Once the transverse 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 (not happy with this type of progress). 

Waiting for Steve to get the wrench on the inside nut.