Filler over filler

[yellowrallys]

Hey guys, when filling a repair, I always put on thin coats of filler instead of trying to fill the damage with one thick coat. So should each thin coat be sanded before applying the next, or can I keep adding layers without scuffing the previous coat?

[88GT]

sand each coat

[Len]

Hey guys, when filling a repair, I always put on thin coats of filler instead of trying to fill the damage with one thick coat. So should each thin coat be sanded before applying the next, or can I keep adding layers without scuffing the previous coat?

Yes, each coat needs to have the film removed that forms on top before the next layer is applied. It's usually best to apply your first couple of coats more heavily. Grind the metal the press your first pass of filler into the scratches and lay it on top more heavily. We usually use a cheese grater blade on the first thick layer while it's still soft, this eliminates a lot of sanding and levels the thick filler quickly. After cheese grating we sand the first layer a little then apply our second, allow to harden then sand, apply the third etc. etc. Each time we are applying another layer of filler we push that first pass into the surface then lay it on more heavily if needed.

As I get closer to the surface being right my filler and my coats become thinner. I start with Rage Gold and end with Rage Extreme which is more liquid and spreads more evenly. My final filler coat could end with the Extreme or I may apply a layer of Easy Sand and finish it with some 120 or 180 before I apply my 2K primer.