another frame painting ?

painting my frame....i searched but no answers....when using por 15,chassis saver or chassis black.....when to use filler on pitting and small dings...before or after? do i paint then scuff the paint and fill the imperfections and paint again? or fill over bare metal and then paint? thanks sawbuck

 

Ive used Chassis Savor before. Its a single stage paint rust buster. POR-15 is not. Its a 3 stage i believe. Chassis Savor works great as long as your metal is clean. So if you plan on using bondo to smooth out your frame you"ll have to smooth it after the chassis savor dries. Has to be applied over bare metal.

 

P.S. Dont get it on your skin or good clothes. Took weeks for it to wear off my arms where it dripped over my gloves. Still on my work paints 4 years later.

 

POR-15 is really tough to get things to stick to. While it would be a good idea to use it to seal the chassis first, then fill imperfections, it isn't easy to do. You'd have to really sand the pits well, for the bondo to stick. And if it isn't scuffed deep in the pits, it may fall out when yousand it, because it didin't adhere well.
If the frame has been blasted, and it rust free, even inside the pits, I'd fill it first, then POR-15 or use another product over it. I've done this befire, and POR makes a great "primer" for a chassis, very tough and waterproof. You just need to topcoat it with either paint or POR's chassis paint. It breaks dwon in UV light, not that a chassis will see that, but it's good protection and looks good.
If painting over POR, put you paint on just when the POR gets tacky, not wet, not dry. If it dries, you need to recoat in 24 hours, or sand it well, or use POR's TieCoat to get paint to stick to it.
ANd no I don't work for POR-15, I've been using it for over 20 years. And personally I prefer Master Series Coatings version of this chemistry, but use them interchangeably.