self etching primer

what has been found to be the best self etching primer to use on the
inside of an aircraft?

I used and recommend the NAPA 7220:
https://www.napaonline.com/en/p/MSR7220

It is a little pricey if bought at the retail price but when I was building every 6 months or so NAPA would have a 1/2 price sale on the 7220. I would buy a case, or as many as the local store had in stock. I could keep a good stock on hand that way. About the time I would need more, another sale would role around and I would stock up again.

To my surprise, I found that different NAPA stores had very different prices for 7220. Shop around.

Jerre

It is more expensive but I found that the SEM rattle can primer gave more consistent better coverage but I have used the Napa one as well.

I used Variprime. 2 part mix but its not critical. I usually did it by eye.
I used an airbrush since the paint pot is tiny and perfect size for a dozen fabricated parts. No big overspray either, so I could paint inside (cardboard box paint booth) if I needed to.

In a pinch (ran out of Variprime), I used 7220 on some parts before getting some more Variprime. It worked OK and is still there after 7 years but for me it did not appear to etch as well as Variprime. I attributed it to single component vs 2 component mix reaction but that is speculation only. YMMV of course.

I used 2 quarts during construction which included complete tail interior, cabin, baffles, all 6061, fayed surfaces elsewhere.

The never ending primer topic...

I used Rustoleum self-etching aluminum primer from Ace Hardware, although probably at your local box store as well. About $4-5 a can and works very well with a good base for their satin gray finish as well.

The 360? spray nozzles work very well and worth the "big bucks" cost.

Another Choice

Try Cromax (formerly DuPont) A-4114STM Etch Primer - Gray/ A-4115STM Etch Primer - Green, available online or from some auto parts chains. In my experience, more durable than Napa 7220.

Primer

This is what I used

http://www.tcpglobal.com/SEM-39683_5.html?sc=115&category=11322545#.WXH5IOSWyF4

Superior adhesion to steel, aluminum and stainless steel

Very good results

Joe Dallas

rongawer said:

I used Rustoleum self-etching aluminum primer from Ace Hardware, although probably at your local box store as well. About $4-5 a can and works very well with a good base for their satin gray finish as well.

The 360? spray nozzles work very well and worth the "big bucks" cost.

Click to expand...

+1. Get mine at Walmart.

Do a test

Try a test. SEM, Nappa, Rustoleum. My bet is the SEM will adhere
The best. It's more expensive but Very good. I used it on my interior and
Have had no issues with adherence.

SEM Primer

Al

I agree

The only thing that compares is Zinc Chromate.

I used it on my 10 and it was nasty to work with.

Joe Dallas

agirard7a said:

Try a test. SEM, Nappa, Rustoleum. My bet is the SEM will adhere
The best. It's more expensive but Very good. I used it on my interior and
Have had no issues with adherence.

Click to expand...