As far as I've read, the Slick Sand has less potential to shrink so you do not see sanding scratches down the road. It also goes on ultra thick, high build. The better your bodywork is, the less build you will need. Some on here use only epoxy, that way you'll always have great adhesion and no shrink risk. Others use epoxy, then 2k. Others yet use epoxy then slick sand.
My take is that using slick sand to cover poor bodywork may work, but isn't ideal or the "right way". I'm going to try it someday when blocking a car out to try and get it laser straight, maybe I'll have a better answer then.
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As far as I've read, the Slick Sand has less potential to shrink so you do not see sanding scratches down the road. It also goes on ultra thick, high build. The better your bodywork is, the less build you will need. Some on here use only epoxy, that way you'll always have great adhesion and no shrink risk. Others use epoxy, then 2k. Others yet use epoxy then slick sand.
My take is that using slick sand to cover poor bodywork may work, but isn't ideal or the "right way". I'm going to try it someday when blocking a car out to try and get it laser straight, maybe I'll have a better answer then.