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DWest wrote:I can’t see how nut plates would work in fiberglass. Sonex told me the same about the tail tips, factory only so I did and had only one slightly crack the fiberglass. That was because it was too tight in that area to begin with.

Guess the aluminum rivets will be the solution for me too. Got a part number?

Nutplates work fine in fiberglass. My tail tips have nutplates.

I used aluminum 1/8" avex rivets.
https://www.aircraftspruce.com/catalog/ ... kkey=11312

I have put nut plates in fiberglass plenty of places. I usually soak the edges with thin CA before riveting but its probably overkill. I don't think it really penetrates properly cured fiberglass, but it gives me a warm feeling ;)

The aluminum rivets I used when riveting into fiberglass are the from a Zenith kit and I think were listed as Avtech A4 (1/8") rivets. The Avex rivets look like they may be similar. They are identified by a small groove around the stem that creates a weak area where bulging first starts, then the bulge is pulled down onto the fiberglass clamping it to the aluminum. If you pull a standard Sonex rivet into fiberglass it bulges outward inside the fiberglass and tends to breakout if near the edge. Try this with some scrap material. The Sonex SS rivets are much better when fastening two pieces of aluminum together as the expansion eliminates and lateral movement between the parts. Zenith uses (or used to use) Avtech or an equivalent rivet and I made a test Tee square with just a couple of rivets at the joint, this movement is very evident with these rivets. I also used the aluminum Zenith type rivets rivets when fastening aluminum piano hinges to fiberglass even though the head of the rivet is on the fiberglass the SS rivets tend to distort the piano hinges in this application. Just be sure your aluminum rivets have the groove and that they first form a bulge when pulled and then pull that bulge back onto the materiel clamping it, test on some scrap if in doubt.

12 years in service so far, no sign of any problems with those rivets.

David A.

Funny this post came up I have literally been contemplating the same with my wingtips, I put all the electrical connections in the landing light location so a quick disconnect is available if I needed it without removing the wing tips, but the more i think about it the more i want to mount them with nutplates and screws for easier access to both the wiring behind the lights and the landing/taxi light,

That being said my light mounts have nut plates works fine in fiberglass so no concern there keep your edge spacing reasonable and you will be ok. also you have some access to the cabling if you remove the aileron as there is an inspection hole in the last bay so technically riveting is still an option if you did the wiring like i did. as the conduit will get it to the back bay and you can use a long gripper to snake the cables if you really needed to replace that set of cables.

Details in my build log if anyone is interested in my wiring.

Thanks all. I’m going to go with the aluminum rivets from aircraft spruce. Not even close to starting the fuselage yet and im getting excited to have this thing flying. I figure I can do mods later on. Unless it’s something that is really going to make life and maintenance easier.

Should I use the.187 grip rivets?