TheSamba.com :: View topic - urethane 2k sealer over NAPA 1k touch up primer?

Wed May 15, 2019 5:40 pm

Had a few spots I wet sanded primer too thin. Body expert at the local NAPA told me their "2 in 1 all purpose primer" aerosol would be compatible and have no issue. After applying, a Martin Senour help center tech replied to a previously sent email. He wasn't sure and gave me the traditional "try it on a panel first" answer and stated it was meant for only 1k rattle can project. On the can label, it clearly states "compatible with MOST automotive finishes." There are NO data sheets on this product or instructions online anywhere for this product. Does anyone know for sure if this crap will lift right up or turn to gum when I apply sealer? THANK YOU!

Fri May 17, 2019 9:52 am

Maybe my question was too specific. I’ll rephrase. The Martin Senour tech rep returned an email and stated the crud is alkyd based and says is usually only used for 1k products but the can states compatible with most automotive topcoats. Does a typical 2k sealer hold 1k aerosols down weeks after curing or does it usually wrinkle etc. when potent solvents from urethane applied? I’ve successfully done it many times with acrylic enamels, hardeners, and reducers...just not urethane sealers or topcoats. I applied some light coats of the spray max 2k epoxy primer to most of these spots later on for added protection, but could possibly still have issues I suppose. Any body guys know the answers here? I guess I could just shoot the sealer and paint and if it messes up in a few spots just sand it down, reseal, then apply and blend.

Fri May 17, 2019 6:00 pm

I think most people are likely to be very uncertain regarding whether you will have issues. Most experienced painters don't take the risk of mixing 1k and 2k (not literally mixing of course) products.

It would REALLY suck if someone here guessed and it lifted on you right?

Fri May 17, 2019 6:22 pm

Shouldn't sealer fix any spots you sanded thru?

Sat May 18, 2019 2:25 am

Can you paint crud? yes

Should you apply crud to car? no

Sun May 19, 2019 8:55 pm

The salesman that sold me this stuff said it was a hybrid and would work with no issue. I wouldn’t normally mix the products. The sealer I have states to not use over bare metal. I’m sure a few small spots won’t hurt anything but I used the aerosol instead. I used to work at a high end vw restoration shop and they use the 1k UPOL cans like crazy on every job they did.

Sun May 19, 2019 9:20 pm

I’ve done it before, 2k over lacquer primer. Not saying it’s recommended and only owned the vehicle for a short time, but I didn’t have any ill effects in the short term. However, im a firm believer that 2k products r superior, over time

Mon May 20, 2019 7:52 am

Quote: I used to work at a high end vw restoration shop and they use the 1k UPOL cans like crazy on every job they did.

If you knew this then can I ask why you asked the question?

Mon May 20, 2019 2:29 pm

^because they didn’t have the Upol in stock. I used the Napa version and originally had asked if anyone knew it would work. I found out it was alkyd based after the fact. Can’t simply remove it because I touched up over it in spots with epoxy.