The definitive PPG Deltron Paint thread

I just got back from a two-day paint training session that I helped organize. The class was held at PPG's South Windsor, Connecticut training facility and was attended by 8 car nuts, including three GT40 builders and the owner of an ERA GT. It was two full days which included a fair amount of hands-on spray application time with a number of different products. The $100/day course fee even included donuts and coffee in the morning, a nice lunch, and sodas/drinks. It was, by far, the best $200 I've spent on my GT40 to date.

Our instructor, Jeff Sommers, was very knowledgeable and, of course, he was a car nut himself. This course was customized to our needs, many questions were asked and answered, many stories were told, many discussions went off on tangents, but we all enjoyed it immensely. The course was a variant of PPG's Certification 21 training, with lots of emphasis on both fiberglass prep and paint as well as steel-bodied muscle-car restoration and finishing, while auto-body-technician stuff like blending and paint matching was de-emphasized. We were provided with the opportunity to use PPG metal prep products, self-etching primers, surfacers, sealers, single-stage acrylic urethane, basecoat, and clearcoat. Jeff also demonstrated a wide array of other products, from nifty sanding blocks to UV-activated primer that dries in two minutes. I brought in two nostril panels from my GT40 that I thought were ready for priming and Jeff laid a sanding block to them and showed me how wrong I was - we got a lesson in figerglass prep right then and there.

There was also good car-guy stuff – we went and raced go-karts after yesterday’s session then drank beer and ate chicken wings and burgers and engaged in some serious banch racing. A great group of guys!

I would highly recommend that you seek out similar training if you want to paint your own GT40. I'm not an artisan and it’s been 25 years since I’ve sprayed a car, but I am now confident that I can paint my car and achieve very good results.

Anyway, in keeping with the title of this thread, I thought it would be a good idea to put some of the stuff we learned down in writing while it’s still fresh in my mind. One thing I found to be helpful was Jeff’s willingness to tell us specific product types to use. All the paint products we used were from PPG’s Deltron line, and Jeff’s recommendations were geared toward amateurs with an eye toward ease of use and forgiveness of the various products.

Let me start by laying out, in order of application, the Deltron products that Jeff recommended. Then I’ll just throw out some random thoughts that we picked up. OK, here we go…

  • DX Cleaners
    • DX330 solvent based (OK on metal and gelcoat, but DON'T use on raw fiberglass)
    • DX 394 water based (OK on metal and gelcoat, but DON'T use on raw fiberglass)
    • DX103 alcohol-based (this is the stuff to use if you've sanded through gelcoat anywhere)
  • DX metal treatments
    • DX 579 metal prep (cut w/ water for aluminum)
    • DX520 metal conditioner (use after DX579)
    • DX533 aluminum conditioner
    • DX503 aluminum conditioner (alodine)
    • DX501 (clear version of DX503)

PRIMER (primer refers to coating of bare metal)
  • DPX171 self-etching primer - best for sheet metal
  • DPLF epoxy primer - 6 colors, best for castings, forgings (don't apply over DPX171)
  • NCP270 (red) or NCP271 (gray) corrosion-resistant primer - apply over sanded original finishes or over primed or properly treated bare metal
  • Block to 100 grit

The above applies to metal prep and priming, below applies to both metal and fiberglass filling and finishing

  • 3M Rage lightweight body filler
  • Marson Platinum body filler (smoother texture, flows easily for finish filling)
  • Finish to 100 grit

  • MX241 - ideal for fiberglass bodies; "liquid bondo". Being replaced by MP243.
  • Finish to 220 grit

  • DPS3051 V-Prime acrylic urethane surfacer (DPS3051=white, 3055=gray, 3057=dk gray; do not use body filler over this)
  • DAS2021 acrylic urethane sealer (DAS 3021=white, 3025=gray, 3027=dk gray)
  • Finish to 400-600 grit

  • K93 tintable primer surfacer/sealer (use DMC base, not DMD)
  • Finish to 400-600 grit

  • NCP271 (OK to use body filler over NCP271)
  • Finish to 400-600 grit

  • Deltron 2000 DBC basecoat
    • DT885 is the normal recommended reducer
    • add 1.5 oz DX57 activator per qt
    • apply 2-3 coats until hiding is achieved, 10 minutes between coats

  • DCU2002 Concept high-solids polyurethane clear
    • Mix 4 DCU2002 to 1 DT reducer to 1 DCX61 hardener
    • apply 2+ wet coats, allow 15 minutes between coats

Some random notes and observations:

  • These urethan paints are MUCH better quality and longer-lasting than OEM paint.
  • I'm going to prep the inside (bottom) of my front and rear clip with DX103 and paint with black DPLF epoxy primer.
  • I'm going to put together a group purchase for AFS sanding blocks. Really nifty. PM me if interested.
  • Spray isocyanate paints with supplied air or with respirator ONLY IF properly fit and fit tested.
  • Get a good spray gun.
  • Spray 6"-8" from surface keeping gun perpendicular to work and using 50% overlap between passes.
  • Learn how to test your gun and evaluate the spray pattern and adjust as necessary.
  • Understand the proper gun setup parameters for each product you spray. Fluid tips from 1.3 to 1.8 mm for products listed above. PPG provides technical data for a variety of guns.
  • Use 5/16" fitting at gun; 3/8" air line for HVLP.
  • Polished aluminum panels can be clear coated by using a product called Matthews Spray Bond with equal parts DT reducer, stirring, applying one wet coat, letting solvents flash off for 15 minutes, and applying clear coat.
  • The term "primer" technically applies to coating over bare metal.
  • 3M makes a nice system that allows upside-down spraying out of an HVLP gun called PPS.
  • Pearl coats require "walking the side," as individually-pearled panels will look different from one another.
  • PPG makes a product called Aquapel that is 10X better than Rain-X.

That's all for now. Thanks for reading.:D
Did you take Ron along to this event, if not you should email him this info in case he missed it.

Sorry Ron couldn't help it, Mark great thread.



Mark, great information - thanks. As a back yard paint guy who has produced some very nice finishes over the last 20 years I can appreciate the need to keep updated on the latest technology (not doing so tends to produce orange peel and dull/uneven finishes!). Half the problem is keeping up with the product terminology.

The products are changing so fast that you can't just simply arrive upon a system of primer/paint/clear that works for you and stick with it for 10 years. So, again, thanks, great update.

Ron Earp

Steve, wish I could have gone but had too much going on with car prep for Daytona. August is a busy month carwise, and family wise with six family birthdays!!
Without a doubt the best 200 bucks I have spent while building this car, and the most fun I have had in a while. Many thanks Mark for arranging such a valuable experience for us.

Mark I also wanted to say thanks. Your arranging this was a godsend for those of us who got the opportunity to attend. The afterschool activities were great too. For any of you who are about to embark on painting - a course like this is really cheap insurance to a really good paint job and a great confidence builder. For me one of the best parts was there was a lot close coaching while you were spraying paint. Surely the entire class left with the feeling that not only could they paint their own car, but that they could do it as well as 90% of the shops.

I used to sell the "Aquapel" and it does work well, it lasts MUCH longer than Rain-X but does not shed water quite as well. I just used my last ones on our new shower doors!

When it comes to paint materials, never cut corners. Go with one system and buy the good stuff. The urethane paints now can be finessed to look better than the old lacquer ever thought of and last for a period of time that the old stuff could only dream of...

And as you found out, 90% of a quality paint job is the prep. The "spraying" operation is the easy part! With a good HLVP gun and proper materials most anyone can lay down a nice paint's what it is covering that makes the difference!
Steve2 said:
Surely the entire class left with the feeling that not only could they paint their own car, but that they could do it as well as 90% of the shops.
I think you're right, Steve. Now all we need is a $50,000 downdraft spray booth. And a couple $400 guns. And a new $1,000 compressor along with another $800 worth of air tools, air lines, fittings and filtration equipment. And a couple hundred more for those nifty flexible sanding blocks. Plus a few hundred more for tape and paper and abrasives. And about $1,500 for actual paint supplies. Oh yeah, and a couple hundred hours of labor.

Are we sick or what? :D
I'm a body & paint man. I would recommend to, "TINT" the epoxy (or other) primer to come as close to the base color as possible. This way, if you chip or deep scratch the base, you'll see less of the primer color. I also did this to my engine paint, which is the same color as my cobra body color. This method also helps when touch-ups are needed. Just my 2 cents worth.
Mark, you forgot a few things; the million dollar building to put all that in and the permits from the town. That's after you find a builing that is located on land that is zoned for auto body work. The hazardous wast desposal is another little cost. Also, the one thing that I hate; the insurance! If I had all that money, I wouldn't have to work!
  • MX241 - ideal for fiberglass bodies; "liquid bondo". Being replaced by MP243.
  • Finish to 220 grit
A quick update. I was at the PPG paint store today to pick up some primer and they were unable to get me either MX241 or MP-245. The equivalent product is PPG Shop Line JP205 high-build primer, only available in gray.
Bill, I paid about $68 for a gallon of the JP205 yesterday. It came with a few tubes of hardener.

John, you use an alcohol-based cleaner on raw fiberglass, like DX103. The solvent- and water-based cleaners will not dry completely when they get into pinholes beneath the gel coat and they will cause all manner of problems once they are "locked in" under a coat of primer/surfacer.

I should have read this thread again a month ago. I stripped and repainted one of the rear quarters on the Corvette just to have it bubble up a week later. The problem must have been the solvent-based cleaner I used before I painted.

Excellent thread BTW.


Sorry to hear about the Vette. :mad:

Don't know how much the "DX103" Mark speaks of is per gallon. On our aircraft at work, the ONLY thing we use to clean something before painting is 100 % Isopropyl alcohol (isopropanol). Be careful with sealing the can of any alcohol based product and try to keep it in a cool DRY place, as it will have an affinity for H20. You certainly don't want that sucked into your gelcoat or glass substrate!