Hello everyone, had a quick question on ppg primer , more specifically which catalyst for colder weather?

I plan on using the same dp50lf grey that I have been using I think I’ll buy a gallon as opposed to the qt as it seems to be a helluva lot more economical, previously I have used the dp402 catalyst and no reducer, shot with a cheap o spray gun with a 1.4 tip , now I’m just sealing at the moment , I can heat my garage up pretty well I normally keep it at 70 if I’m working out there , but as the heater blows within 2 feet of the car and it’s electric by the way I plan to heat the garage up above 70 , turn the heater off , spray ( panels) and let it cure before turning the heat on ( 60 minute redcoat window with the 402, I believe it’s longer with the 401 catalyst,

next question I can add a little reducer but if I’m using this as a sealer should I spray unthinned?

any advice would be welcomed

 

If using it as a sealer prior to paint, I would reduce it. If using as a sealer prior to filler or primer surfacer I wouldn't. Tech sheet calls for 2:1 or 4:2:1 with the 1 being optional reducer, so basically whichever option works best for you in what you're trying to achieve. It will definitely lay down better with the reducer.

Also, the re-coat window on that is 1 week. The 60 minutes you're referring to is either the induction period or flash time required before topcoat.

 

Thank you sir, yes it’s going down before filler so I won’t reduce it, I used the wrong jargon it was 60 minutes before top coat

 

Yes, and you want to exercise patience with this. In cooler temps you need to wait significantly longer. Once you coat over the epoxy it will slow down the cure even more.

I personally wouldn't wipe filler or put primer on it until the next day, or at least until several hours have passed.

 

Thank you that will be my plan, I will keep the garage space temp up and will wait , will allow me to move on to a different panel , I believe the garage takes some time to cool down after I turn the heat off , I’ll ensure it doesn’t go below 60-65 degrees

 

There's no catalyst speeds like reducers. But having the garage at 70 is plenty fine. Recoat time is only 10-15 minutes @ 70deg, so you'll be fine especially if painting the whole car. I've done the same - heat up garage, turn off heater, spray, open the door to get most of the paint mist out, turn heater back on. For this I would mix a batch, spray whole car, flush out air in the garage, then it's ready for the next coat. You'll be good.

 

There are 2 different catalyst speeds for this primer. Also, the re-coat window is 60 minutes(30 minutes with the fast activator) to one week. That is at 70 degrees, it's longer for cooler temps. Recommending re-coat in 10-15 minutes might be fine with a urethane sealer, but can get you in a world of trouble with epoxies.

In this circumstance I would strongly recommend the faster catalyst DP402LF as the flash/recoat times are shorter and it doesn't require an induction period, so it will be much better suited for cooler temps and smaller areas like when doing a panel at a time.

 

OK, I was just reading from the DPLF tech sheet I found that said recoat time is 10-15 minutes for either catalyst. The 30 to 60 minutes is for topcoat or filler.
I don't know that I would call 401 vs 402 a "speed" thing like reducer speed where we're talking about temperature at apply time and trying to make sure the paint lays down correctly - e.g. dt870 vs dt860. That was the topic here - temperature in the garage.
401 has a 72 hour pot life! Seems like a completely different use case to me, and the tech sheets imply it's really meant for flexible parts.

 

Oddball thanks for your input , I have the faster catalyst anyway but need to get more , I didn’t hear the garage last night and I went out this morning it was still above 60 , it’s fairly mild here in New Jersey still, I’m just over thinking which I tend to do it causes me paralysis from moving ahead lol I just need to get on with it , damn the torpedoes! Full speed ahead lol

 

anther source of info, these guys helped me a bunch when painting my car


https://www.autobody101.com/forums/



Fred

 

Yup, just lay it down. If something goes wrong you can always do it again!