Most of you know how negative I've been about powder coating. Well, I dipped my toe in the water & bought some very nice early intake plenums that had been powder coated. Apparently the coating wore off in several places during shipment (packed in paper). They're nice, but they will need to be refinished.

Questions here are:
How difficult is powder coating to remove?
Can it readily be painted over? If so, suggested process?

Pat

Pat,

The company I work for sends our aluminum extrusions to Valmont Industries for powder coating.

I called our local sales manager in Southern California with your questions and here is what he said:

How difficult is powder coating to remove: It can be done but might be difficult depending on your local environmental laws. There are effective strippers available to remove the paint but most states are no longer permitted to use. You may want to check with a local plater to see if they are permitted to use such chemicals.. Sandblasting is another option but may cause pitting.

Can it readily be painted over? If so, suggested process? He is not certain if it can be done but you would need to remove enough paint to allow for electrostatic conductivity. He said he would not recommend this as the powder is thick and needs a good bare or chem film surface to adhere to.

Hope this helps..

Raul

Pat - I just removed a bunch of it off some engine parts. It's tough. Some will come off easy and some will be a bitch. Even on the same part there were spots that took a wire wheel after using very strong paint stripper. The nooks and crannies are the hardest to get clean. The paint stripper gell made a mess.

I also tried soaking a piece in boiling water and that may have possibilities, or maybe using heat and baking it off. I think its more plastic than paint.

There are companies who will strip the parts. Its not that expensive.
I had a powder coated motorcycle frame, swing arm and misc parts done. It cost less than 80 bucks.
They just dip in a a tank and it looks like new metal when you get it back. Then just refinish however you like.
Some will say just use paint stripper.
When you consider the cost of that stuff, the time it takes, the MESS it makes and it is not that easy to get it out of nooks and crannies.

I think its way worth just paying to have it dipped.


This is who I used.
http://www.americanmetalcleaning.com/

Wow, Wore off in shipping? I just had these wheels powder coated last week. The powder guy had some blow through onto the polished lip. I had to use a hard buffing wheel with black diamond to get it off! A couple places I had to sand off and re-polish the wheels So your discription does not match what I had to do to my wheels at all.

Click to view attachment

Now, You can paint over the powder. You will have to sand blast or sand with like 180 grit for the paint to get enough tooth to hang on to the powder.

One other thing. One of the 928 guys blasted and powder coated his intake, bolted it to the car and destroyed his engine with the grit that was lodged in the intake. Intake parts need special care.

I just stripped ALL of the original paint from my engine tins using a product that you can get from Home depot.

It is called Industrial Purple parts cleaner.
It comes in a 5 gallon box/bucket for ~$35.
You are supposed to dilute it with water, but I used it straight, and I mean it cleaned the engine tins to bare metal.

The problem here is that you cannot use it with aluminum parts or it will etch the aluminum (maybe not so bad for intake manifolds ;-)

Stu

Just ship it back and forth a few more times.

It's really fishy that paper could have worn it off so easily. It wasn't shipped that way? Did it just change the surface quality, or actually wear into the coating? Pics? I hope this doesn't become your measurement for powdercoat quality, because that's not typical for a quality job.

My name Barry, and i powdercoated pat"s plenums. I asked pat to send it back and i would prep and recoat it free of charge. I did not recieve a reply back. I stand by my workmanship as a "hobbyist powdercoater" I have been coating for over 3 years and have done many small jobs for porsche friends and forum members only. Its my hobby that i enjoy and want to continue doing so. I cant for the life of me figure out how it became scratched or worn off in shipping by paper. Anyway, pat if your reading this please give me the opportunity to make it right. Ill even sandblast it with my media which is glass beads and not sand, to keep it from pitting, to remove the powder. Its a bitch, but ill take care of it.
regards

Click to view attachmentBefore shipping

Pat, I didn't think powder coating was in your vocabulary. I ran into a simular problem. Sandblasting.. no go. Chemicals.. no go. Took it to a PC place, and they baked it off. Came out perfect. Aircraft stripper is ineffective if your considering that. The shop said that a paint stripper called Ready Strip? could work with some effort. You'll have to etch the pc for it to get into it to work. Get if baked off or dipped, like previously suggested if you want it removed.

Barry - relax! I didn't out you & never intended to leave them that finish. You gave me a good buy & I'm content. Chill brother!
Pat

I am by no means a pro but this works for me. TAL-STRIP 2Click to view attachment

Just soak the things in a tub of brake fluid. After all the powder coating comes off you can rinse them with water and there will be no pitting or discoloration, just nice bare metal.

Kevin,

Don't know why I didn't think of that! Should work too. Try the soak process tomorrow. Hmmm, should I use DOT 3 or 4?
Pat

We removed it off a chassis one time with a torch. Burnt it off. The chassis was mild steel so everything was fine for a recoat. We wer just easy on the heat.