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Cleaning kit parts before priming

R

rv12iS-builder

Well Known Member
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Now that Naphtha is extremely difficult to find in California, what's everybody using to wipe down kit parts before applying self-etching primer? Isopropyl alcohol? Lacquer thinner? Dawn dishwashing soap and water?

Thanks,
 
Denatured alcohol

I use denatured alcohol or mineral spirits. Whichever happens to be within reach at the time.
 
I've seen mineral spirits recommended, and I use that to remove sticker residue and other gunk. My final wipedown is usually with some OMNI reducer, left over from an automotive paint job several years ago. It's thinner (reducer) for acrylic enamel. But like Xavier -- whatever's handy.
 
Cleaning parts

Lacquer thinner is my standard cor rattle can prep for tiny parts.
Before spraying the main primer, AeroGreen 4110.
 
I haven't gone the rattle can route (tho it would be way easier!). Acetone, Alumni-prep, and then StewartSystems EkoPrime works really well for me (and then in some cases, JetFlex WR as a top coat)
 
Dupli-color acetone from O'reilly auto parts has been my choice after S.E.M. was no longer available due to the newer VOC laws in AZ.

cm521_030810.jpg
 
I'm still playing around with methods of prepping before I use SEM self etching primer.

So far, what has worked the best for me is a very long process of scuffing, acetone, then dawn soap/water, rinse with tap water, then rinse with distilled water.

That process was taking forever and so the last batch I sprayed, I skipped the acetone step but kept everything else the same. The batch didn't come out too well. I had several areas of primer "lifting". I'm not sure if the prep method was bad, or if it was due to that I also had switched from using rattle cans to spraying it with a HVLP gun. It took a little getting used to.

My next method that I am going to try, is using SEM's no voc cleaner. I'll experiment with this on some scrap parts first this time.

All this brings me to a question that's been lingering in my mind, but I'll ask on a new thread in the primer section so I don't hijack this topic.
 
clutch22 said:
So far, what has worked the best for me is a very long process of scuffing, acetone, then dawn soap/water, rinse with tap water, then rinse with distilled water.

That process was taking forever and so the last batch I sprayed, I skipped the acetone step but kept everything else the same. The batch didn't come out too well. I had several areas of primer "lifting".
Click to expand...
After cleaning with mineral spirits or acetone to remove adhesive residue and oil I scuff with a maroon Scotchbrite pad, wipe down with thinner (or acetone if it's handier), shoot SEM primer (or Stewart Systems Eko-Prime if it's a large batch of parts). Zero problems. A solvent wipe will leave zero residue or deposits... soap & water, maybe or maybe not.

I figure that once the metal is cleaned of adhesive and gunk, the scuffing will provide some mechanical adhesion and the solvent wipe ensures there are no oils left. I wear nitrile gloves while doing the wipedown and painting, to protect my skin from the solvents and the parts from my skin. If I'm shooting SEM primer I also use a 3M respirator half-mask with the pink P100 filters good for particulates and "nuisance level" organic vapors. I don't even smell the solvent until I take the mask off.
 
Shower cream and acetone

If necessary, I start with removing remains of adhesive labels and oily fingerprints with alcohol.
Then, after scuffing the parts with maroon Scotch Brite pads, I clean the parts, first with soapy water (and yes, I use the same shower cream products as for myself :eek:), rinse them very well and let them dry.
Then, before priming, I use acetone to fully degrease and to take away any rests.

Even though you may laugh about of using body shower cream, I think any substances with degreasing effect will do the job. And as I take large parts to the shower booth, the soap is already there :D
 
Couple of things to note. Cleaning before sanding or scuffing is recommended. Is it necessary, probably not. However, cleaning before sanding eliminates the chance of grinding contaminates into the surface.

Self Etching primers make a very good base for other primers even without sanding or scuffing, at least the SW product. The etching process itself makes a pretty good bite. Unless you apply it too thick, which is a common problem. I personally did not take the time to scuff anything that was simply etched, like ribs inside surfaces of skins, etc.... I chose to scuff surfaces that I etched and then primed or painted to give an extra bite. Professional painters scuff the mustard off of things, probably for a good reason.

I like Kleen Strip Prep-All. It has a variety of solvents in it working together as a degreaser and surface prep. It is not that expensive and a gallon goes a long ways. No need for any other cleaner or surface prep product. Wipe it on with a clean rag, let it sit for 1 minute, wipe off with a clean dry rag, done. You can buy it at most auto body shops. This product will reduce you prep time.
 
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PreKote, SEM

+1 for PreKote. No soap, no solvent, just Scotchbrite scuff with PreKote, water rinse, dry, then shoot with SEM. Superb results and no clean up hassles, VOCs, etc. Wear gloves though, or the PreKote will do a bang up job of degreasing your hands.
 
225S and 226S

Don't know if it's still available, but I used acetone plus DuPont 225S and 226S prior to primering. It was easy to use and my DuPont Variprime, self etching, primer has shown no signs of letting go. John
 
I'm amazed at all these steps! Wow.
1. Wipe with acetone. Cheap by the gallon at big box.
2. red Scotchbrite pad scuff.
3. Wipe with acetone.
4. Spray rattle can self-etching aluminum primer - Home Depot Pro series or Marhyde from Oreilly Auto Parts.

As previously said - you'll have to sand it off if you want it off.
 
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