A couple of years ago I put some 24k gold foil onto a flat piece of
wax, using double sided tape. I then used my milling machine to mill
out a large number of some fairly intricate patterns. I had done
this on a smaller scale before with no problem, using the tape to
hold down the gold to the wax. This time, maybe I waited too long
before attempting to peal the gold off the tape, but it is stuck on
now. Lat year I tried all kinds of solvents to remove the tape (often
for MONTHS at a time soaking!). Things i saw recommended on the
internet, like WD-40, goo gone, acetone, and pretty much any solvent
or corrosive chemical I could find in my shop. no dice. The solvent
can’t seem to get “behind” the tape to dissolve the adhesive. Due to
the fragile nature of the gold foil, i can’t use much force at all
in pealing off the tape. I am hoping there is something that would
just dissolve the tape (cellophane?) and the glue entirely.
Come onall you chemistry geniuses out there, what can I use?
Hi Todd,
Try lighter fluid (Naptha). That will get the adhesive, if it can
get at the adhesive.
Failing that, the concentrated orange cleaner stuff will eventually
dissolve the wax. Does a pretty good impersonation of Xylene, which
will really get the wax, if you can find it (and deal with it
safely.)
Given any thought to just melting the wax? Stick it in a tray at
250f or so, and melt the wax. Then pluck the gold/tape off the
surface. At that point, it should be easy to get the naptha to
interact with the tape. Of course, the gold may then be covered in
wax, causing a new problem, but it’s a thought.
FWIW,
Brian
Hi,
Would it be possible to hold your item over a candle or under a light
bulb for a few seconds to soften the adhesive? Or put into a freezer
and the tape should just “pop off”. I use cold to take my stones off
aluminum dop sticks when I use super glue. This is worth a try.
Veva
foil or leaf? If it’s foil and you’ve already tried solvents and it
didn’t lift any foil off and then let it sit again. I think off to
the refiner it would go when sending in your major refinery lot of
the year.
With magnification reverse the tape and using a tissue knife (brand
new and ultra sharp) try cutting through the tape backing width wise
If it lifts up gently roll it as far as it will go cleanly. No lift,
probably means a lost cause! If you used a double stick tape like a
"gorilla" brand, that expands it is a permanent bond- no hope of
retrieving it. If it’s a plastic (polyethylene or polyurethane based)
you may get a pyrex beaker of boiling water and submerge the piece of
tape, if there are any places that have separated you should see a
bubble where trapped hot air has helped identify the pockets where
whatever chemicals you used may have worked to loosen the foil from
backing. Although painstakingly tedious you can cut those bits away.
If it had not been subjected to a bunch of solvents previously, I
would say use the hot water method and where there are pockets inject
a very small amount of acetone or a brand like “goo off” and then put
a drop of cyanoacrylate to reseal the prick of the syringe and keep
the solvent contained. then once fully set, back into boiling water
and gently working the solvent down the strip. again. tedious. If it
can be scraped off with a bench knife there is another option that
may ruin the sheet form of the gold, but that can be remelted and
poured thinly over a carved depression in, say, cuttlefish bone, once
cooled, and quenched, rinse, anneal, then roll out as thin as
necessary in your mill. If not thin enough and between two thick oil
tanned leather leather squares or what have you, pound the gold
thinner (make certain you use the tanned side of the leather as
opposed to the rough inside!) with a dead blow mallet on a bench
block, or other large hard surface that keeps your hands far from the
work. To do this you must keep turning the sandwich and annealing
when it seems not to be spreading further. But be careful - use a
mesh on tripod to heat the thin metal or you will burn right through
it. Also under ordinary conditions using gold, you could wait to
pickle the piece until finished, but you want the piece as clean and
soft as possible as you progress to the desired thickness. Even a
tiny bit of flux glass will ruin the foil. If it’s really a leaf- the
refiner is the safest way to go as attempting to burn off the plastic
or even the less noxious cellophane, will be a nasty mess for a small
flake of gold that may require further work to separate it from the
mass.
After hurricane Katrina flooded my studio, house and world, a few
boxes of double weight gold leaf and a couple of packages of foil
were in a wooden safe box/cabinet bolted fairly high on a wall-.they
were ruined. I tried to reclaim the gold from the leaf by burning the
tissue off of five packs of sheets at a time- hoping to get most of
the maybe 16 gms.
from each 1000 sheets! The individual packets of sheets of leaf were
unopened. as were the foil wrappings. It was virtually useless- I
should have used Aqua regia and been assured it would have worked,
but it was a very expensive lesson and experiment. The foil was
returned and replaced (as though by miracle!). In the Orchid Archives
there is a very concisely written method by Nanz Aalund for
reclaiming gold. It’s definitely worth the read and save for future
reference… good luck. rer
Glues are sensitive to heat. That doesn’t mean break out the
torches. First try a hair dryer on high. If that is not enough you
can try a large watt light bulb not far above it. Last resort would
be a heat gun. They get up in the 500 degree F range. If you do use
the heat gun wear gloves. The adhesive will become very liquid at
higher temps. That should enable you to bull the gold sheet off.
The heat guns work wonders on all epoxies as well. Learned that when
i learned to make custom golf clubs for the hubby.
Aggie
If nothing else seems to work I would suggest you try on a test
piece to simply use a torch and do a controlled burn off of the tape
in a well ventilated space. Should do the trick.
I seem to find myself in sticky situations often, so this solvent is
always on the shelf: De-Solv-It. Available from Ace Hardware. It
comes in a 12 oz, clear plastic spray bottle (contents are yellow)
with a blue and white spay top. I’ve used all the others that you
mentioned, and sometimes they work, but so far this one is the
winner. Works on tar, crayon, asphaltum, wax, chewing gum in the
kids hair, you name it.
Mary