[Pmerems]

Gents,

I am installing the main gear mount weldments in my RV-7A. I noticed in the instructions that it mentions that you can enlarge the wing attach bolt holes in the weldment a bit if needed.

I haven't enlarged mine yet (don't know if I need to) however I have a sinking feeling that I will need to. The reason I believe this is because the weldments aren't punched with the accuracy of the aluminum parts. The holes are over-sized but not by much. With all the non-close tolerance bolts in and tightened down I can't get a .435 gauge pin through one of the two top holes in the wildment/centersection. Since the bottom two .437 holes are inaccessible from the front, I don't know if I can get the gauge pin in.

So my question to those who installed the close tolerance bolts, did you need to enlarge the weldment holes?
Any input would be greatly appreciated.

 

[Norman CYYJ]

I have never had to make the weldment holes larger but they do have to be driven in from the aft side of the spar just enough to get the nut on. If you drive them too far thru you will have a duce of a time pulling them back to get the nut started. Have fun. Its murder on the back.

 

[LifeofReiley]

Most of the time you're just removing the powder coating in the holes. It's hard for them to get this accurate in the process.