Jim Ellis
Well Known Member
I always thought that the main landing gear mounts in front of the spar on my RV-9A had an unfinished look to them. As I was looking at the RV-7A that I am now building, I wondered if I couldn't come up with some kind of a cover for them. Since I have the -9A flying there is no urgency to complete the -7A so taking on a new and time consuming project is an interesting challenge.
Here's what the gear mounts on -7A and the -9A look like before.
And here's what they look like with the covers I fabricated.
I went through six sets of paper patterns before I got the close fit I wanted.
Using the final patterns I was able to create a full size fabrication drawing that looks like this.
The covers are made from a sheet of .025 aluminum that I had lying around. If you don't have a big scrap pile like I do (and after two planes I have a big scrap pile) you can order a sheet of .025 aluminum from Van's that will make both covers. On Van's "List" the part number is F-430, AS3-025 X 18 1/2 X 29 1/4, for around $25.00.
I laid out the parts on the sheet aluminum, drilled some 1/4" bend relief holes and zipped them out on the band saw. The parts for both the left and right covers are identical. The only difference is the direction that you bend the flanges.
Six bends are needed to form each box and these were easily done with a small bending brake.
I used a protractor and seaming pliers to fine tune the bends as needed. The parts are fastened together with AN426AD3-3.5 rivets spaced about an inch apart. Most of the rivets can be back riveted. Figuring out the riveting sequence of the parts is really the only tricky step in doing this. From the pictures you will see that flanges on the cap piece (Drawing Part C) are positioned on the outside of the cover.
To attach the completed covers I made four angled 9/16" wide tabs from .032 aluminum. These are riveted on the top of the covers and fastened to the spar cover with four 1/2" x 8-32 truss head screws and nutplates.
The covers weigh 7 ounces each before painting for a combined total weight of less than a pound.
I am very pleased with the results. With a little paint work these covers are going to look terrific and, because of the way they are angled, not a bad place to rest your leg. If you really want to get fancy you could cover them with a little carpet, fabric, or leather.
Now if I could just figure out how to install a cup holder in them that would be great!
__________________
P.S.
If you would like to make these covers for yourself see Post #8 in this thread for a full size drawing that can be used as templates for the parts.
Here's what the gear mounts on -7A and the -9A look like before.
And here's what they look like with the covers I fabricated.
I went through six sets of paper patterns before I got the close fit I wanted.
Using the final patterns I was able to create a full size fabrication drawing that looks like this.
The covers are made from a sheet of .025 aluminum that I had lying around. If you don't have a big scrap pile like I do (and after two planes I have a big scrap pile) you can order a sheet of .025 aluminum from Van's that will make both covers. On Van's "List" the part number is F-430, AS3-025 X 18 1/2 X 29 1/4, for around $25.00.
I laid out the parts on the sheet aluminum, drilled some 1/4" bend relief holes and zipped them out on the band saw. The parts for both the left and right covers are identical. The only difference is the direction that you bend the flanges.
Six bends are needed to form each box and these were easily done with a small bending brake.
I used a protractor and seaming pliers to fine tune the bends as needed. The parts are fastened together with AN426AD3-3.5 rivets spaced about an inch apart. Most of the rivets can be back riveted. Figuring out the riveting sequence of the parts is really the only tricky step in doing this. From the pictures you will see that flanges on the cap piece (Drawing Part C) are positioned on the outside of the cover.
To attach the completed covers I made four angled 9/16" wide tabs from .032 aluminum. These are riveted on the top of the covers and fastened to the spar cover with four 1/2" x 8-32 truss head screws and nutplates.
The covers weigh 7 ounces each before painting for a combined total weight of less than a pound.
I am very pleased with the results. With a little paint work these covers are going to look terrific and, because of the way they are angled, not a bad place to rest your leg. If you really want to get fancy you could cover them with a little carpet, fabric, or leather.
Now if I could just figure out how to install a cup holder in them that would be great!
__________________
P.S.
If you would like to make these covers for yourself see Post #8 in this thread for a full size drawing that can be used as templates for the parts.
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For someone wanting cup holders there are these: 
