PPG Epoxy Primer DP90LF{lead free}

Posted By: 340SIX

PPG Epoxy Primer DP90LF{lead free} - 11/26/08 10:11 PM

I read the P sheet and it says to top coat with paint or a 2 part primer within 7 days while it is still in the window or it must be scuffed and retoped with more DP.
I asked the paint store if after that window, if it would be ok to scuf and top coat with 2K primer with out the coat of DP. They said it should be ok even though I have broken the rules.
Reason for wanting to skip the re-coat of DP is it is very costly.
I will be blasting some "Donner panels" and using the DP to keep

them for futher use down the line.
I know you can just top coat E coated panels with a light sand or scuffing so should the DP be that much differant?
I also see this being a problem while working on the car
{ie} Say ya get the engine bay ready, coat it with DP and then move one to another section the same thing would happen

Posted By: Pacnorthcuda

Re: PPG Epoxy Primer DP90LF{lead free} - 11/26/08 10:55 PM

Why not just topcoat the DP with the 2K then store them?
I would be willing to bet that scuffing the DP just prior to the 2K, in the future, would be fine, just as your paint shop said.
PPG does have a good tech line--I think the number is on the Tech (p) sheets? if not its on the net, Ask them. I got soem realy good advice from them regarding all the different hardeners that can be used with DCC Concept.

Posted By: Challenger 1

Re: PPG Epoxy Primer DP90LF{lead free} - 11/26/08 11:01 PM

Yea I hear ya Kevin, I've never done it so I can't help.

But I know what your asking, this has always caused me to start painting my work trucks after sand blasting and don't stop till I'm done with finish colors. Usally takes a couple days but I get em done with no sanding, scuffing and no recoating$$.

If were me I'd leave everything bare and blast everything right before paint. But I know not everyone has a blaster sitting around like I do.

It's the same thing with etch primer too. PITA

Posted By: 340SIX

Re: PPG Epoxy Primer DP90LF{lead free} - 11/26/08 11:13 PM

Quote:

Yea I hear ya Kevin, I've never done it so I can't help.

But I know what your asking, this has always caused me to start painting my work trucks after sand blasting and don't stop till I'm done with finish colors. Usally takes a couple days but I get em done with no sanding, scuffing and no recoating$$.

If were me I'd leave everything bare and blast everything right before paint. But I know not everyone has a blaster sitting around like I do.

It's the same thing with etch primer too. PITA

1)My plans we to cut out some donner panels
2}Then blast them clean
3}Prime with DP90lf
4}Later weld them in same as you do with the E coated repops you buy
5}Sand/scuff and reacot with 2K
6}Sand later and paint
Be realy hard to do it as the P sheet says for a resto, that runs on for quite some time{most of the time}
Guess I will shoot them a call.
I have some old DP on the car as well that will get 100% removed section at a time since it was not cleaned well before the DP40 was applied.
Car was redi striped and the shop was supossed to sand and wipe with laqure thinner and shoot the DP
instead the just shot on 2 light coats of dp and some is realy not stuck since it was shot over god knows what.
{ie}dirt grease oils ect.
They basicly stole my 5 gallon can of thinner, most of the DP and did a quickie shoot the primer on.
So now I am stuck when I do the car to strip all the DP off and shoot new DPlf on as I can in sections
I also tried to see and it looks like the old DP40 melts and comes off the bare metal with white rags and laqure thinner.
Was also thing I might just remove the old DP with a box of white rags annd 5 gallon can of wash thinner.Since I can not trush what they did to be stuck

Then scuff and recoat with the new DP.If not it will be DA with #80 or those 3-M disk

Posted By: DUSTER_340

Re: PPG Epoxy Primer DP90LF{lead free} - 11/27/08 01:16 AM

The 7 day window has to do with the ability of the top coat to have a chemical bond to the DPLF.After the 7 days you must scuff and then it is a mechanical bond.

Posted By: 340SIX

Re: PPG Epoxy Primer DP90LF{lead free} - 11/27/08 01:37 AM

Quote:

The 7 day window has to do with the ability of the top coat to have a chemical bond to the DPLF.After the 7 days you must scuff and then it is a mechanical bond.

Thats 100% the way i read it on the P Sheet for both the LF and the old non lf. Thing is the sheet says to coat after scuff with more DPLF like the 2K would not work.

Posted By: rabid scott

Re: PPG Epoxy Primer DP90LF{lead free} - 11/27/08 03:27 AM

DP90 is the "final color" for half my cars...

Posted By: 340SIX

Re: PPG Epoxy Primer DP90LF{lead free} - 11/27/08 03:31 AM

Quote:

DP90 is the "final color" for half my cars...

ever look at the dupont hot rod black it is single stage and looks nice! I am 99% sure it will be whats on my TA hood

Posted By: rabid scott

Re: PPG Epoxy Primer DP90LF{lead free} - 11/27/08 03:59 AM

Quote:

Quote:

DP90 is the "final color" for half my cars...

ever look at the dupont hot rod black it is single stage and looks nice! I am 99% sure it will be whats on my TA hood

Hell, if I was gonna spend that much on paint,I may as well put real paint on the turd!

Ever seen trim paint (like the black stuff on 80's-90's Mustang bumpers) fully covering a car? A buddy did his 1930 A-bone with it, turned out really nice!

Posted By: AdamR

Re: PPG Epoxy Primer DP90LF{lead free} - 11/27/08 01:18 PM

Heres some SEM Hot Rod black.

Posted By: Geno

Re: PPG Epoxy Primer DP90LF{lead free} - 11/29/08 04:15 AM

Your post got high jacked!

E-coat stands for Electro coat or Electrodispositioncoating which is the application method not so much the product.

http://www.clearclad.com/clearclad_resources/ecoat.htm

There are however epoxy based e-coats. But not all epoxies are created equal therefore they will all have different qualities. Similar but different. So yeah they are different.

As for what to do since you have lost your chemical adhesion you will have to go for mechanical and thoroughly sand (read your primer tech sheet for grit recommendations) the panels and apply your primer. All should be okay from there. Do however be careful of cut troughs. For engine compartments, door jambs, trunks etc. I would try to set myself up to apply two coats of epoxy and topcoat per recommendations. Fastest, easiest, durable and least costly in the long run!

Now on to the epoxy as a topcoat it will start to break down as it has no UV protectants built in. So when it starts to chalk up get ready to repaint. That is why DuPont makes a Hot Rod Black. It is a matted single stage that has UV protectants in it so it will hold up as a topcoat when applied properly. There are matting agents for single stage colors as well as clear coats. Just an FYI for those that were not aware.

Later,
Geno