Primer To Bare Steel
- Thread starter Soft Cars
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If I am down to bare metal on a larger area or a full panel 2K epoxy then a colored poly primer to block it out, for small metal parts that have been blasted and clean self etch then top coat. This is a good overview.
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Differences Between Epoxy Primers and Self Etch Primers | Auto Repairs Direct
Both provide corrosion protection, and both can be top-coated with primer surfacer. Click here to read more.
It depends on what you are doing, if there is any rust repair or filler involved then you want an epoxy first not etching primer.
If it is just over bare metal you use a primer filler over the etching primer. if doing something like an engine cover you can spray the enamel over the etching primer.
If it is just over bare metal you use a primer filler over the etching primer. if doing something like an engine cover you can spray the enamel over the etching primer.
Correct but a poly primer in the correct color for the tope coat is a good idea if you want to block it out (it wet sand very easy) and save some expensive paint. You can use it also on metal but the epoxy is better for preventing rust and is a very durable base.
I use this product and have it in both black and white, I mix them to the shade of grey desired if need be.
I use this product and have it in both black and white, I mix them to the shade of grey desired if need be.
Nason SelectPrime 2K DTM Urethane Primer Quart
A 2K urethane, direct to metal primer-filler designed to provide high build and an exceptionally free sanding film without shrinkage or sand scratch swelling.
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I suppose it would matter what the finish is on and what it is for. I can tell you on thing though. The a milspec finish on Kalashnikov rifles is a self etching primer, and it is tough not pretty.
In high salt conditions "they" say to use a high zinc primer.
In high salt conditions "they" say to use a high zinc primer.
I use anything from 80 -120 grit, you want something the primer to "bite" into, once the primer dried but not overnight cured spray the poly primer right over it. The poly primer also uses a hardener, then leave it cure a minimum of 24 hrs sometimes I do something else and let it go a few days. I use alcohol to wipe the metal down before shooting the primer.
You will see the deep scratches in the metal in the primer, that is when you block it out with 400 and water and finish it with 600 and water to level out the primer, the scratches will disappear. Work the block diagonally alternating directions on larger panels until it is flat, don't get crazy and sand through the base epoxy, if you go through the poly it is no big deal you a light spray in the damaged area will fix it then just give it a light scuff.
Clean it and give a it a light scuff with a grey pad then prepsol it and top coat. It is a lot of work but worth it, it is durable and will not peel.
If doing a rust repair and mig weld it, always always cover the weld seal with epoxy (regular JB weld is great) then epoxy prime before applying filler, once the filler is good epoxy primer again. This will seal the filler so it does not absorb moisture, most fillers with the exception of fiber impregnated filler like tiger hair are talcum based as is regular old school primer, it will absorb moisture from behind through the slightest pin hole and show up as a bubble in the paint, the bubble is filled with water even though there are no chips in the paint.
At that point the rust has already returned under the filler. Done right I have rust repaired rocker panels going on 15 years with no sight of rust returning so yes you can repair rust successfully but it is a proccess that must be follower to the letter.
You will see the deep scratches in the metal in the primer, that is when you block it out with 400 and water and finish it with 600 and water to level out the primer, the scratches will disappear. Work the block diagonally alternating directions on larger panels until it is flat, don't get crazy and sand through the base epoxy, if you go through the poly it is no big deal you a light spray in the damaged area will fix it then just give it a light scuff.
Clean it and give a it a light scuff with a grey pad then prepsol it and top coat. It is a lot of work but worth it, it is durable and will not peel.
If doing a rust repair and mig weld it, always always cover the weld seal with epoxy (regular JB weld is great) then epoxy prime before applying filler, once the filler is good epoxy primer again. This will seal the filler so it does not absorb moisture, most fillers with the exception of fiber impregnated filler like tiger hair are talcum based as is regular old school primer, it will absorb moisture from behind through the slightest pin hole and show up as a bubble in the paint, the bubble is filled with water even though there are no chips in the paint.
At that point the rust has already returned under the filler. Done right I have rust repaired rocker panels going on 15 years with no sight of rust returning so yes you can repair rust successfully but it is a proccess that must be follower to the letter.
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