Primer paint?

[1917businesscar]

I painted my Dodge Brothers suspension parts last April with STEM self etching black primer then because of back problems they were put in a shed as soon as the weather warms up I'm wanting to put a final coat on them. My question is what do I use to clean the parts. I've been told I have to sandblast again (this I don't want to do) and been told to clean with Windex all the parts have been sandblasted and primed with a good primer just clean the dust off and paint its just suspension parts. So just wondering if anyone had this problem and what they did.

[nearchoclatetown]

I don't recall ever hearing the name Stem before. Perhaps you should check with your paint dealer. The body shop I had do my work said to always use a self etch primer on bare metal, as you did. AT most I would think you could use scotch bright to rough up the surface before putting your top coat on. That is all they did for new replacement sheet metal which would have the same effect as what you have. Those parts are primed at the factory weeks or months before be shipped to a shop to be installed. 

[Mattml430]

As per Doug said if there is no rust bursting back out of the parts give them a rough up with some 240grit or scotch brite. Give the parts a good clean before painting. 

[jpage]

I've had parts primed with self etching primer for almost 15 years with no issue. I'd just scrub them down well to get the dirt and film off of them, scuff them down and reshoot with a good primer. If you are doing any filler work on them, do it before the final primer coats. If there is a substantial amount of rust, then your best bet would be to reblast them. After the primer sets then finish coat them.

[22touring]

nearchoc said:  "The body shop I had do my work said to always use a self etch primer."

 

I do recognize nearchoc's expertise, but don't the product data sheets say you shouldn't spray self-etch over freshly-blasted or prepared steel?  Doesn't self-etch need some rust to react with, or else it doesn't adhere properly?

 

The body shop I go to says you should spray epoxy primer over freshly-prepared steel because it prevents rusting better in that situation than self-etch does, FWIW.

[nearchoclatetown]

No expert here. The shop I hung out at claimed with all the good stuff gone that is why they used self etch first, then a regular primer, usually epoxy on top. Even if they sanded through to bare on a small area like on an edge they would put self etch on. I am sure there are different ways to do this. 

[businesscar1917]

All parts were sandblasted and no rust has appeared the only part I have a problem with washing would be the differential with the bare steel it also shows no rust I guess I'll wait till a good warm day and blow it off with air when done. Well other than 2 parts on the engine I'm waiting for hope to have a original 1917 running frame by May the rest is easy I just find a good business that does body work and painting while I work on the wooden wheels Thanks for the info  Jim

[nearchoclatetown]

Jim, I will add this here. I just got the new DBC magazine and your article is very good. Thanks for writing it.