Blending fiberglass and aluminum

[Blain]

Finishing emp and fiberglass tips. I've seen ships where the builder blends the tip into the skin and then hides the first 3 rows of rivets. In this case the Horizontal stab and counterweight. I'm not exactly proud of that area but I don't think its wise to cover rivets with filler or expect the 'glass/aluminum line to not crack out at some time.

Not building a show plane but I do want it to look nice.

Can't find any info on filling the heads of the blind rivets. I do expect to flatten those out.



Opinions?
Blain

[rvbuilder2002]

Mine opinion is that a metal airplane is a metal airplane.
Hiding rivets doesn't change that. It will usually instead raise questions regarding what the builder is hiding. In the context of judging for workmanship awards it is generally a negative

I do fill the stem holes on blind rivets. There are also tricks you can use to minimize (not hide) the transition between a fiberglass fairing and the skins it attaches to, but it is best done before the F.G. part is riveted on.

[Blain]

Originally Posted by rvbuilder2002

Mine opinion is that a metal airplane is a metal airplane.
Hiding rivets doesn't change that. It will usually instead raise questions regarding what the builder is hiding. In the context of judging for workmanship awards it is generally a negative

I do fill the stem holes on blind rivets. There are also tricks you can use to minimize (not hide) the transition between a fiberglass fairing and the skins it attaches to, but it is best done before the F.G. part is riveted on.

What do you use to fill the stem holes? And how do you sand/smooth it out?

Blain

[EdH]

Nice job on the tip fitting - If that was mine, I'd be proud of the work and not do any filling.

[Mike S]

Blain, you are doing some nice work there, keep it up and all will be fine.

I am opposed to filling the rivets, makes it a lot harder if you ever need to remove the fiberglass tip.

As to the rudder bottom, I would suggest you mount it with nut plates-----these get damaged easily, and it makes running the tail lighting wires much easier.

[Andy Hill]

Finishing emp and fiberglass tips. I've seen ships where the builder blends the tip into the skin and then hides the first 3 rows of rivets. In this case the Horizontal stab and counterweight. I'm not exactly proud of that area but I don't think its wise to cover rivets with filler or expect the 'glass/aluminum line to not crack out at some time.

I think there are 2 considerations here:

1. The "Glass/Al line"
2. The Rivets

Filling rivets in principle is a strange idea as detailed above - after all, where would you stop on the whole RV?

However, removing the Glass/Al line some people do undertake - personal choice. We did it - including on the wingtips - and it looks great and is not a great deal of work. The main disadvantage as above is you cannot so easily remove the offending part.

As you point out, the issue is the line then cracking again. The solution is to scuff / etch the AL, and then glass one tape layer across the gap - then cover that layer with peel ply and roll smooth. When it's cured peel ply off and all you've got left is some typical filling / sanding. As a consequence of the glass and fill process, yes, some rivets will get filled, but that is a secondary effect, not the aim.

A (not v good) photo:

[Blain]

When I questioned filing the rivets I was referring to the blind rivets. I do want to flatten the head but not sure what technique to use. I'm thinking a small syringe? With epoxy or body filler? It needs to be a delicate application.

I'm sure someone has invented this wheel before

[rv7charlie]

One technique with regular driven rivets is to wipe 'proseal' across the head with a finger (you still see the rivet, but it fills the tiny circular 'valley' between the head & the flat surface of the skin). Would that meet your criteria of 'delicate'?

Charlie

[Blain]

Originally Posted by rv7charlie

One technique with regular driven rivets is to wipe 'proseal' across the head with a finger (you still see the rivet, but it fills the tiny circular 'valley' between the head & the flat surface of the skin). Would that meet your criteria of 'delicate'?

Charlie

What I was shooting for is a blind rivet head that resembles a driven rivet. Flat top. Without filing in the dimple. Just fill the mandrel hole.