Smaller Rivet for Empennage Tips?

[mlwynn]

Hi all,

I am about to rivet on my HS tips. The pre-punched holes are 3/32. The plans specify CS4-4 rivets. I would rather use a 3/32 rivet. It willl match the other rivets better. I also hate how big and generally ugly the CS 4-4 rivet head it is. I looked is the ACS catalog and couldn't figure out what might be the correct aluminum 3/32 rivet. Any suggestions? Anyone else substituted for this?

Regards,

Michael Wynn
RV 8 Finishing
San Ramon, CA

[DanH]

Hanson Rivet

http://www.hansonrivet.com/w14.htm

PASK302 or PASK304

[Andy Hill]

If you finish your Emp tips off nicely... you won't see the CS4-4s



Andy
RV-8 G-HILZ

[mlwynn]

Thanks for the reference, Dan. They had just what I was looking for.

Nice job, Andy. I have been doing that on the elevator side. It doesn't look like you had any trouble with the aluminum/fiberglass interface. I used 1.75 oz cloth in two layers to go from the tips over the fiberglass, about 1" overlap. I keep wondering how well it will bond and how the finish look will be. What cloth did you use? Aluminum prep?

Usually they say to acid etch the aluminum before you paint. I didn't do that before I laid up the fiberglass and wonder if it is kosher to do so now. I was thinking to give it a good scotchbriting and then apply the primer. I wanted to prime over all the fiberglass before it has a chance to be exposed to oil and/or the elements.

I extensively studied these at Oshkosh last year. Some people finish the tips and rivet them on. You can see the rivet line and it looks good. Others have done it your way. Also looks good. I was half thinking of using your style on the elevator and visible rivet line on the HS. Don't know how that would look.

Thoughts?

Michael Wynn
RV 8 Finishing
San Ramon, CA

[Andy Hill]

Scuff the AL side, and as you say, acid etch.

1 layer of glass (no idea what weight - sorry!), maybe 1.5" wide (?) covering the join, then covered in peel ply. I think I used resin, glass, then further wetted the glass with resin + lightweight sandable filler additive, then the peel ply to aid sanding / minimising weight.

Sand off and some more filler used. Looked good-OK. The painters (v good - Airtime at Bournemouth UK) made it really work with extra filling and skill - if you look closely you will see rivets have "disappeared" in filler some distance from the tips.

We also used that technique for the wingtips. Nearly 300hrs / 550 flights and lots of aeros and no cracking (yet ).

The technique above was passed to me by someone else in the UK... so not claiming any real credit apart from showing it working in action.

<<Thoughts?>> I'm biased but would say blend all the tips in - not only do we love it, but also those who see it

Andy