For cleaning the pump parts I prefer lacquer thinner over acetone or
denatured alcohol.
It is the hardener side that need the cleaning, although cleaning the
clear resin side won't hurt, just messy. Don't forget to wear Nitrile
gloves.
http://www.wisegeek.com/what-are-nitrile-gloves.htm
Over time, the hardener builds up a thick black hard residue on the the
moving parts and they don't work correctly when used. Inside the tube
it builds up a coating, like arterial plaque, that reduces the flow and
skews the accuracy of the intended measure.
I have found that the dispensing tube for the hardener side may have to
be soaked longer after running a wire through them to remove any
hardened material. The only reason I would replace the unsightly
hardener reservoir would be if it was damaged in some way.
Make sure everything is clean, dry and moves freely when done. After
reassembling, do as Bob has mentioned, monitor your initial samples for
accuracy.
I have to clean my dispenser (and others) several times over the years
and have found that giving the hardener side parts a good soaking
overnight in lacquer thinner is best. LT does a better job than acetone
because it has slightly more aggressive chemical solvent properties
than acetone. Acetone has a higher evaporation rate and is not suitable
for overnight soaking, plus it is highly flammable.
http://www.artsparx.com/Undmatsolv.html
Having said all of that, acetone is used more for thinning hardener
than lacquer thiner and denatured alcohol. But because of the dangers
of acetone and alcohol I won't recommend them for cleaning. And as a
note, adding 5% of acetone or lacquer thinner to thin the
resin/hardener mix will reduce the epoxy's compressive strength by 35%
when cured so that is not a good thing in building structural items.
Now here is a tip: This method is great because you don't have to
disassemble and reassemble everything. Every 6 months disconnect the
resin side so it will not dispense anything when the handle is used.
Remove all the hardener you can because it can be reused after
cleaning. You should do this when the hardener side needs to be
refilled anyway and is low.
Place a cup full of lacquer thinner in the now nearly empty reservoir
and pump it through into another container. Replete the process several
times (over several hours) using the same original LT.
Use clean LT when near the end of that cleaning cycle. After every cup
full pump through, run a small wire far up the tube as possible to
loosen up whatever material you can and pump a few more cycles. This
harden hardener is difficult to remove completely with a quick attempt
at cleaning - it will take a better part of a day if you have not done
regular cleaning.
Use a new cup full of LT for the overnight soaking. Pump enough through
to be sure the tube is filled, plugged and let it sit overnight. Common
sense will tell you if the mechanism is clean.
FWIW.
Warm regards,
Gary
Fort Lauderdale Executive
http://www.uslan.com/hinge-kit.html
Unscrew each
nozzle, there is a check
valve ball and spring underneath. I soaked them in acetone and
replaced. Then, after reassembly I pumped acetone thru the pump (got
out
some sticky black stuff). Finally I replaced the reservoirs. Works
great now. Don’t forget to weigh a couple of pumps to make sure it
is dispensing the correct ratio. Throw this initial test batch away in
case it is contaminated with acetone. I don’t think acetone will
affect the reservoirs, unless they have changed the material.
Bob
Lancair 56SH
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