metal to metal over primer??

[runningman]

Just got my K member back from acid dipping and e-coating.  I would like to fill some scratches and what not, it is e-coated with ppg epoxy primer.  Can I just use the metal to metal over that? 

[Doc74]

No, first rough it up with a grid 150 so it adheres. Metal to metal does best what it says, you can use another filler which would adhere better on epoxy but you'd still need to roughen it up a bit.
Just take a small piece of sanding paper and criss cross over the spots you want to fill, be sure to get the paint out of the scratches with a small screwdriver or something before you fill them and get all the dust out or the filler will float on it, till it cracks....

[runningman]

Okay thanks, is there any stronger filler than the metal to metal to use?  Just wondering how it would hold up on a k-member.  Just filing some small scratches and gouges though.  matt

[Doc74]

Yeah there's all sorts of liquid metals available but if you want it perfect then I suggest you weld it. Undeep scratches can be taken care of with a good grinder and then machine sanding it with less and less coarse paper to have a smooth surface and you can lay a nice weld on the deep ones and grind them smooth.That way it's all metal, no fillers so nothing there to crack or chip.
Personally I would weld and grind any imperfections and have the thing powdercoated. If you don't have a welder then properly clean the k-member and take it to a bodyshop or metalshop, some place with good welders. You can always just ask an employee if he wants to make a few bucks after hours.
Many people approach me with odd jobs like that, it's done in minutes, I make a few bucks and the customer saves a bunch, everyone happy !   

[sharpspike]

Yeah there's all sorts of liquid metals available but if you want it perfect then I suggest you weld it. Undeep scratches can be taken care of with a good grinder and then machine sanding it with less and less coarse paper to have a smooth surface and you can lay a nice weld on the deep ones and grind them smooth.That way it's all metal, no fillers so nothing there to crack or chip.
Personally I would weld and grind any imperfections and have the thing powdercoated. If you don't have a welder then properly clean the k-member and take it to a bodyshop or metalshop, some place with good welders. You can always just ask an employee if he wants to make a few bucks after hours.
Many people approach me with odd jobs like that, it's done in minutes, I make a few bucks and the customer saves a bunch, everyone happy !   

everyone is happy except the boss! ill talk to you tomorrow!

[runningman]

yeah I was thinking of doing that, I was just a little concerned about burning the epoxy primer that is between the metal that was applied during the e-coating process.  I may try to take it into work and have it tig welded to keep things a little cooler.  thanks   matt