Re: ATM making a pitch lap

[Mark Cowan <cowanm@open.org>]

Richard Schwartz wrote:

> Uh, with all due respect, I tried this.  Result:  water got inside the
> plaster and caused the urethane to peel off.  Then the plaster started to
> crumble.  That is why I use dental stone for a foundation, and seal it with
> a mix of 5 parts turpentine to 1 part pitch, then cook it at 200 degrees F
> for a day or two before building the lap.

Boy that must smell good!!  Do you cook it outside???  :)

I had the same experience with plaster and gave it up.  Recently I've
used something called "Fix-All" from Custom Building Products with great
success.  It's a gypsum, starch, and wood flour composition; dries
really hard (trim it before it sets too much); expands (a little) when
it sets.  Get the big box, you'll need it eventually.  I seal it with
marine finish resin.  You can even get the pitch off again (chipping or
melting).

-Mark