Originally Posted by Trav
DTM primers like Axalta and Nason Ful Poxy are by default epoxy etching primers unlike epoxy primers like Axalta Corlar which is a standard epoxy sanding primer.
With DTM an acidic wipe down like any other primer is all thats required, an additional "etching primer" base is not needed.
Ful Poxy can even be used over bare aluminum. I use Ful Poxy on everything then top it with a 2K urethane primer.
I don't think those are "etching" primers but rather direct-to-metal without the need for etch primer. Epoxy primers are considered the gold standard for corrosion protection in the aftermarket. Looking at the SDS for that Nason stuff, there's zinc phosphate and under 1% of salicylic acid. The latter is an hydroxy acid more than likely used as a preservative.
When I took an auto body course at the local community college some 12-13 years ago, it was generally understood that etch primer was never to be topcoated with epoxy primer or applied under filler. We used Sikkens or Lesonal back then, but we kept a gallon can of PPG DP40LF in case we ever needed to use epoxy.
DTM primers like Axalta and Nason Ful Poxy are by default epoxy etching primers unlike epoxy primers like Axalta Corlar which is a standard epoxy sanding primer.
With DTM an acidic wipe down like any other primer is all thats required, an additional "etching primer" base is not needed.
Ful Poxy can even be used over bare aluminum. I use Ful Poxy on everything then top it with a 2K urethane primer.
I don't think those are "etching" primers but rather direct-to-metal without the need for etch primer. Epoxy primers are considered the gold standard for corrosion protection in the aftermarket. Looking at the SDS for that Nason stuff, there's zinc phosphate and under 1% of salicylic acid. The latter is an hydroxy acid more than likely used as a preservative.
When I took an auto body course at the local community college some 12-13 years ago, it was generally understood that etch primer was never to be topcoated with epoxy primer or applied under filler. We used Sikkens or Lesonal back then, but we kept a gallon can of PPG DP40LF in case we ever needed to use epoxy.