on the firewall showed that I was level front-to-rear. Side-to-side level is determined using the center spar (what the wings mount to). The center spar sticks out about 5 feet on either side of the fuselage. But a two to four foot section of the top of the spar is not necessarily representative of the entire span. So first I tried running a string from one end of the spar to the other and using a little bubble level that hangs from the string. But after fussing with that for a while, I kept getting variations. So I gave up on the easy way and used a water level. A water level is a long piece of clear hose filled with water. You put one end of the hose at the end of the center spar and the other end of the hose at the other. When the water level is at the same point of the spar, it's level. But with one person, there's a BUNCH of walking back and forth until it's just right.
Looking from the right side, you can see where I have one end of the water level clamped to the center spar.
Here's a closeup of the right side. Notice the level of the water is aligned with the top of the spar.
Next, I check the side-to-side level of the canard. First, I used my four foot construction level to get it close. Then I opened the garage door and walked about 20 feet from the back of the plane. Using the top of the right end of the center spar, I raised and lowered my head until I could just see the top of the right end of the canard. Then I looked to the left to check that the canard was the same as the center spar. It wasn't. So I sanded the bed that the canard sits on one side and shimmed a bit on the other. Then it's back outside to eyeball it again. After a dozen or so iterations, it was perfect.
Looking from the back, you can just barely see the canard above the spar. It looks like a little white line. In fact, you can see a bit more white (the canard) on the right side than you can on the left.
Lowering the camera just a little and now you can't see any canard... Well, there is just a tiny bit on the far right.
Then I had to check the incidence. There's a gauge that sits on top the canard and you put a level on that. When the gauge is level, the incidence is correct. So I had to do some tweaking to get the incidence right. But screwed up the level (side-to-side). So I had to fix that which screwed up the incidence. After a while, I had both correctly set.
Looking from the fuselage out along the canard. On the top is the "incidence gauge". When the top of the gauge is level, the canard will be at the correct angle of attack. Resting on top of the gauge is my combination square/level.
A close up of the level. The front is a bit low (or the back is too high). A little shimming and...
Perfect!
Then I had to check that the canard was square to the fuselage centerline. This is done by measuring from the left end of the spar to the left end of the canard. Then you do the same on the right side. Since the spar is square, the two sides will be the same if the canard is perpendicular (it wasn't). So I had to make some adjustments. Which messed up the two previous adjustments. So I got the side-to-side level, got the incidence right. Then I had to get the side-to-side level fixed (again) which messed up the incidence. Once I got those to right, I had to tweak the perpendicular setting which messed up the other two.
spar-canard measurement
I probably spent about two hours getting this right. And keep in mind that this was just to make sure that I could get all three axis correct. Once I was sure I could do this without any sanding or grinding of anything, it was time for the first major step. The canard rests on the fuselage at the bottom of the opening. I removed some foam from between the inner and outer skins.
Left side of the fuselage where the canard rests.
I filled the space between the inner and outer skin with a mixture of epoxy, milled fiber (for strength) and cab-o-sil (for thickness). Then I put a layer of thin aluminum tape of the bottom of the canard to prevent the canard from being permanently attached to the fuselage.
Now it was time for the hard part. I lowered the canard in place, the epoxy squished out of the space between the canard and fuselage. But now I've got the get the canard set correctly. So I spent the next hour or so adjusting, readjusting, readjusting, readjusting, readjusting, etc., etc., etc. It's a good thing the epoxy takes hours to set up!
The following day I was ready to install the canard tab mounting bushings. On the bottom of the canard are two mounting tabs that are the primary means of attaching the canard to the fuselage.
These tabs fit up against the "canard bulkhead" which you can see in the previous picture. It's the part that goes across the fuselage under where the canard sits.
One of the canard mounting tabs
First I removed and then reinstalled the canard and then checked all the measurements again just to make sure the canard would in the exact correct position... And it was. Then I drilled a 1/4" hole through the hole in the tab through the canard bulkhead. Then I removed the canard. I opened up the hole in the canard bulkhead to 1-1/4" so the bushing would fit. Then I enlarged the hole in the tab to 5/16" so I could fit the bolt through.
Then I applied Vaseline to the bolts, nuts, washers and canard tabs. Finally, I reinstalled the canard, coated the bushing with structural adhesive, put the bolts in and tightened the nuts. Then checked the alignments of the canard (again).
Right side canard tab.
Left side canard tab. The yellow tape under the bolts is my way of indicating which bolts are temporary. In most locations, locking nuts are used. They are basically single use nuts so if you remove them, you should throw them away. In many locations, things will be coming back apart so I use non-locking hardware. This is how I'll remember.
The next morning I removed the bolts, pulled out the canard and then reinstalled it again... And checked the alignment again.
Canard bushing in place.
There was one final part of the transverse bulkhead that I needed to finish and that was the layup just forward of the center spar. Fortunately, this one is done with BID instead of triax.
Looking in from the right side. On the left is the center spar and you can see where it exits the left side around the top-center of the picture. The BID layup start at the bottom of the spar, goes forward, then up the main gear bulkhead, up the "slant bulkhead" (then out of the picture).
Looking up at the bottom of the "slant bulkhead" and then you can (barely) see where it turns aft and stops at the top of the center spar. I had to use some clothes pins to hold the layup in place. Gravity, you know.
Back to the canard. Now that the canard is mounted, I needed to get the doghouse to fit.
Not very aerodynamic.
I used a compass to determine the approximate line to cut on but as usual, I chickened out. I was afraid that I would cut off too much. So I cut a bit shy of the line. Then put it back on, marked it again, took it off, cut a little closer, put it back on, marked it again, etc., etc., etc. And a few hours later...
Doghouse in place.
Now I had to build the canard torsion tabs. These are additional layups that prevent the canard from twisting. First, I had to locate on the canard where the inside of the doghouse will be.
Here I've drawn a line to indicate where the doghouse is. I then sanded down the white filler on the inside. Under where the doghouse would touch the canard, I put down a layer of tape. Then Bondo is used to TEMPORARILY hold the doghouse to the canard. That's right, Bondo. As in auto body filler. I works great as a temporary means on holding parts together.
Then the canard and doghouse are removed as one.
Next, I had to build a form for the canard torsion tabs.
Canard/doghouse on the workbench. You can see two dabs of bondo where the doghouse meets the canard. The wood on the fore and aft outboard parts of the doghouse are the forms that create the torsion tabs.
Duct tape prevents the layups from permanently joining the canard to the doghouse.
Creating a radius with epoxy/cab-o-sil. Triax doen NOT make sharp turns well.
Then as many as six layers of triax are used to create the tabs. Once it cures, remove the forms, sand off the bondo and...
Finished canard torsion tabs.
Once the canard torsion tabs were done, they are covered with duct tape. The canard is reinstalled back in the plane and wood is used to create a form for the forward and aft torsion tabs.
Left rear torsion tab.
Left front torsion tab
Elevator torque tube cutout.
From the right side looking at the canard installed without the elevator. You can see three of the elevator hinges. But there's no opening on the fuselage for the elevator torque tube.
The first thing is to locate where that hole is supposed to be. Some people eyeball it. Some have used string through the hinge holes. But I got a better idea... LASER!
I setup my laser out beyond the end of the canard and adjusted it some that it was shooting a vertical line through the hinge holes.
View of the outboard hinges with the laser on.
Right side of the fuselage. The center mark is what passed through all the hinge holes. With a pencil, I put a vertical mark where the laser hit.
Then I rotated the laser and repeated with a horizontal line. I put a pencil mark there as well.
"X", or rather "+" marks the spot.
Then just to make sure, I changed the laser to a point to re-check.
Drill a small hole to get started
Then make it bigger
Then use the 1" hole saw for the final opening. You can see the hole on the other side as well.
Since the torque tube is attached to the elevator, I have to cut away the area above the hole I just drilled.
Marking the cut lines.
After cutting.
Lights!
The Velocity comes with a single landing/taxi light mounted in the nose. Currently, the light that comes with the kit is a halogen light. They're working on an HID (Xenon High Intensity Discharge) upgrade. HID lights are used some of the newer cars today. These are the really bright lights that have a bluish tint. They are extremely bright.
I want to put these in either the main wingtips or the ends of the canard for a couple of reasons:
1) More light. There's no such thing as too much light when you're landing at night.
2) Visibility... As in being seen.
When you're flying, you are responsible for making sure you don't run into another airplane. You'd be amazed how hard it is to see another airplane sometimes. I've been flying on an IFR flightplan when ATC advises me of another aircraft nearby sometimes as close as 3 miles and I never saw it.
I was flying into Dekalb (KDKB) one day and saw a pair of flashing lights in the distance. It was an airplane MILES away that was inbound for landing!!! After it landed, I spoke with the owner who told me that he had recently installed HID lights in the wingtips and added a pulsing system and made the lights flash in an alternating pattern.
So this would definitely be a modification.
Since the ends of the main wing are where the winglets attach, I decided that I didn't want to weaken that wings there. So I went with the canard tips. First I would have to cut openings where I could recess the lights. In order to do that, I needed the lights to know how big an opening I would need. Some builders use the lights from a car but I needed really small lights that would fit in the canard and I wanted to stick with aircraft grade components. So I bought a pair of lights from Xevison.
Now that I've got the lights, I can layout the cut lines on the canard and make the cut. Once again, it makes me really nervous cutting into an airplane. Once I had the canard skin cut, then I just had to remove the foam.
I needed a way to mount the lights securely that would also allow me to remove them for maintenance. So I cut a pair of small aluminum angle brackets for each light.
Inboard bracket for right light.
Cutout for bracket.
Inboard bracket glued in place.
Both brackets glued in place for right light.
Next I covered the foam with BID and epoxy. Once that was done, I drilled a hole in each bracket and tapped in for 4-40 screws.
The lights will need a plexiglass cover. To be aerodynamic, it will need the same contour as the canard. To make these, I need a mold of the canard so I can make the lens cover.
The first step is to cover the canard with a release agent so the polyester resin that I use to make the mold doesn't become a permanent part of the wing.
Section of the canard with the release agent applied.
The mold is made by applying two layers of fiberglass mat with a polyester resin. Polyester resin is used instead of epoxy because the heat from the heated plexiglass would cause the mold to deform if epoxy resin is used.
After the two layers of mat come one layer of BID, two layers of triax, one layer of bid and two layers mat. One of the challenges is keeping everything cool. Polyester resin can get very hot when curing. And the more you use, the hotter it gets. So I spread out the layers over a whole day and used a fan whenever the area started getting too warm.
Just about done.
Once the resin cured, I needed to build a stand for the mold. The stand also adds some structure to the mold.
Lens mold with stand.
The release agent is water soluble. So to remove it, I flipped the elevator over so that the mold was on the bottom. Then I used a spray bottle and squirted water around the mold/canard. After a few minutes and a little persuading, the mold fell right off the canard.
The final product.
A perfect shape.
To get the plexiglass in the correct shape, I need a way to force it out at the top. Otherwise it'll curl in. So I took a scrap piece of 2x6 and planed it to the right shape.
There are some slight imperfections in the mold and the inside piece is far from the correct shape. I solve this problem with an old Aircraft Tool Supply catalog. The slick paper makes for a perfect release material and the rest of the catalog smoothes the shape of the inside mold.
Ready for the Plexiglass.
Next it was time to make the lenses. I obviously need one for each light, but while I making them, I may as well make a couple spares. I also need an extra one that I'll cut in half so I can make the flanges that the lens will attach to.
So I got some 3/16" plexiglass from McMaster-Carr and cut it to about 8"x8". The actual lens will be a bit smaller, but since there's no way to precisely position the plexi when you're forming it, it needs to be larger than necessary so you can trim it to the correct size.
8x8 piece of plexiglass with the protective paper still on. The paper protects the surface from scratches until you're ready to use it.
To make the lens, I'll heat the plexi to about NO MORE than 370 degrees. I'll start at 340 and move up as needed. I took a piece of coat hanger wire and made a hook for the top of the oven. Then I got a steel spring clip and attached it to one end of the plexi. Once the oven is preheated, I hang the plexi in the oven.
I know it's at the correct temperature when I can poke the bottom of the plexi and it moves easily. Then I QUICKLY pull the plexi from the oven, bend it in two and drop the inside of the form in.
But there's a slight problem. By the time I get the plexi out of the oven and in the mold, it's already too firm to fully contour to the mold. I try a couple more times and end up putting the mold on the open oven door to reduce the time from the oven to the mold. I got a couple pretty good lenses but not good enough.
So I had to recruit my wife. With me positioning the soft plexiglass over the mold and her pushing the inside form in place, we were cranking out perfect lenses every time. Then, I just had to trim them to the correct size.
I took one of the lenses and cut it in half lengthwise. I taped the top half in place and, working from the inside used epoxy/flox/cabo to create a flange (lip) for the lens to rest on. Once it cured, I removed the lens half and taped the bottom half in place the finished the bottom flange.
half lens in place with flange
light opening with lens flange
Test fit of the final result. I'm leaving the bulbs out so as not to break them.
The next step would be putting on the canard tips. But before I could do that, I had to make a slight detour. The wiring for the lights will along the inside of the canard through holes that were drilled through the foam core when I was down in Florida. But at the time, I didn't know how big the connector was. Turns out it's just a little larger than the hole. So I had to make a new, slightly larger drill bit using a piece of 1/2" electrical conduit. I cut a saw-tooth pattern in the end and twisted it through the existing holes and enlarged them a bit.
Canard end before.
The first step is to make a cutout for the elevator counterweights. These weights counteract the weight of the elevator to eliminate downforce caused by the weight of the elevators. The counterweights are recessed in a pocket that I have to create.
First I mark the location of the counterweight pocket.
Then cut it out.
Then glue on the canard tip. The tricky part here is to make sure that both tips (left and right) are symmetrical. For this I used my laser level again. Once I had the canard level, I shot the laser across both tips and adjusted until they were level. This side gave me some problems so I had to "persuade" it with a clamp until the glue set.
This side only needed a little tape to stay in place.
This is were I discovered a minor glitch. When I was drilling the holes for the screw that attaches the elevator to the torque tube, it turns out that my alignment was more precise than the canard itself. As a result, the elevators are not perfectly aligned. I didn't notice it before because there was no reference. With the canard tips on, it was obvious that one elevator was lower than the other. Not a huge problem. I just need a new aluminum bushing that I'll redrill. So until I get that, I'll put the remaining canard tip work aside.
I still need to finish the canard-to-fuselage and doghouse-to-canard joining. Earlier, I drilled the hole for the elevator torque tube and opened up the area.
Since the area was curved, I was worried that a flat piece wouldn't work. So I covered an area of the fuselage with the same curvature with duct tape. Then I laid out a layer of BID, a piece of divincel foam and another layer of BID. Once it cured, I had the stock to build the filler. Then I cut it to fit, glued it to the bottom of the canard. Once the glue set, I completed it with a couple layers of BID.
The bottom of this filler now has to be perfectly fitted to the fuselage. So I cut a little smaller than required. Covered the fuselage area with duct tape, filled the bottom with epoxy/cabo and then lowered the canard in place. Once it cured, I have a perfect fit between the filler piece and the fuselage.
Fuselage taped over ready for the filler piece.
picture of lower canard Lower canard-fuselage.
Now it's time to tackle the top of the canard. Basically, it's the same as the bottom. First I mount the canard on the fuselage then covered the top of the canard where the doghouse rests with duct tape. Then fill the bottom of the doghouse with epoxy/cabo and lower the doghouse onto the canard.
Epoxy/Cabo mix squishing out.
Once it cures, a quick cleanup of the excess epoxy and I've got a perfect fit.
Now for another departure from the plans. The manual has the doghouse being attached to the canard torsion tabs with four screws. There's nothing wrong with this approach, but there's another way that doesn't use any externally visible fasteners.
First I cut a length of piano hinge a little less than the length of the opening. Then I drill four holes through the hinge and tab.
Here the hinge is temporarily held in place with cleco's.
Then I countersink the screw holes.
Apply some structural adhesive and screw it in place. I've got duct tape on the hinge to keep the two side from becoming permanently attached to each other.
Inside view.
Then I drilled four holes through the top part of the hinge and the doghouse. I then drilled out the four holes to about 1/2" and filled the area with epoxy/milled fiber/cabo. Once it cured, the drilled it out again.
I covered the top half of the hinge with structural adhesive, lowed the doghouse in place and inserted bolts though the holes from the outside into the hinge. Put the nuts on and tightened. I also filled the holes on the outside of the doghouse.
When it was done, this is what the top of the inside of the doghouse looks like.
When I put the doghouse on, this is what it looks like (on the inside) just before it's all the on.
Here it is all the way in position.
Then I just slide the hingepin in place and the doghouse is held in place with no externally visible fasteners.
From the outside.
According to this guy outside on the driveway, it shouldn't be too bad a winter.
Not much going on this month. Lots of travel, not much time at home.
I did get the new torque tube bushings. Now my problem is how to drill a hole through the new bushing with the exact same alignment.
Here's the deal: The bushing is a cylindrical piece of aluminum that fits inside a round opening on the end of the elevator. Originally, when everything was positioned, I drilled a hole through the elevator and the bushing at the same time. The hole wasn't EXACTLY through center, but it was close enough.
Now I've got a new bushing that I have to drill a hole in. But I've already got holes (top and bottom) in the elevator. Obviously, when I put the new bushing in I'll use the top hole to know where to drill. But when I'm drilling through the bushing, it MUST come out through the hole in the bottom!
So here's how I did it.
I removed the old bushing from the elevator. Then I clamped a foot long 2"x4" to the top of the elevator. Using a 18" long drill bit, I went (from the bottom) through the existing holes in the elevator and drilled through the 2"x4". Then I inserted the new bushing and drilled from the top letting the 2"x4" guide the drill exactly through the existing top hole of the elevator, drilling a hole in the new bushing and then out the existing hole in the bottom of the elevator.
Once that was done, I could finish up the canard tips. I put a 1 BID layup around the outside seam and all around the inside "pocket". When that cured, I sanded it down and mixed up some filler to fair it in.
October is turning out to be worse than September. Not as much travel, but a definite roadblock in the building process.
I've got a 40 year-old International Cub Cadet tractor that has a mowing deck. I got this tractor about 7 years ago for free from a friend that didn't need it and it's like the energizer bunny. It just keeps going and going. After I had it about a year, I found a plow blade for it so in the winter I use it to plow the driveway.
Well I started cutting the grass and the engine started making a bunch of noise and then stopped. I called a couple shops and they said anywhere from $800 to $1,800 to fix.
So I dragged it in the shop and started pulling the engine apart. I found the connecting rod in about 8 pieces in the oil pan. So October is "rebuild a Kohler K301 engine" month.
I was on track to finish the rebuild on 10/22 when I discovered that I was shipped the wrong piston. By the time I get the correct piston, I'll be in the middle of a two-week training trip. But I'm hoping to be building again by the 12th of November.
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