I guidecoat a different way-
After the car's primed, and ready for sanding, I dust it with a
different color bomb-can primer. Or "guide coat black," which sands
easier! Then, the high spots sand free of guide coat quickly, while low
spots tend to be unsanded, and left guide-coated. Your sanding
technique is pretty critical, tho- if you don't block the panel pretty
carefully, it's easy to mislead yourself!
It's a good trick, and you can use it on bare metal, filler, and
fiberglass as well...
Also, some etch primers (PPG, Spies and Sikkens fer sher) are meant to
be a light misting- if you flow them on heavily, they actually weaken
the base layer. Apparently, while they provide excellent adhesion,
their film strength is pretty low...
William Hatfield wrote:
> Hello all: Guide coating is a process of using different colors of primer
> in a couple of coats so when you sand the high spots will show the other color
> brfore the low ones. In other words you will sand the top coat off the high
> spots first. hth Bill 66&67 spls in N.M.