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Stabilizer Tips - the problems & the plan

ERushing

Well Known Member
Since my QB Wings & Fuse won't be here for at least another month, I've decided to finish the tail fiberglass.

My plan is to fill the edge/gap between the fiberglass tips and the aluminum skin with dry micro after roughing up both the skin and tips, lay a light piece of fiberglass tape over the gap (pre-wetted using the plastic sandwich method) and then microslurry over the top of that + sanding to fair. Since I have plenty of time and I like the way that finish looks, that's the plan.

I've run into a couple items that I want to address before heading down this path. My apologies for the poor photos.

Issue #1 - Difference in surface height between elevator tip and elevator skin leading edge. My plan to address this is to sand the gelcoat off, apply dry micro to level the gap, sand to shape. Anyone see any issue with that? Any advice?

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Issue #2 - This one's the more concerning of the two. There's a significant difference in the width of the hs tip vs the elevator tip. I'm a bit more perplexed as to how to fix this one. One option would be to stuff an oversized piece of foam shaped to match the elevator into the hs tip. Maybe add a bit of heat to soften the piece. Another option would be to add a bunch of micro on the elevator tip and match the outline. That would be a lot of micro... Has anyone else seen this? Any recommendations? (I know... horrible picture.)

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Since I'll be sanding some of the gelcoat off, should I just sand it all off?

Thanks!!
 
On problem #1: No problem with the approach you suggest.

On problem #2: Since you're planning to fair the gap, if you have acceptable edge distance, why not just slide the HS tip slightly outboard to match the elevator tip, then drill and rivet it in that location? The filler and fiberglass will take care of the joggle.

Alternately, you could sand down the joggle ridge on the elevator tips, trim the inboard edges slightly, and they would nest more inboard than their "natural" location.

Only sand off all of the gelcoat if you're looking for pinhole practice. ;-)
 
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Thanks Kyle!
I already drilled the elevator tips and cut the inboard edge to fit. I suppose I could always fill the holes with flox and re-drill to batch the HS tip.
 
I did it the other way around. Actually, I found the flange on the HS tips was too wide, so I trimmed them down and then fit them. I still had a bit of the gap you are showing, so I then trimmed the joggle back just enough to git them to fit. Those tips are a rough fit anyway and after cutting them to match the counterbalances of the elevators and adding a foam rib and glass to close them off, that part had taken a significant bit of modification.
 
The only problem with sanding the gelcoat off of the fairings is that you could weaken the glass and cause it to track down the road.

P.S. What is Dry Micro?
 
Simply removing the gelcoat should not affect the strength of the part. There's no glass in gelcoat. It is simply colored resin added to the mold before adding the actual glass/resin layups. If you sand into the raw glass, you can simply seal with a coat of thinned resin. I do this with parts I will be using micro or flox on, as well, in case the micro or flox were too dry to achieve good adhesion.
 
This thread is well-timed for me, as I've finished my empennage, but my quickbuilt kits are at least 6+ months away. I'll be taking the same approach; learning the tricks of the fiberglass trade as well as exterior painting... that is if I can keep my shop warm enough this winter.
 
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