Warped hinge assembly

when i squeezed the countersunk rivits at the tip of the bracket [where the bearing is] the bracket that has the shop head squeezed into the countersink warped away from the assembly. enough that it is unusable. what happened? everything was tight up until these 2 rivits were squeezed. can the pieces be drilled out and reused? the bracket warped about 1/32''. if i reuse can it be bent back flat? how do you prevent this?
didn't see this coming.

Bob,

Drill out the rivets and give a try at straightening the brackets. Long as there are no cracks and your rivet holes are still the original size, you should be OK. If in doubt, give a call to Van's support.

Some have suggested bending the tips of the two outside brackets (up by the bearing) inward slightly prior to assembly to keep them from bending outwards when riveted. Also make sure that the center bracket piece is perfectly straight. Mine were bent slightly and had to be straightened prior to assembly.

Other hints mentioned in the past have been to rivet in a random pattern, don't over squeeze the rivets, make sure the bearing relief on the brackets is perfectly clean (no primer) and that the reliefs are actually deep enough so that the bearing is not pressing outward.

Along with what I have mentioned above, there are some other causes/solutions mentioned in previous postings. Try a search on "flaperon hinge bracket assembly" or something similar.

Alex

Oh, I forgot to mention that some have suggested using an426ad4-5.5 rivets instead of the -6's in those two locations. These are not supplied and somewhat difficult to find. You can always cut or shave the -6's if necessary. I personally used the shorter rivets to avoid having to over-squeeze the rivets to get them flush. In the end, mine turned out OK.

alexe said:

make sure that the center bracket piece is perfectly straight. Mine were bent slightly and had to be straightened prior to assembly.

Click to expand...

This is not at all uncommon for thicker pieces, the way they are made by punching/sheering induces the curvature.

Good idea to develop the habit of checking for straight/flatness when you do the edge deburring.

thanks for the tips. the pieces were all dead nuts flat when i started. i think it has boiled down to squeezing the rivits too hard and the rivit is a bit longer than ideal. i did notice the gap open as i was squeezing the life out on one rivit. i will trim the rivits a bit , overbend the pieces slightly, rivit this end first and bot squeeze so hard.
an afterthought ...as the shop head is crushing and filling the countersink it seems that it would be ok to file any sticking out, as long as the countersink is deep enough.

Are you using a cleco in each of the holes, except for the ones you put the rivet into-----------asked another way, are you riveting the parts with any holes not already riveted or clecoed??

no, every other hole clecoed or rivited. and the tip was clamped with a spring clamp even though it was tight when i started.

When I had this problem I used a couple of very small C clamps to hold the two pieces tightly together. Clamp as close as possible to the rivet, leaving just enough room to get the squeezer jaws in place. I also seem to member ordering new parts at least once, after my first attempt at this step.

Yep, Bob, you're in the club now. I've got my original set of flaperon brackets in the back of a drawer with the other "extra" parts. All good advice above. The only thing I can add to the fray is that the rivets don't absolutely have to end up completely flush to the bracket surface. They can protrude slightly if that's what it takes to prevent distortion of the brackets.

sooooooooo to end this thread i was able to remove all the rivits. i first drilled with a #40 and then the head with w #30. then i popped the factory heads off by putting in the end of a #30 drill bit and ''tipping'' the bit . heads broke right off. flush are a little trickier and you need to drill a touch deeper than you think you need. too shallow and the drill end will pop out of the hole ''wallowing'' it. anyway, rivits all out with no damage. drill press ran every #40 hole in the center of every rivet shaft.
i bent the hinge piece slightly so in the middle of the piece it bowed out.
only the hinge piece that had the shop end of the flush rivets was warped.
i firmly believe i squeezed too hard on the first ones, causing the bow. this time when i squeezed the flush rivits i went more carefully. when the pieces spread a millionth of an inch at the tip i stopped!. new hinge brackets are perfect. thanks for all the advice. it's not the money but it felt good to redo the piece and not just pop for new ones.

Great news Bob!
Alex

Bearing Assembly Warp

I just tried my second attempt at this. Feeling frustrated. Ordered new parts after last attempt, Insured straightness, followed instructions and recommendations but hinges still opened up about .5 mm at end of bearing assembly. Are shorter rivets the answer here?

Rick,
Several posts in the past have indicated that the called out rivets might be a bit long for the two countersunk holes in question. You might try some 5.5's for those two flush rivets. If you can't find them anywhere, shave down a couple of 6's to the right lenght. Also, don't over-squeeze (see Bob's last post earlier in this thread on how he was able to lick the issue). Let us know how it goes.
Alex

Pre-bow

Like several others with early kits, on my first brackets the recessed surfaces that the bearings fit into were not machined quite deep enough, so the things bowed and the bearings got bound up pretty severely.

On the replacement set, I still had to relieve them a little with sandpaper, and also "pre-bent" the brackets just a little so that they stayed closed after riveting. Ended up using a file to shave off a bit of the shop head. Turned out well after a bunch of attention to a seemingly simple part. Still, a very useful experience. There are many more to come!

Hang in there!

Dave

I did mine today and they came out fine on the first try. I was especially careful to make sure the bearing were properly seated. I also used cleo clamps at the tips to help hold everything tight.

I put cleos in all the holes and then riveted them in a pattern that I thought would minimize bending.

I used the -6 rivets which did leave a little bit of a shop head above the surface. I hit the heads with a blue Scotch brite disk on a die grinder to make the surface completely flush

i think the trick to all this is not too much pressure squeezing the flush rivets. they are a little too long but as long as they fill the hole made by the countersink they can be filed. originally after my rivets were set the metal was tight but when i squeezed harder to get the rivits flush the gap appeared.
you can clamp tightly, cleco etc. but too much squeezing pressure ''springs '' [puts a bend at the rivit holes] the metal and the ends are going to open up after the clamps are removed.
avery tools gave me a good tip for shortening rivits....... find snug washers, nuts to slip over the rivit shank for the right length. then file, beltsand, whatever and the length always comes out exact and square.