No, the peaks and pimple-tops from the previous 'roll coat' set the depth, the trowel 'rides' on top of the previous peaks. Usually takes 2-3 trowel applications to get the barrier smooth. You dont want to knock-down the first/previous 'pimples' with a trowel as they set the height for the trowel to fill. If you find that youre not 'thick enough' add another 'roll coat' and let partly cure.
You can apply bottom paint in the same way ... and you get a smoothness equivalent to 'almost as smooth as a babies ass'. Smooth surfaces have less adhesion for 'growth' ... and 'release' faster and more completely when at speed - less 'roughness' for the crap to 'stick to'. With smooth applied ablatives you also get longer life as the 'total' surface area exposed is at a minimum - somewhat important if you seen the latest prices for ablatives.
Last edited by RichH; 02-09-2011 at 12:34 PM.