"CaveLamb" wrote in message
m...
Edward Hennessey wrote:
"anorton" wrote in message
...
"Usual suspect" wrote in message
...
This thing may actually may be use full for something. Presorvac
5
Cycle Marinater

http://woot.com/!
How about an epoxy mixer that doesn't add any bubbles to begin
with.
http://www.japanunix.co.jp/ju_en/pro...err_video.html

AN:

I followed your link. The machine looks pricey. Have you ever used
one?
I'm looking for something to "de-bubbelize" thickened and pigmented
polyester
resin.

Regards,

EH


Casting or laminating resin?

(sorry, hadn't been following closely)

--

Richard Lamb
email me:
web site: www.home.earthlink.net/~cavelamb


RL:

I'm using casting resin in a surface application to simulate shell in
fossil
restoration. Aside from the wax already in the polyester, thixotropic
powdered
glass is added so the material doesn't obey gravity in creeping off
the curvature
of the specimens. I usually add a single colored pigment or
composition of them
in the mix for a base color, catalyze that and pour it on the
specimen. If--and
that "if" occurs often--there is detailed color pattern in the
adjacent shell, I will
"paint" different pigment patterns into the pour before the catalyst
has a chance
to set. Once set, the repair gets sanded and polished. The difference
between
the shell and the original material can sometimes be very difficult to
discern when
all is done.

My problem appears to be the thixotropic material trapping air.
Bubbles form three
ways: in the mixing process; when air is trapped in specimen surface
irregularities on
resin application; and when additional colorant is daubed in once the
resin is in place.
The last wave of bubbles constitute the smallest number and, I think,
are probably
just something you have to understandably live with.

Glass works better than microballoons as a thickening agent but
because of the amount of
material necessary to keep the liquid from creeping off the rock, the
viscosity of the mix
prevents bubbles from easily migrating out.

A vaccuum pump and chamber recently arrived and next time out, they
will get a
trial. But other approaches and thoughts are always welcome.

Regards,

EH