longranger

Well Known Member
Pardon me in advance if this thread doesn't belong in the general discussion forums. Since all RV's I'm familiar with have a similar setup on the aileron control system I thought it would be appropriate here.

Specifically, my question is about the VA-111 end fittings in the 1-1/8 dia. stick-to-bellcrank push tube. I'm building my W-716 (would be W-816 in an RV-8), and the VA-111 fittings seem awfully loose in the tube bore. They slide in very freely, and actually "rattle" around in the tube a bit; WAAAY looser than the end fitting the the smaller diameter steel tube between the bellcrank and aileron. I don't have a good way to accurately measure inside diameters, but by wrapping one VA-111 fitting with a full turn of 0.004 masking tape, it wouldn't go in the tube, but with a half-turn it was tighter than a bare fitting but still a bit loose. I'm guessing the VA-111 is about 0.005 to 0.006 smaller than the bore of the tube.

Is this normal?? I did a search and all I found was this thread over three years ago concerning VA-111's not fitting due to primer thickness. I'm wondering if Van's decreased the diameter of the VA-111 a bit to alleviate this issue? Considering the slightly loose fit, would it be appropriate to use a structural adhesive (like Hysol) in addition to the rivets to fill the gap?

Thanks in advance for any help here.
 
tube

I painted then inside of my tubing with some left over primer from another project and it made a good fit also I get alittle carried away and put some epoxy on the fittings and dip the rivits in epoxy before pulling them. Im sure thats over kill but a friend that works on rockets at Nasa said they done it on rocket pop rivits . Bob
 
Mine fit more freely than the aileron - bellcrank location too. However, they don't budge after I riveted them in place :D