If you're sandblasting the rust completely, you won't need to use POR15. Use a good self-etching primer that's made to adhere to bare metal. Be careful when using it, the fumes are noxious, so better to do it outside. Only use a self-etching primer. Then you can paint the frame or whatever you're doing. A lot of people are using Herculiner on their frames nowadays. Looks good and if done correctly, will last longer than you.
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Americans sleep safely in their beds because rough men stand ready in the night to visit violence on those who would do them harm...
Happiness is a Barrett M82A1 .50 caliber and a target at least a click out........
I come in peace. I didn't bring artillery. But I'm pleading with you with tears in my eyes, if you f**k with me, I'll kill you all.....