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Re: Epoxy: Wetting out with roller *LINK*
By:Rob Macks
Date: 12/28/2004, 11:14 am
In Response To: Epoxy: Wetting out with roller (Randy Ricchi)

: The thread below prompted me to ask about wetting out with a roller rather
: than squeegee-ing.

: I will be starting my first stripper this spring, and one of the things I've
: been thinking a lot about is how I will wet out the cloth.

: On Jim Kozel's website he mentions using a roller to wet out his cloth. He
: did a pre-coat beforehand, also with a roller.

: To my inexperienced mind, it seems like this would be a lot easier than
: pouring on the epoxy and then trying to spread it all around evenly
: without disturbing and/or floating the glass, or getting runs or sagging.

: Yet, it seems as though most people use the squeegee method.

: As long as you do a pre-coat, is it fairly easy to get proper saturation of
: the glass (6 oz)with a roller?

It's not just a matter of spreading the resin, but understanding how epoxy
and fiberglass cloth interact.

What you're trying to do is displace the air around the finely twisted fibers
of glass with a liquid that has a consistency of maple syrup at 70·.

Unless you use a special thin wet-out resin, that's the consistency of water
at room temperature, the resin will need a little time before it can displace
the air around the glass fibers.

A squeegee will force resin through the weave of glass. Unless the resin is very
thin, this force will generate a micro foam that will produce lighter colored areas
that may not be perceived on light colored woods but will show up on dark woods.
That is the best case scenario. The worst case scenario is milky clouds of micro foam
that can't be removed without removing the glass.

The resin must be thin and stay thin for a long period of time to allow the air around
the glass fibers to dissipate and rise to the surface.

Most people do not realize that epoxy starts thickening as soon as you mix in the
hardener. If you do not use all the strategies available to keep it thin, it will not
wet-out as well as it could. See my "Transparent Glass Lay-up" page below.

When wetting out cloth with a roller it's important to move onto the next area before
the glass looks transparent, allowing time for the resin to soak in.

West Systems make the only roller covers I will use.

If you have resin setting-up on your roller, you're mixing too big a batch,
or too fast a hardener.

I've built more than fifty boats. I have to be confident I'll have consistent
results for paying customers. I want totally transparent glass all over
with no silver fleck, which results from less than total wet-out.

For details on my wet-out method go to this page.

Messages In This Thread

Epoxy: Wetting out with roller
Randy Ricchi -- 12/27/2004, 12:53 pm
Specialized Rollers
vk1nf -- 12/28/2004, 9:38 pm
Re: Epoxy: Wetting out with roller *LINK*
Rob Macks -- 12/28/2004, 11:14 am
Re: Epoxy: Wetting out with roller
Randy Ricchi -- 12/28/2004, 1:51 pm
Re: Epoxy: Wetting out with roller
PatrickC -- 12/28/2004, 10:22 am
Re: Epoxy: Wetting out with roller
Chip Sandresky -- 12/27/2004, 10:00 pm
Re: Epoxy: Wetting out with roller
Robert N Pruden -- 12/28/2004, 12:48 am
Re: Epoxy: Wetting out with roller
Rod Tait, Orca Boats -- 12/27/2004, 2:04 pm
Squeegee vs. rollers
Robert N Pruden -- 12/28/2004, 12:41 am
Re: Epoxy: Wetting out with roller
Thomas Duncan -- 12/27/2004, 6:07 pm