R

rrd1_99

Active Member
I would try and post a pic, but I haven't done it yet and I just don't have time today to find an image sharing website to use. So if 1 picture=1000 words, then this will be a long post...;)

I have a QB fuse and am finishing my emp attach (drawing 27A). Today I match drilled the holes attaching the F-981 forward VS attach plate to the rear deck (F-714, 710C & 710B). These are the two 3/16" holes oriented vertically. After drilling the second one I reach in there to feel for burrs and instead find the shop head of a -3 rivet right next to the new hole. Sure enough, there's one near the first hole as well, but not as close.

The manufactured heads of the rivets are not visible and must be underneath the F714 deck. As best I can tell, these must be flush rivets countersunk into the top of the 710B or 710C, maybe "keeper" rivets used by the QB builders. I can't find them called out anywhere on the plans.

Wouldn't be a problem except for the proximity of the one rivet to the underside of the bolt hole. My plan for a fix is to notch a 960 washer to accomodate the rivet and use an extra washer between that and the nut.

Any input would be appreciated!

Roger Barnes
-9A slow QB
La Grande Oregon
 
Fix

I think your idea may be a plausible one. Another idea is to remove the shop head of the rivet if indeed it is a keeper rivet and that you can do so without harming the stringer or other surfaces nearby.

Maybe Mel or other DARs can jump in on this.
 
Considered that...

I thought about removing the shop head with the SB wheel on a die grinder, but it would necessitate crawling all the way back into the tailcone and I would be concerned about getting it smoothed down flush without affecting the surface of the angle.

I'm still a bit stymied by the presence of both these rivets, as it seems strange they would go to the trouble to countersink them to allow the deck to sit flush if they are just "keeper" rivets.

Any other QB'ers out there notice having these mystery rivets?

Roger Barnes
-9A slow QB
La Grande Oregon
 
Fix

Sometimes it is hard to get a reply on the weekend.:confused: Maybe Mel or one of the other Guru's will see this Mon. and offer a better solution.
 
Just bumping to top..

Now that the big weekend is over, anyone have any ideas or input on this one?

Any help is much appreciated!

Roger Barnes
-9A slow QB
La Grande Oregon
 
It's hard to give a recommendation without actually seeing the rivet in question. If I'm understanding correctly, the parts being held together by the rivet will be "sandwiched" by the bolt/nut combination. If that is indeed the case, I would remove the shop head with a dremel cut-off wheel so that the washer will lay flat on the surface. I would not use an addition "modified" washer as that will reduce the surface area and load factor.
 
I think in an ideal world, the bolt hole would have been drilled in exactly the same location as the original rivet, thus that rivet would have been sacrificial. That said, I have the same problem and have been putting off fixing it. I will probably end up grinding off the shop head (quite difficult to get at this easily) with a combination of dremel and hand files, and then just using a normal washer.

greg
 
Been there; ground that ...

I found exactly that situation on my QB a few weeks ago. The two rivets were not perfectly aligned with the bolt holes (to allow drilling out) and they would be too close to the bolts' bottom nut and washer to ignore. So I had my Better Half hold a mirror in thru one of the lightening holes in the rear deck while reached in the other with a Dremel. Ground the shop heads off via the reflection in the mirror, and all is well now. I also discovered I could never be a dentist ... working backa**wards thru a small mirror is AWFUL. :eek:
 
I don't know of these two rivets: I haven't drilled the two holes in the VS plate, yet.

What I can say about empennage attach in a 9A QB is that builder shall also build elevator stops: down and up. While the latter had no problems (one should only be aware of drilling it clamping the sole aft part of VS; in such way, I suppose both horns will touch the angle at the same moment), the first seem to attach in the same place where a certain number of AN470 AD4 rivets (4, if I recall) already are set. I was thinking of removing them, after looking again at DWG27A. Anyone experienced such problem?

Camillo
 
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