Contrary to prior entry, 545 is a breeze to sand. One reason it used to be so popular. However, even the folks at Awlgrip will admit it was never intended to be a final coat. It is a base primer. Interprotect 2000 is another high quality primer that makes a great sanding base. If the object is to have a white final product, make the topcoat VC-underwater. And like Doug says, don't wait too long to sand it after the final coat. It goes rock hard. We always block VC-U down the morning after shooting the last coat.

There used to be a whole thread under "Bottom Paint", but can't seem to find it now. Too bad, lots of good information. We went through the process of debating what to do last winter, and ended up with Interlux VC Underwater Epoxy, sprayed on. The biggest advice was to not let it substantially setup prior to sanding, which we followed and didn't seem to have much of an issue. Also my spraying ability improved substantially by the final coat. We are in fresh water ~6 months, growth (slime) is a bit of a pain, requires weekly cleaning, but not much better on our neighbors anti-fouling bottom.

I am going to apply an epoxy bottom this winter. Still in the process of removing existing bottom paint and prepping the bottom for the epoxy. I am planning to use Awlgrip 545 on the bottom. A friend has suggested to me that: (i) rolling and tipping 545 will leave a fairly rough finish and (ii) the 545 can be very difficult to sand. If you have experience working with 545, I would apprciate learning your thoughts on its ease of application and sandability. In addition, if anyone has worked with both 545 and VC Epoxy with Teflon, I would be interested in learning the relative merits of both products. Thanks a lot.