Eastwood Epoxy Primer
I have purchased a gallon of Eastwood Epoxy Primer. It is a non-isocyanate formula.
I typically strip to bare metal and sand or sand blast. Then clean with metal wash or acetone and shoot. Two coats epoxy and two coats of chassis paint.
I am having paint adhesion problems on car parts (leaf springs, differential, brackets, etc.). Mostly, just notice that my final coat (ceramic chassis black) and epoxy seems to chip off together, and pretty easily. I thought these high quality paints should cure tough as nails. I expected better. Anyone have experience with either of these products?
Thanks - love this forum.
I wouldn't really describe Eastwood products as high end. It's only their price that's high end.
Originally Posted by TR3_Nut
If they're chipping from abrasion, stone chips etc that is a characteristic of a hard surface. They chip easily. Softer coatings absorb the impact rather than chipping off. The fact that the epoxy is coming with it says that your weakest link is the epoxy to metal point.
If your finish is failing the masking tape test (apply a strip firmly and peel it off and see if paint comes with it) It would appear that your epoxy is where the issue lies. When you use your metal wash, are you letting it dry completely? Metal washes are usually an acid treatment and are a different animal than an acetone wash and may need longer than the acetone to dry.
My experience with PPG's Omni line epoxy has been excellent with respect to adhesion. When shooting a sandblasted diff with the rear cover off I got some overspray on the oily section, thinking I would just wipe it off later. It stuck! I'd probably try that instead of the Eastwood stuff.
I absolutely agree with Steve, Eastwood is overpriced and the products can leave a lot to be desired. Switch to brand name paint products like PPG, DuPont, BASF etc.
Also, if you're using an acid wash it can make some primer not grip the surface because some epoxy primers have an acid in them and won't bond well with metal that has been treated with an acid wash or "metal conditioner".
Thanks for both of your responses. It's not all good news for me but it will make my future work better. Hope the local community hazardous waste pickup won't mind receiving a gallon of epoxy primer with hardener....
Rust and epoxy primer
OK, another question. If I'm shooting Omni primer and sh*tcanning the Eastwood stuff, can I shoot over a fender that was sand blasted if there is very minor flash rust or do I need to somehow treat the fender prior to shooting with epoxy? The rust is really minor and now I'm concerned that treating with metal etch isn't the right way to condition prior to primering this part.
I would convert the rust with a metal treatment. I use Rust Mort under Omni epoxy all the time with great results. Len and the gang here swear by Picklex, which Len sells in the store here. I have never tried Picklex, but Len, who has used both, assure me that I would throw rocks at my Rust Mort once I've tried picklex.
Originally Posted by TR3_Nut
My method is to work it in well with a scotchbrite pad, let it sit a couple of minutes and wipe it down well removing any excess. Let it dry thoroughly. Light scuffing with a dry scotchbright to ensure any deposits (dried acid wash) are removed. Blow it off and shoot your epoxy. Apply whatever is going on top of your epoxy as soon as the epoxy has flashed for best results, but definately in the epoxy's recoat window. Omni's 170 epoxy has a 3 day recoat window.