What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Horizontal Stabilizer attach brackets

huse0054

Well Known Member
Getting ready to rivet the Horizontal stabilizer together today. The attach brackets are already riveted to the spar. Out of curiosity I placed the front spar with attach brackets on a flat cast iron table saw top and measured the distance from the ends of the table saw top up to the bottom of the spar to see how symmetrical the measurements are. Over a distance of 5.5' I am 3/16ths lower on one side. I figure over the entire horizontal stabilizer length it would be closer to 1/2-3/4" lower.

So my concern is the discrepancy is due to a wandering drill bit that caused one of the attach bracket alignment holes to be slightly higher than what was called for. Or it could also be that the spar itself has a bow or sag and will be corrected when everything else is riveted together....

Would you?

1. Build on and adjust for it later on down the road. (not sure how)
2. Drill out the attach brackets, remake them and hope the new ones align better
 
The previous builder of my RV-9A partially complete project really buggered up the location of the HS mounting tabs. It looked odd attached to I verified with a digital lever that when it was mounted, it was 3 degrees off from being level. I ended up having to drill off the mounting tabs, then fabricate new ones and drill and rivet so the HS was level.
 
Used a digital level to check the table saw top and the HS spar and they are both level to each other when the HS sits flat on the cast iron top. I feel better about that and will proceed on. I suppose if I need to remake those brackets in the future I can but they look good and visually I can't tell a difference between the two.

Not sure why I am getting different measurements with ruler.

I also checked the distance from the bottom of the HS mounting brackets to the spar with a digital caliper and one of the brackets sits 10 thousands lower. I think that is acceptable.
 
Back
Top