How to make those pesky little granules stick: Granulation

Thanks for waiting, sorry for the delay. First a few points: I am not an
expert, but have been successful with my granulation, enough so that it is
acceptable and sellable in my galleries. Next, I took a seminar with Kent
Raible, very helpful and informative and I would recommend tht if you have
the opportunity…

Now: I use gum tragacanth powder mixed in distilled water. Kent suggests
that you add water untill the jelly-like mass dissolves. Let sit over night
until all clumps disolve. The mixture will be milky. THEN: to 1 part gum
solution, add 1 part battern’s flux and 3 parts distilled water. I coat my
18k piece with this solution, then pick up the granules (18k) with a fine
tipped brush dipped in the solution and place them on the piece. Let them
dry.

Once dry, I use a second solution (again from Kent). Add small amount of
copper carbonate powder to the above solution until you get a creamy
consistency. Then, take my small brush and dip in creamy, green solution and
lightly dab the tops of my granules until they suck up the solution. All
shuld be nicely coated, but not thick and gummy. Let dry.

The Hard part: I use oxy/propane torch with a reducing flame to fuse the
pieces together. I heat the brick well before fusing the piece, so that it
all heats evenly and you don’t have granular meltdown. Heating sequence:
piece turns black, black disappears, gold turns yellow, metal turns dull
red, metal turns orange red, then FLASHES. That’s it, another second and
meltdown. Once you see the flash you are done. Kent then reduces the flame
rapidly (get rid of oxygen), keeping it on the piece and quenches it in
water, this keeps the pretty shine. I try, but not that coordinated. Pickle
quickly, lightly, 18k turns greenish in too much pickle.

I work in 18k from David Fell, Kent makes his own alloy. His suggestion for
silver is: to use 835 silver for the granules and 925 silver for the
backing–do not use the copper carbonate. I have not done this, do not know.

Good luck, any other ??? please let me know.

Also, good table in Oppi Untrachts’s book on different granulation
techniques, and the Metals Technic Book by Tim McCreight has article on
silver granulation by John Cogswell. I highly recomment Tim’s book, all the
articles are wonderful, wll worth the investment.

Elizabeth
Elizabeth
T

Great stuff, Elizabeth!! Where do you get the gum traganth and copper
carbonate. Am I likely to find local sources, or should I look for
jewelry suppliers to carry them? Any thoughts on why you don’t use the
copper carbonate on silver… is it due to the difference in
copper/silver ratio between the sheet and the spheres that it’s not
required?

I’ll have to go review the section in Metals Technic

Someone (I forget…) once mentioned a clever idea for granulation:
carve a wax model and superglue tiny plastic spheres to it. After
casting, the result is supposed to look just like the real thing! He
had a source for the spheres (some kind of tiny ball bearing, I
believe). File that under “More Than One Way to Skin a Cat”. Not that
I condone cat skinning… :slight_smile:

Dave Sebaste

I got my gum traganth from a chemical supply house, they had to order as it
is not a fast moving item. Had to buy the smallest container.and that will
last 10 life times. Lloyd

Can I buy a couple lifetimes worth from you? :slight_smile:

Dave

Sorry about not including info. I got mine (gum trangacanth) and the copper
carbonate from Bryant Laboratory in Ca. 1101 Fifth St. Berkeley, CA 94710
(510) 526-3141.

Was able to get a small qty of gum for around $15, will still last a lifetime
though.

Send me your mailing address and I will send you some. Lloyd