Newbie question

[RVdreamin]

Guys...Got my empennage a couple months ago and have HS cleco'd and will match drill tonight. Couple of unrelated questions:

1. I have a pneumatic squeezer and have used it on the practice projects I think okay. As I begin to do it on the 'real thing' I started questioning myself about dimpling and the how to adjust the squeezer. On the practice project I closed the squeezer (push the button) and adjusted until the male/female dimple die touch then I backed it off about a half turn to allow for the thickness of the aluminum. The results seem to be pretty good....I mean the flush rivet is flush with the skin. Is my thinking okay on this or is there a better way to adjust?

2. Do not want to get in the primer debate, but I have decided to prime the interior. An EAA friend turned me on to some Rustoleum self etching primer that he said he has used and said it works great. He said to 'lightly' Scotch bright the surface to take the shine off the aluminum and spray the self-etching primer on. Any comments?

 

[bruceh]

Here is what has worked for me. I adjust the dies until they just touch, then use that setting on the skin to dimple. The yoke will give a bit to take up the thickness of the skin.

 

[RVdreamin]

Thanks Bruce....that makes sense to me...just looked at a Youtube video and they said the same thing.....Thanks.

 

[BobTurner]

Your dies should be leaving a witness mark - a circle about 3/8" diameter - on the metal. If they don't you need more force.

 

[60av8tor]

An EAA friend turned me on to some Rustoleum self etching primer that he said he has used and said it works great. He said to 'lightly' Scotch bright the surface to take the shine off the aluminum and spray the self-etching primer on. Any comments?

I haven?t started my build yet, so take this FWIW, but I am in the shop build, tool gather, read until my eyes bleed about primer, C-frame vs DRDT-2, etc phase. As I am going through this process I am slowly experimenting with various things ? drilling out rivets, etc. I had some rattle-can Rustoleum self etching primer that I had used previously on non-A/C projects and was always disappointed with its fragility ? thought it was my prep, or lack thereof. I experimented with this over the weekend. I had a scrap sheet that I taped into 3 sections: no prep, dish soap/scotchbrite pad, and dish soap/scotchbrite pad/acetone final cleaning. I then sprayed the sections with the Rustoleum and let it cure for just about 2-days. The good news is that it is quick, easy, and gives a nice smooth coat without any effort. The bad news is that I could remove all sections with a fingernail and some elbow grease. I can?t imagine using it while building and what it would look like as the build progressed. Perhaps something completely internal ? wing ribs ? but if I?m going to shoot a portion, I?m going to shoot everything. Just my take?

 

[RVdreamin]

Thanks everyone and Jon I think I will run some test like you did on some scrap aluminum. I was debating on the internal parts to prime everything, prime only where the aluminum joins (e.g. flange/skins), or no prime at all. I live realtively close to the coast so I decided to prime all internal parts which launches another debate about the best primers....jeepers.... decisions decisions

 

[bruceh]

I fully primed all of the interior surfaces with Akzo-Nobel epoxy primer. Great stuff. Expensive, but bulletproof. Dries very quickly and is ready to rivet after about an hour. After I ran out of the 2 gallons of Akzo that I used on almost everything, I switched to the spray cans of Napa self etching primer for the few remaining bits I needed to cover. It holds up pretty well if you let it dry for a couple of days. You can still take it off with MEK. The Akzo stuff barely smudges after a vigorous scrubbing with MEK.

 

[60av8tor]

I fully primed all of the interior surfaces with Akzo-Nobel epoxy primer. Great stuff. Expensive, but bulletproof.

Seems like I can't make up my mind about any of my build prep, but this is the route I'm about 99% sure I'll take.