Home Made Coil Dope AKA Q-Dope
 

Richard Knoppow wrote:

I have a half-pint mason jar that started with a third of MEK. I fed
it one and a half letter-sized inch-thick slabs of foam and it's
still not done.

I started with about half the jar filled with MEK. Since I used
styrofoam the displacement of the material before it dissolves is much
greater than after because so much of it is air. The first pieces
dissolved very quickly, in fact it looked like Alka-Seltzer
dissolving. Toward the end it took a few minutes for each additional
piece to dissolve. The total amount is amazing until you remember that
its mostly air. After the first flurry of very quick solution I added
pieces about twice a day and just let it alone between times. Of
course with the cap on, MEK will evaporate very quickly.

I stirred mine with a screwdriver and finished it in a couple nights.
Watching the first few chunks dissolve was rather amusing.

I don't know what sort of lid you used on the jar, but MEK softened up
the sealing compound. Based on what I found on a website on what sort
of gloves to use with MEK, I think butyl rubber caulk would be good to
keep the solvent from seeping out. Dissolve off the rest of the sealing
compound, then apply the caulk in its place. While you're waiting for
the caulk to cure, some foil on the jar should keep the MEK in place.
Or, even better, prepare the lid before mixing up the dope.


--
David Griffith
--- Put my last name where it belongs

Home Made Coil Dope AKA Q-Dope
 

"David Griffith" wrote in message
...
Richard Knoppow wrote:

I have a half-pint mason jar that started with a third
of MEK. I fed
it one and a half letter-sized inch-thick slabs of foam
and it's
still not done.

I started with about half the jar filled with MEK. Since
I used
styrofoam the displacement of the material before it
dissolves is much
greater than after because so much of it is air. The
first pieces
dissolved very quickly, in fact it looked like
Alka-Seltzer
dissolving. Toward the end it took a few minutes for each
additional
piece to dissolve. The total amount is amazing until you
remember that
its mostly air. After the first flurry of very quick
solution I added
pieces about twice a day and just let it alone between
times. Of
course with the cap on, MEK will evaporate very quickly.

I stirred mine with a screwdriver and finished it in a
couple nights.
Watching the first few chunks dissolve was rather amusing.

I don't know what sort of lid you used on the jar, but MEK
softened up
the sealing compound. Based on what I found on a website
on what sort
of gloves to use with MEK, I think butyl rubber caulk
would be good to
keep the solvent from seeping out. Dissolve off the rest
of the sealing
compound, then apply the caulk in its place. While you're
waiting for
the caulk to cure, some foil on the jar should keep the
MEK in place.
Or, even better, prepare the lid before mixing up the
dope.


--
David Griffith
--- Put my last name where it
belongs

Actually, I am not sure what the lid and gasket are
made of. This was a jar I bought at a local chemical supply
house that is now out of business (and sorely missed). I
tested both the cap and gasket with MEK before using the
jar, they seemed to be immune to it. Your suggestion about
using aluminum foil as a cap liner is a good one.
I just did a Google search for gloves suitable for use
with MEK and found a chart showing a variety of chemicals
and recommended gloves for use with them at:

http://msds.chem.ox.ac.uk/glovesbychemical.html

This lists teflon and butyl rubber as suitable for MEK.


--

--
Richard Knoppow
Los Angeles
WB6KBL