After I installed aluminum "booties" on the gear leg ends last year, I had a hard to diagnose problem with the pilot side brake. It would work on the ground, but on landing, the left brake was weak no matter how many times I bled the brakes. My new mechanic finally diagnosed the problem. The gear door fit had changed and now impeded the travel of the brake cylinder.
My fix was a lazy one since it was the flying season - I just took off both gear doors. The problem is that it interrupted my paint scheme. It is supposed to look like the top picture but a bunch of otherwise nice photos of the plane at airshows were spoiled by the missing doors, as seen in the lower picture.
The fix is to cut up the parts of the door that don't fit and to re-contour them to fit the new gear leg ends. This is a quick documentation of the fix, which I finally got around to. I couldn't take the plane to Oshkosh next month without restoring it to perfect showplane condition.
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The first step was to cut off the part that didn't fit. I used a Dremel with a cutoff wheel. You get to be an expert with this tool if you build a fiberglass kitplane.
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| Lines marked with Sharpie and ready to cut with Dremel |
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| The Dremel makes a nice smooth cut. |
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| The cut up gear door. |
Next up, I prepare the gear door surface to accept new fiberglass layups. I use a random orbit sander to remove 1 1/2 " of paint and filler.
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| Ready for new glass. |
I put the plane on my homemade jacks, retract the gear and install what's left of the gear door.
Next, I make forms out of tagboard and duct tape to get a perfect transition to the lower strake surface from the edges of the door. Fiberglass is then laid up on the clean glass on the door and then onto the duct tape. Epoxy doesn't bond to duct tape, so it is used for flanges and transitions like this.
After cure, the door is popped loose and the tagboard and duct tape are removed, leaving a rough layup that matches the hole.
Next, the new fiberglass is trimmed, filed and sanded to fit perfectly.
Two more plies of glass are then laid up on the opposite side for strength.
Once trimmed, I installed the new door and flight tested it. It worked great.
Next up, I use filler to get the new portions nice and smooth.
After sanding, the door gets sprayed with filler/primer and wet sanded with 400 grit.
It is now ready for a quick trip to the paint shop. Only the white part will be re-sprayed without getting into the complicated trim colors.
....and here it is, the door back from the paint shop today, good as new and ready to reinstall. This is one of the reasons why I love fiberglass.
Still lots of cosmetics and touch ups to do before Oshkosh. Only 36 days until we leave for the show! We will be parked over by the Warbirds. Try to guess which door was redone if you stop by.
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