dbaflyer

Well Known Member
I was fitting the right gear weldment for my rv9a. It did not want to sit flush against the center section and I think I see why. Has anyone else ran into this? I'm thinking this hole needs enlarged to 3/16 to accommodate the large rivet on the center section.

This is looking at the back of the right gear weldment.

GearWeldmentBadHole2.JPG


The blue tape indicates the hole that needs to be larger to accommodate the rivet on the center section. This photo shows the rivet that is interfering. It is just below the nut plate.

GearWeldmentBadHole4.JPG


You notice the holes to the left which have the doubler are enlarged on the doubler to accommodate the large rivets.

GearWeldmentBadHole3.JPG
 
After I posted that I quickly concluded that hole is not the problem. It is just like the other holes without the doubler so it has just as much clearance. Here is a picture of what the problem is.

There is about a 3/32 inch gap between the center section and weldment. The weldment does sit flush on the inboard most edge, but not on the outboard side where the main wing bolt holes are.

GearWeldmentNotFlush1.jpg
 
Check propperly!

Hello

I ran into the same on my RV-7A. One rivet I put in the wrong way around. Check the drawings, where they show the F-7101-L/R Gear Attach Web. Look for the lowest rive that the web/center section, this one should be installed flush on the inside.

Then I countersunk all the hole that sould give the rivet head space, on my parts, the position of the hole where off by a small amount. By looking close we found a missing hole that gives way for the rivet head. I informed Vans but they did not react. A buddy found the same a year later. it is on your first image, on the right side, the 2nd row of rivet-hole, the steel is cut at an angle, but it does not pass the rivet fully. We needet to file a half circle.

Do not forget the washer under one screw hole! There is one screw that goes throu the gearleg weldment into the spar, but on a position, where the doubler on the spar is shorter.

Regards, Dominik
 
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When I fit my gear leg weldments, I did them laid out on the center section prior to having anything else riveted together. The weldment wouldn't lay flat. Some of the rivets on the spar carry though section and the relief holes in the weldment were not lined up well enough. I ended up having to file off some of the back part of the relief holes just a bit to allow clearance for the rivet heads. It was just a tiny bit -- probably a mm or so, but just enough to let the weldment lay flat on the center spar carry through section. You also need to make sure that the powder coating in the wing spar bolt holes can accommodate the spar bolts. Mine were a bit tight.

There is one place on the spar carry through that requires a single washer be put behind the weldment to take up the space where the surface isn't flush with the weldment (lower bolt hole left of the gear tube in the photo - check the plans). I also had to trim a bit of the aft edge of the floor stiffener to get the weldment to fit behind it. Another hint, do not predrill the hole in the bottom skin for the blue brake line fitting. Mine didn't perfectly line up with the weldment.

1106777685_9FjHb-M.jpg
 
Tried a couple things to help the fit a little. I was pushing the gear tube a bit too far through the skin hole. After pulling it up slightly the weldment went a bit closer to the center section. After using a mirror and not seeing any rivets in the way, I tried bolting it on once. It snugged right up with very little tightening of the bolts so I believe there isn't anything catching it anymore.