Strip disc - Southern Polyurethanes Forum

Do ya'll think the strip discs, the fabric ones that go on a die grinder or drill, provide a proper surface for epoxy primer adhesion?
The surface appears to almost be polished after use, sort of like with a wire brush.

I had a '55 Chevy trunk lid media blasted (plastic) on the underside to remove 3 layers of paint. The plastic leaves a smooth finish that has to
be sanded. I have been hand sanding every nook and cranny (80 grit) and it is going to take a VERY long time, more than I can account to my
customer for. Was wondering if the strip disc would would be an option to speed things up and be able to go straight to epoxy after clean-up.
Thanks Have you considered going to a different sandblast media to give bite to the primer? Aluminum oxide at low pressure will get into the corners and give you plenty of cross hatch. Being on the military side of painting there are different primers for different applications, most of mine need to be applied over anodize or chromate, so I find the primer that meets specifications for being used over those smooth surfaces. I can see the areas you are concerned with and know its pretty impossible to mechanically find a way to get bite there.

crashtech; said: I have experienced poor adhesion of some materials when applying over bare metal finishes left behind by certain clean n strip discs. When in doubt, at least scuff sand or lightly sandblast any metal that has a polished or too shiny look to it.

Crash, the 3M discs have worked good for me for years but if you want one that leaves a more aggressive scratch Norton Beartex works good and lasts 3X longer than the 3M black discs. I've tried the 3M purple and not a big fan-too stiff. One thing to remember with the original 3M version is if it's spun too fast the heat will leave a clear coating that most wax and grease removers won't take off, it'll even affect welding. I run them kinda slow and that also makes for a more aggressive texture.

Bob Hollinshead; said: Crash, the 3M discs have worked good for me for years but if you want one that leaves a more aggressive scratch Norton Beartex works good and lasts 3X longer than the 3M black discs. I've tried the 3M purple and not a big fan-too stiff.

I remember Beartex from a deburring shop I worked at as a kid. Will have to try that, thanks. I don't like the purple "Imperial" wheels either.

One thing to remember with the original 3M version is if it's spun too fast the heat will leave a clear coating that most wax and grease removers won't take off, it'll even affect welding. I run them kinda slow and that also makes for a more aggressive texture.

Yes, I have seen that effect before and it's the main reason for my advice. My thinking is that it's always at risk for being present even if we think that a slow enough speed has been used, so it's always best to go back over the finish left by such discs, especially when a less experienced hand is at the controls... jmho.