RV-7A Gear Leg Mount

macrafic · #1 06-28-2009, 12:22 PM

I'm wondering about the order of things when it comes to the gear leg mount on my 7A. It appears as though I have to rivet on the front side skins first, since there are rivets that would be impossible to buck if the gear leg mounts were already installed. However, this also implies that the front bottom skin would also have to be riveted, since there is at least one side skin rivet that goes through the bottom skin and must be flush on the inside so that it does not interfere with the gear leg mount.

However, when I have both the side and bottom skins on, I can't figure out how to get the gear leg mount installed. Between the need to fit the gear leg mount under the nutplates on the main spar, fitting the side support of the gear leg mount behind the F-902 bulkhead, and extending the mount through the bottom skin, I can't find the right combination.

The only way I can seem to assemble everything is side skin 1st, gear let mount second, and bottom skin last. However, as described above, There are rivets on the side skin that are impossible and others that are difficult to buck because of the gear leg mount being in the way.

Guys/gals, what is the trick that I'm missing here?

AltonD · #2 06-28-2009, 01:40 PM

Gear legs are last (after the floor and side skins). Thre is a hole you have to make in the floor skin for the gear leg to exit through.

I'll also give you a BIG tip. Buy Bonaco brake and fuel hoses. The aluminum tubing is a real pain on the A model. I did the aluminum, took two days and had to drop the gear legs. I just changed to the Bonaco. I should have invested in theses first.

kevinh · #3 06-28-2009, 03:47 PM

YMMV - It is worth giving the aluminum lines a shot. In my case I guess I was lucky - only about an hour to do both sides on my 7A.

macrafic · #4 06-28-2009, 05:05 PM

[quote=AltonD;337770]Gear legs are last (after the floor and side skins). Thre is a hole you have to make in the floor skin for the gear leg to exit through.

AltonD, I already have the hold in the bottom floor. That is my concern. I can fit it all together if I put the floor on last. But, for the reasons I stated, I can't do that. Is there a trick to getting the gear leg mounts in place after the side and bottom skins are on? To even get the mount over to the hole, it has to fit over/under/slide along so many other things, that I can't get it figured out.

I agree with your tip on the Bonaco; made that decision long ago! I have no doubt that I could go the aluminum route but, personal choice. Lots of RV's flying both ways.

chunt0 · #5 06-28-2009, 06:01 PM

One thing that will help is to remove the top three outboard platenuts from each side of the main spar. Reinstall them after the weldments are in their final position. If you knock the inboard top corners off the weldments, you will only need to remove the outboard two platenuts. Removing the platenuts should also make it unnecessary to doubleflush the outboard five floor to spar rivets.

allbee · #6 06-28-2009, 06:30 PM

Quote:

Originally Posted by kevinh

YMMV - It is worth giving the aluminum lines a shot. In my case I guess I was lucky - only about an hour to do both sides on my 7A.

I was lucky to I guess, it took me 15min each side, but I cheated, I went around the front leg, I guess you call it, and now that it's flying that bend around the front just before it goes out to the wing doesn't effect anything. I also have carpet there now and you don't see a thing.

The brake lines, I used the plastic lines, no leaks and was a breeze to bleed because you can see the air if you have it. If you do, you just remove the line right where the air is and let the hose drop down and the air comes right out.

Flying Scotsman · #7 06-28-2009, 11:45 PM

Yeah, removing those platenuts made installing the gear weldments pretty straightforward...woulda been a booger otherwise. We only had to drill out the outboard two platenuts, YMMV, but definitely take 'em out and things will go much easier.

AltonD · #8 06-29-2009, 01:07 PM

Quote:

Originally Posted by chunt0

One thing that will help is to remove the top three outboard platenuts from each side of the main spar. Reinstall them after the weldments are in their final position. If you knock the inboard top corners off the weldments, you will only need to remove the outboard two platenuts. Removing the platenuts should also make it unnecessary to doubleflush the outboard five floor to spar rivets.

I forgot all about this. I also remove the three platenuts. Actually, I am not sure I will even reinstall them.

macrafic · #9 06-29-2009, 02:34 PM

Thanks guys! I'm sure that will do it. Now, I have to do home and find out what those nut plates for for in the 1st place!!!!!!

allbee · #10 06-29-2009, 03:00 PM

something else that might help. I didn't run the al. tubing for the brakes through the center. I came off the firewall, park brake(love that device) and than went left down the side wall to the fitting to the gear wheels. Off the firewall, park brake across the front down the right side wall to the right landing gear wheel. Carpet covers that also.