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Roger Derby
 
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I bought one of the "propeller on the end of a stalk," Stainless Steel,
gadgets designed for use in a variable speed electric drill. (I suspect
very slow is the proper setting, based on kitchen mixer experience.) I
haven't mixed a big enough batch yet to justify cleaning it afterward, but
you might experiment with some of the cheap (disposable) equivalents sold
for mixing paint.

Digging thru the "Goo Grinder" web site I found a price of $297 USD for the
smallest which tallies with the "Type A Pump" that System Three used to sell
for $300. A friend had one for use in building his experimental aircraft,
and for that kind of job it seemed to pay off. Rather a different
application than coating plywood.

Roger

http://home.earthlink.net/~derbyrm

"DSK" wrote in message
.. .
Jim Conlin wrote:
Measuring epoxy is a pain. The mustard pumps are fine if you need 1 to 8
oz. (30 ml. to 200 ml.), but if you need a quart, they're a PITA.
Weighing is hard to do with the level of repeatable precision that i'd
like. There's no practical and reliable way to precisely measure a small
(5ml.) batch.
There are also commercial epoxy measuring pumps, the "Sticky Stuff
Dispenser" and "Goo Grinder" from These folks
http://www.michaelengineering.com/ which look like a good start, but
seem overpriced to me. I'm envisioning perhaps a pair of gear pumps,
geared tpogether at 5:1 or whatever. They could be operated by a hand
crank or spun with something powered.
So, my question is this- Who can recommend a positive displacement
rotary pump that is inexpensive and will tolerate the nasty chemicals of
epoxy, hardeners and solvents?


http://www1.mscdirect.com/CGI/NNLMK3...07854&PMPROD=9

I suspect a set-up based on industrial metering pumps would be more
expensive than a "Goo-Grinder" (they say 'call for price' which always
****es me off... is it some big secret?) unless you could find a couple on
E-Bay. There are several models that have built in digital controllers,
you could punch in any ratio you want and it would be very precise.
Another possible key word to try is "injection pump" although sometimes
this means a venturi type.

It is a real PITA to mix larger batches of epoxy but the real slow down
I'm experiencing is mixing in the fillers. I've been experimenting with
bond strength with micro fibers and they really do help a lot. It's
surprising the difference in rigidity between a panel laid up with
microfibers & one with straight resin. But it's slow & nasty to mix. Any
advice on this one?

Fresh Breezes- Doug King