Maxwell Man

[Eddie Adams]

I have been restoring a 1909 Maxwell for the last ten years and I used PPG paint to paint parts including the seat which is now upholsered with new black leather. I decided to have a body shop paint the rest of the car insisting on PPG paint for color match. The shop used PPG single stage DCC red paint to do the axles, springs and other undercarrige parts. I was there when he finished the paint it was like glass, it looked as if it had been dipped without any texture or runs! We went home and the next morning it was a disaster. There were millions of solvent pops all over the new paint. Since then we have spent countless hours trying different temperature hardeners, thinners and flash times. The last try was with DCX9 hardener and DT895 thinner which was recomended by the PPG Rep that came to the shop. After all that I bought some Dupont paint, hardener and thinner. It came out beautiful just like the PPG but it had no solvent pops. The only thing I have to get straight now is to get the color matched.
Has anyone out there ever had this solvent problem with PPG, if so please respond to this thread.

 

[Kong]

Are you sure it was solvent pop and not a poorly prepared (cleaned) surface or an incompatible base under it?

 

[TAZ]

Possibly too many coats. Sometimes on smaller parts, you can get carried away and put too many coats on.
Do a test panel duplicating everything, but put only about 3-4 coats on....actually, do 2 test panels, one with about 3-4 coats, and one with about 6-8 coats. See if the 6-8 coat solvent pops. If not, this could rule out solvent pop.
Maybe a very good close-up pic might help us figure it out here on the forum?!

Normally single state paints are very forgiving!

 

[Eddie Adams]

I am sure it is sovent pops. The PPG rep. looked at it and verified it was solvent Pops.
We have been really carefull in prep. All parts were sandblasted by a commercial stripping Co. and painted with PPG DP74LF red epoxie primer. Then we used PPG K36 sanding primer, after the sanding we used a light coat of PPG DP74LF for sealing. We then cleaned with a dry cloth and air, then tacked of with a comercial tack rag. All thinner and hardener was PPG.
Please remember that after we used Dupont over the PPG prep. work there were no pops.

 

[Eddie Adams]

We have done the test panels and both 2 or three or five coats have solvent pops. The PPG rep. painted a test panel all by himself while we watched and when he went home it was beautiful but the next morning it was covered with solvent pops.
When doing small parts such as leaf springs the solvent pops are not in the middle but all along the edges and especially between the leafs.
We are using an Iwata gun.

 

[TAZ]

Sounds like bad paint then.
Stir it up real good and look at it close in the can and see if you see any bubbles or a gritty looking substance.

My guess would be one of the toners was bad.

 

[Kong]

Well, its a mystery to me. I did notice that you are in New Hampshire, known for some pretty drastic weather changes in mighty short periods of time, and that in each instance it was shot and popped you let it set over night. Is there any chance there was a big temperature swing during the first several hours after the last of the paint was shot? I lost one (HOK products) last spring after the temperature dropped. It was in the mid 70's (F.) when I finished painting but then dropped rapidly into the 40's within the next couple of hours. That one sort of blistered up and then laid back down into a ruinous pool. Other than that about the only thing that comes to mind is old catalyst or as a real long shot it could have come from insufficient dry time between coats of the K36 that blew up through both your sealer (DP74LF final coat) and topcoat.

 

[Eddie Adams]

The pops appear to go through the finish paint but they stop at the sealer when sanding them out. However you may have hit on something. The weather hear has been very hot on most days and I know it was hot during painting, The temp. has been around 93 degrees most days in and out of the shop. At night it has dropped into the 70s at night but the shop was closed up at night and I don't know the shop temp. at night. My guess would be 75 - 80 inside at night. The temperature is the reason that the PPG rep. recomended we use DCX9 hardener and DT895 reducer, but no improvement was seen. They were new hardener and reducer because we did not stock them. These pops have occurred on test panels with no primer or sealer.