D

dsm8

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I am considering screwing the fiberglass tips to the empenage intead of riveting. Does anyone know what size nutplates and screws I should use.

Thanks

Don
 
consider carefully...

other than future modification of the vertical stabilizer cap for a camera it is hard to imagine any benefit to making the tips removable... consider carefully just what you expect to gain. if you ever need access (unlikely) it is easy enough to drill out the pull rivets.
 
I considered using screws and nutplates as well, but when it came time to fit them, the rough fit was pretty bad...... nothing that could not be fixed with some lightweight glass and microballoons, but it wouldn't have looked pretty if I just screwed them on.
 
I put my VOR/GS/LOC Comant antenna under my VS tip and wanted it removable for future service. I put four #6 nutplates on each side with countersink in the glass and #6 dimples in the skin for the screws. Pretty much the same as for the wing tips. I replaced all the Vans supplied #6 phillips screws with 100* Torx drive SS screws http://www.microfasteners.com/catalog/products/SSCFCMXS.cfm . They are the "Bees Knees" for EZ removal!;)
 
My elevator tips looked pretty bad too so I taped the seams and glassed them over. Looks much better and gave me some practice with fiberglass that I have never worked with before.
DSCN2599_000.jpg

DSCN2607.jpg
 
Don,
All the fiberglass tips on my aircraft are removable and I used the hardware Vans specifies as an option to the pop rivets for the wing tips; AN507-6R6 screws and K1000-06 platenuts. I substituted stainless steel screws for the standard cad plated ones as they look better. My understanding is that the SS screws can produce corrosion on the aluminum but most likely only an issue in very humid environments and with an unpainted aircraft. I have not found this to be an issue.
Removable tips can easily be repaired if they are damaged pushing the aircraft around the hangar. I have had a number of RV builders that pop riveted or glassed their tips on and after seeing mine, admitted that the screws (especially SS) look better and compared to glassing on the tips, the screws help make the RV look like a real metal aircraft rather than a slick glass lookalike. YMMV.

Fin
9A
 
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Don,

Making the empennage tips removable with screws and nutplates is an option that pleases my eye. No doubt it is an option most builders see no real use for and that is their choice. I have removed the tips on more than one occasion and am very glad screws facilitate the process. At one time I removed them so they could be painted. I routinely remove the empennage tips when I polish the airframe and anyone with a polished airplane knows exactly what I am talking about. Polished airplane or not, some people claim you can simply drill out pop rivets if you have to. Sure enough you can do that but what they don't tell you is that process invites producing oversize holes that you will then have to deal with or ignore. Besides, pop rivets and the look they impart simply do not convey much of a substantial or "military" appearance to me. Heck, even Cessna screws the tips on.

You can use whatever size screws and nutplates you choose to use. For the most part, I used #6. My thinking was that the Phillips head on #4 screws tend to be easily rounded out and #8 screws and dimples seemed a little too big, standing out a bit too much for my taste. For me, choosing #6 screws was nothing more than an arbitrary decision in keeping with my own "vision" and perception of a balance that falls somewhere between practicality and a cosmetically pleasing look.

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Photo please?

Hello Rick,

I always find your contributions valuable. Thank you.

Any chance that you can show and tell how you fixed the 'platenuts' to the tips please?

Regards

David Richard
 
Levrie said:
......Any chance that you can show and tell how you fixed the 'platenuts' to the tips please?....David Richard
Click to expand...
David Richard,

There is not that much to show. The nutplates are typically attached to the empennage tips with NAS1097 rivets. Some builders do use softer rivets in fiberglass and I did too in the wingtips using the #4 wingtip screw kit from Cleaveland, but I did not experience any problem using and setting 1097's in the empennage tips.

2unu2hl.jpg
 
I attached mine with #4 screws and nut plates, the same way Rick did.

I wasn't sure if a pop rivet would suck the tips up nicely to the skin, where a screw most definitely would. Also I figured it'd be easier to repair or replace should it ever get hangar rash. It also matched the VS where I definitely wanted it removable to add an antenna or camera or something.

It's done and the extra time didn't bother me. I'd probably make the same decision today, but no idea how it'll play out in the long run.
 
Looks nice. I don't see any locking element. Do you ever have any problem with them loosening? What would be the disadvantage of, say, MS21078-06 which is about the same but with an elastic insert?
 
delusional said:
Looks nice. I don't see any locking element. Do you ever have any problem with them loosening? What would be the disadvantage of, say, MS21078-06 which is about the same but with an elastic insert?
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most nutplates are stiff enough when threading there is very little chance they will loosen. these are taken off only very occasionally, I do not think you should thread them enough times to make the threads loose
 
put in nutplates

Thanks for the inspiration, Rick. I put in nutplates and I'm happy with the result. It wasn't real difficult, but, as everyone says, it adds to build time. I bet in the long run I'll get that time back, but perhaps not for many years.

It looks like you also chose the soft metal cap option for closing the hs tip fairing. Is that right? I did, too, though I must say, while it came out fine, it took me a lot longer than I would have hoped, though mainly due to doing it twice. I made the caps and attached them with rivets and proseal before realizing the fairings had to be trimmed to clear the elevator counterbalance. Just another "education and recreation" experience.
 
When looking at Ricks SS screws; are they set in dimples or machine countersunk? It appears to be ms based on nutplates used but not sure.
 
I'm at the same stage on my emp tips, they are fitted well but I was curious about finishing.
1. Should I put the 3 coat epoxy skin on the tips with them on or off the plane?2. Then should I leave the epoxy skin untouched or should I finish sand and coat with primer, I'm undecided on paint and it will be several years.
Thanks,
Andy
 
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