Painting steel parts

[N3UW]

I purchased the steel parts for my Partol wing from Mark at AviPro. I chose them to be unpainted. They were protected with a rust protective coating of some type (feels similar to boeshield). Any recommendations on what to clean it up with before I paint.

[dedgemon]

Try denatured alcohol. If that cuts it, great. If not, step up to lacquer thinner.

[Mark Moyle]

Carbon tetrachloride.... I joke. I use acetone Sent from my iPad using Tapatalk

[jaredyates]

If it is LPS, then it probably won't take much, since I think it's just petroleum distilates. Which paint system are you using? Polyfiber has their C2210 which would probably clean them up just fine. Are the parts already sandblasted?

[N3UW]

The parts are already sandblasted. acetone seemed to work well. thanks.

[Enewton57]

I use Naptha to clean everything to painted. It leaves no residue and cleans, degreases thoroughly. Use a two papertowel system, one wet with Naptha and follow up with a dry one. Steel parts get sandblasted. I like a 2-part epoxy primer and then top coat with a urethane enamel paint. A couple of light coats of each is sufficient.

[N3UW]

Eric and Others,
Your comment and Bobs note in the plans brings up a question. You said that you use a 2 part epoxy primer than a urethane enamel top coat on the steel parts. For the internal wing parts is the top coat really necessary. I am using AkzoNobel 2 part solvent based aircraft epoxy primer that when dry is impervious to about everything including MEK. Are there reasons that with this primer I would also need to top coat the internal parts? Thoughts folks?

[dedgemon]

Nope!
The epoxy primers are pretty bullet proof. The urethane topcoat is really just for looks. In issue in the visible parts of the fuse. The urethane is also easy to clean (slick). compared to the primer surface.

[Enewton57]

Might be I just put it on too thin but I used epoxy primer only on my internal steelers parts on the Bearhawk and a couple of years later found some surface rust. Make sure you get enough of it on to totally seal the part. Eric Newton - Long Beach, MS http://mybearhawk.com

[Enewton57]

Steel not steelers - dang auto correct got me again. Eric Newton - Long Beach, MS http://mybearhawk.com

[Collin Campbell]

I used a two part epoxy primer (PolyFiber EP-420). Bullet proof... No top coat. A light misting coat is OK for aluminum parts, but not so with the steel. On the fuselage, I used two coats, make sure it is covered real good. Don't want no rust...

Collin Campbell, (Bearhawk N370CC, Patrol, N180PB)
Bolivar, MO

[bergy]

Does anyone know if it is OK to prime blued//black oxidized steel without getting back down to the completely bared metal? Let's say you've either sandblasted or sandpapered your steel down a perfectly clean metal surface, then tig-welded on a fitting or for some other reason had to seriously heat the steel in the neighborhood. The recently spotless steel now has a patina like that of a brand-new shotgun .... beautiful shiny blue/black. Getting the area back down to bare metal again is time consuming. Since the blued finish is so good at preventing corrosion on a shotgun, it should be good enough on a Bearhawk too. Right? For that matter... when sandblasting, is it OK to stop eroding away the tubing when all that remains on the tubing surface is a microscopically thin transparent shotgun-like blued surface?

[S Lathrop]

The best source for an answer to your question is to get the recommendations from the manufacturer of the paint you plan to use.

There are chemical etching solutions designed for steels as a preparation prior to priming. I use PPG products and they have detailed instructions for surface preparation for their automotive/aircraft finished.

[zkelley2]

Does anyone know if it is OK to prime blued//black oxidized steel without getting back down to the completely bared metal? Let's say you've either sandblasted or sandpapered your steel down a perfectly clean metal surface, then tig-welded on a fitting or for some other reason had to seriously heat the steel in the neighborhood. The recently spotless steel now has a patina like that of a brand-new shotgun .... beautiful shiny blue/black. Getting the area back down to bare metal again is time consuming. Since the blued finish is so good at preventing corrosion on a shotgun, it should be good enough on a Bearhawk too. Right? For that matter... when sandblasting, is it OK to stop eroding away the tubing when all that remains on the tubing surface is a microscopically thin transparent shotgun-like blued surface?

You should be able to epoxy primer that no problem.

[davzLSA]

I like to de grease steel with MEK, after that I know without a doubt it is clean of everything.