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DTM primer questions

25K views 37 replies 11 participants last post by  deadbodyman 
#1 ·
I have been painting for almost 12 years so I am relatively still inexperienced and I have noticed a lot of suppliers really pushing the use of epoxy primers after blasting, stripping or any use over bare metal. My question is why go to the extra steps of using the epoxy when there are several reputable DTM 2k and high build primers available? If using the steps recommended by some manufacturers you would need 3 or 4 different primers for every job. Epoxy, high build, 2k, and 2k sealer. I remember the days of etching primer and glass jars for all over bare metal and I could see using the epoxy or etching for those jobs, but is it really beneficial for small collision type repairs? I am not arguing the use of epoxy, just wondering why create an additional step and more expense and supplies instead a DTM 2k or high build? I guess the short version of this question is why epoxy and not DTM 2k?
 
#3 ·
Cars come with epoxy primer underneath finish/paint and most auto body shops should restore it to pre-collision condition and that's where epoxy comes into play. Realistically speaking most people won't own their cars 10-20 years from now but top end body shops still have to make sure they put out a good quality paint job. Usually a decent body shop will warranty their work for lifetime of the car, so they wouldn't want you coming back with rust, peeling, etc issues
 
#5 ·
Your absolutely right ,theres way to many steps and the extra expense plus the drying time between primers,what a PITA... wouldnt it be nice to have an epoxy primer thats also buildable if you need it too so you only need one primer for the whole job what about the sealer lets include that too,One primer for all your needs...and lets keep the price down to around 150.00 a gal and an ez 1:1 mix ratio so you actually get two sprayable gal.and when reduced 10-40% it makes a great sealer....and lets have a tech hot line thatcan answear any and all paint related questions for the pro's AND newbies..
Sounds like a dream dont it....
SPI epoxy primer
 
#8 ·
First off nothing sticks like epoxy (spray glue) and as deadbodyman says you can use this particular epoxy (SPI) all the way through start to finish (sealer). One of the latest cars I just did I did use this epoxy as a finish primer over a spray poly instead of the 2K urethane and was quite happy with it, it does block out pretty good. And the savings are quite high as one two gallon setup should be able to do a whole car start to finish.
 
#10 ·
There are some high end Corvette painters that use only SPI epoxy start to finish and even do their blocking with it..I am a bit lazy and use the Spi epoxy to prime with and their 2k for blocking as the 2k sands a bit easier. Still only 2 primers plus base clear material. Labor is a big part of the deal and the SPI has saved me a great deal of work and heartburn..

Sam
 
#11 ·
After just using it as a blocking primer I must say it does sand out pretty well for an epoxy, but I do my heavy blocking with a spray poly. So as far as the epoxy being used as a heavy filling primer, that is not how i use it. When I spray it as a 1 to 1 mix, unreduced I am at a point where everything is already flat and straight so I can start blocking the epoxy with 220. Once you break through the first skin (that has a shine to it) it sands quite easy. And they do claim it has a very good resistance to chipping. Can't really back this claim as I just started as a blocking primer recently (not driven yet).
 
#21 ·
i have used finish 1 2k JUNK IMO!!!

you must have used some really lower line Primers to think this stuff is High build or good?

i use Sherwin Williams products.

i use there P30 set-up and love it,very expensive but some of the finest 2k primer i have ever used.

as far as Epoxy SPI is top dog for me.

in collision repair i just don't have the time to use it from start to finish.

all Bare metal should have Epoxy cover it then go from there with whatever you want.

i always seal either with my P30 converted to sealer or Epoxy.

Travis.
 
#15 ·
Thanks for the info. I want to personally and publicly thank Barry at SPI for a lot of helpful info also. I talked to him today and I am very impressed at the customer service he provides and I haven't even had a chance to try their products. I look forward to trying them in the very near future.
 
#18 ·
I do it all the time I hardly ever use a sealer (even epoxy ) Only on high end super straight work do I use an epoxy sealer when I do seal I always sand it before paint.
If youve ever sanded an after market panel(like a hood )you;ll sand the primer off in many spots (I usually sand all that cheap primer completely off)or if you strip a panel and it dosent need any filler work you can reduce the SPI to 20-40% and after spraying two coats go right to paint,it flashes pretty fast.
 
#17 ·
Sure, why not? As long as there are no sand throughs on edges or heavy sand scratches anywhere, your epoxy now just becomes your sealer as well. This last car I almost did it that way but went the extra step to seal.............and gained nothing more than if I did it the way you just mentioned.
 
#19 ·
After completing the blocking there may be sand throughs or some variance in color like say you used a black epoxy primer and a gray 2k or something on that order so shooting a sealer makes the whole car one color so the base will lay down in a uniform way..Just seems to me to work better..

Sam
 
#23 · (Edited)
LOL!

i was stating my opinion on the product.

i used a few gallons of it and cared not for the product.

yes Finish 1 is the lower line of SW products.

just like Omni is lower line PPG does not make PPG junk.

just like Nason is lower line Dupont does not make Dupont junk either.

i have used all the lower line primers over the years and all were about the same okay.

the finish 1 for ME! was not what i wanted.

i have also used the upper lines of Primers and Epoxys from the 3 groups.

SPI epoxy IMO again just ME! is better than the other lines.

P30 2K is better than the others to me.

used dupont for 30 years,PPG 9 years Pro-spray a little less than 2 years.

i have only been with SW products for 6 months.(i got from them a stocked Mixing set-up and extras).

we all have opinions i was sharing mine.

Happy New Years.
Travis
 
#24 ·
Wasn't trying to ruffle your feathers. I guess I just misunderstood your post. I never expect the same quality from the cheaper lines of the big companies but sometimes it what the customer wants. A good example is a car I have lined up. The customer wanted to use PPG from beginning to end. After I called and priced everything, he changed his mind and decided not to spend $2100 on materials alone.
 
#25 ·
no feathers ruffled at all :thumbup:

i have used tons of the cheaper line Primers.

none of them imo are really worth a crap.

i have used and really like SPI products for a few years and there Primers are top notch with a nice price to boot.

i got into the P30 SW Primer and P50 when i got hooked up with them and think its good stuff but the price sucks!



DTM primers i have never felt safe using on large open areas of bare metal.

Etch primers are 70s tech.imo

Epoxy all the way on Bare metal.

Everyones(top companies PPG,Dupont,SW,Spies ect.) products if you use them throughout are way over priced!



Best wishes Travis.
 
#28 ·
I like simple solutions. Also I will use a paint system until it fails one time, then find something better. I also avoid new products for a couple years, until the manufacturer works out the "early production problems". When I get a system that works for me every time, I will NOT change it unless it fails. (Yes... they do reformulate products to meet EPA standards and such... and it usually leads to problems. I will not use the latest "trick-of-the-week" system, when mine is working just fine.

I have used 2K primer only for about 20 years with zero failures. Sand the metal good, then metal prep 30-60 minutes before primer, and NEVER has adhesion problems. The only time I would consider epoxy first is if it will be left in primer and exposed to the weather. As far as wetsanding, I do it on every job, and then seal and paint. No problems with this in 20 years of full time work.

I know I am a dinosaur... but I guarantee my work for as long as they own the project. That takes confidence. I like Marhyde's Ultimate Primer.
 
#32 ·
The 60's ....No I painted my first car in 76 (at 16) did bodywork since 14yr...
and yes any of the primers of today are much better than what we started out with ....BUT I really feel the guys that started out using 2k's are missing a big part of the learning curve by not learning all the steps to get lacquer primers to work right...for instance you could NEVER prime over something finished out in 80 grit which is fairly common today....
 
#33 ·
Still more we have in common! Yes... lacquer primer was terrible for shrinkage into a porous surface. I did a lot of Corvette restos in the '80s, and switched to enamel primers, since the early Vette 'glass was sooooo open and pourous! At least the enamel primer would not come back and bite you six months after it's painted!!! :-(

Also... If you don't count spray painting my bikes and model cars... I painted my first real car in High school, in '65, at age 16. :)~ "My brother from another mother!"
 
#36 ·
I do a lot of chem stripping and all I can say is you can always tell when youve hit the epoxy.2k strips right off, epoxy is a little tougher always requiring a fresh coat of stripper just for the epoxy...
applying materials is one thing but removing them tells a lot more...
You never really know about the materials or your proceedure untill you do a job and have it come back damaged again ....this also tells a lot...
 
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