dang elevator

[SeanB]

Recently drilled the bearing hole for the elevator horns on my RV7. Used the correct drill bushing, then step drill to get the final 0.25" hole. Individually, the bolt slips thru the bearing, then the hole in the horn if done from the inboard side. Put both elevators on, then there is a problem. Hole alignment is fine, but the head of the bolt, and the nut make contact on the tubes of each horn. The holes are too close to the tubes and cause interference.

I checked numerous times before drilling these holes that to center of rod bearing is 13/16" from web, and that the gap between the counterbalance arms and HS are a symmetrical and constant. I've now gone to the welder and had 4130 erase the holes.

The plans state Max 7/8" for rod bearing measurement. That's only 1/16" more than where I already tried. Not sure that will be enough to provide hardware clearance.

I also notice the newer plans have an extra aft doubler at the rod bearing locations. It appears these measurements are being taken from that surface, not the spar web. I don't have those doublers installed (SB 14-02-05) so I'm wondering if I add the thickness of the doubler to my allowed gap.

Anyone else run into this problem?
Any suggestions?

Thank you!!!

[wirejock]

Sean
My bearings were adjusted when the tail feathers were mounted and drilled. I used a long section of polished steel rod inserted through the bearings then measured using a caliper. All were set to 7/8". If they are not equal, it's quite possible the horns could be out of position enough for the hole to fall close to the horn shaft. Clamp the elevators in trail then drill. My holes are clear enough for hardware. About 3/8" from the shaft.
By the way, I manage a Google Group of builders in Colorado.
If you would like to join, shoot me an e-mail from a Google account.

[SeanB]

Larry,
Thanks. I like the rod idea. I'll give that a try. Will send a Google address. Already know a bunch of CO RVers, and looking forward to meeting more.