Spheres

In my attempt at shortening the production of various sized spheres (
1/4’’ - 1’’ ), I have placed an inner bezel in one half of the
sphere, which protrudes just slightly, thereby acting as step/guide in
aligning the other half prior to soldering. The model fits together
perfectly. I mold the two halfs and now reproduce them. The castings
fit together 95% acceptable. Now comes the soldering. No matter how
much solder I glob on to the seam and try to to flow it completely
around the seam I still have non-fills with subsequent pitting during
the polishing process. Everything is clean prior to soldering. Should
I sand every dome flat prior to soldering them together? I just
thought the inside bezel Idea would speed up the production process of
aligning the halves. In case I have not made myself clear in
describing the bezel- think of plastic Easter eggs which are able to
seperate. Any suggestions that might help me eliminate sanding my
fingers to the bone would be much appreciated.
Thanks, Peter Slone

Hi Peter, If these are to be drilled, you might try drilling at least
one side before soldering. The pressure from the expanding gas from
within the sphere will create an escape vent on your seam. A drill
hole should help. Will Estavillo, www.natureshop-gallery.com

hi…in your description it sounds as though you are casting 2
domes and perhaps as you describe the “95% acceptable”, this is were
you are loosing metal. i sand the bottoms of my domes to make
perfectly flat and align. you might need to compensate for shrinkage.
if you are contracting the casting, perhaps the waxes need closer
scrutiny.

questions and answers are difficult without seeing what we’re talking
about!

have a great day
carol

Hi Peter, I had this same problem, soooo what I did was rub the
spheres around on a knife sharpening stone. It worked really well
then I made the hole in both halves of the sphere and inserted a long
pin threw both holes and tightend it up and held them together with a
pair of hemastats then I fused them together… you kind of roll the
hemastats holding the bead around in the flame therefore heating it
all over the same (gosh I’m bad at explaining things) You could put
flux and solder on it instead of fusing. Hope this helps Susan
Chastain

Peter, You are so close so don’t despair. Keep what you have and
instead of solder, make a very thin washer to fit in between the two
halves of the plum material you are using and trim the excess with
snips. You then would fuse/weld/melt this material to combine the two
halves together and finish as normal. This will eliminate a high
percentage of the problems you are encountering with solder. If you
have a punch set then you could easily stamp out the size you need for
maintaining a good flow of washer parts for production.

Hope this helps.
Best Regards.
Neil George

Peter hello!

Working on those callouses on your finger tips it sounds like. If you
have any old inside ring sticks: they are sometimes handy for making
a holder. Just saw off the felt and make your impression in the wood.
Use bar soap or what-have you to create a little resistance if it
slides around to much in your depression.

You can order MX wheels for grinding. For your purpose, it sounds
like the medium, or the fine, would work well; and comparatively
quick. They also make split laps in MX. If you don’t have a split lap
machine you can mount on your polishing shaft with a 1/2" arbor, in
place of the tapered spindle.

If you want to make a split lap machine use an old washing machine
motor. They are meant to operate vertically. Just mount it kind of
like a steering wheel faces you in a car. The shroud is nothing
special; something a good sheet metal person can crank out for you in
less than an hour. I would guess $35 to $50. You should position a 3"
duct on the side for your collector to hook up too.

Don’t try the dryer motors for vertical use, they don’t last. Dryer
motors are great for polishing, however. The mounting plate attached
makes them quickly serviceable for jewelry polisher.
Tim

No matter how much solder I glob on to the seam and try to to flow
it completely around the seam I still have non-fills with
subsequent pitting during the polishing process.  

Peter -

Do you have a vent hole somewhere in your sphere? Otherwise the air
(and flux, and whatever else ) trapped inside will expand when heated
during soldering and will blow out, leaving holes in your seam. Try
cutting the inner bezel a tad thinner and roll some sheet solder down
until it just fills the space between the two halves and wrap a strip
of it all the way around the bezel. Fit the two halves together, flux
lightly, and pray silently while heating - it could work.

Mike

Dear Peter,

I’m sure there will be many responses to your request. It’s best to
probably try one at a time. If I were you I would probable try to
limit the amount of changes done. It DOES sound to me like you know
what your doing. I would look for some product concerns for you
difficulty. I also know soldering a sphere is damn near impossible if
you don’t vent it.

My comment would be to try a specific brand of solder. The brand is
Strern Clinton solder. I don’t use this solder much lately because it
has cadmium in it. It is however THE VERY BEST SOLDER I have ever
used. It pits the least of any solder I have ever used. My business
partner had cadmium poisoning in the late 70’s and very nearly died.
She had a closet workshop with no venting. She has a lot of reactions
to different smells now and can’t work at the bench. We work very
well together, she designs the jewelry and I product the jewelry.

The only other thing I might try is to use a paste solder and solder
the sphere is a handy melt furnace. This gives you a totally uniform
temperature rise and fall. Time consuming but maybe it might work.

Best Regards,
TR the Teacher & Student

Peter, I would not use the step bezel as I believe it will act as a
solder “sucker”, pulling the solder inside the seam. Instead, take a
pair of self closing soldering tweezers and form (bend) them into a
ball shape, just slightly smaller than the sphere to be soldered.
They cannot be too tight or the ball will collapse when soldering.
Just tight enough to hold the halves in alignment. Also I would
drill a very tiny hole in one of the spheres to allow gas to escape.
This can be soldered last, very quickly, or burnished over. (a very
tiny hole) Hope this helps John g

I have never tried soldering cast spheres, but I have soldered many
which I have dapped from sheet silver. After dapping them I make
sure the bottoms are flat by rubbing them on a piece of coarse emery
paper which I have tacked to a flat board. I then drill a small hole
in the exact center of each dome. In order to hold them
straight,while drilling, I place them on a wooden block in which I
have cut a small depression. I then lay the bottom half of the sphere
in a depression I have cut in my charcoal to keep the dome from
rolling around. Next, I flatten a length of wire solder in my
mill, and cut two pieces, each long enough to extend the entire
width of the opening of the dome, After fluxing the edges of the
domes and the solder strips, I lay the the solder strips across the
opening of the bottom half of the sphere. I then carefully align
the top half of the dome on the bottom half,.and heat with my
torch. The solder melts and completely flows around the dome making
a perfect seal . I tried snippets of solder placed around the edge
of the dome and never got a good seal, but the method I described
above in which I use strips of solder place across the opening has
worked every time. I hope this is helpful–Alma

Peter, Sanding the pieces flat is not a bad idea.If I get an
incomplete seam when soldering two pieces togethes I pickle the piece
well,clean it,sometimes running a saw blade in the gap will give you
two new surfaces for the solder to flow along and try soldering it
again.If you have a fairly large gap which the solder will never fill
roll out a sliver of silver if that is the metal you are working in
and stick the sliver into the gap ,solder and file.With silver it is
very hard to fill gaps with solder.Gold is a little easier but the
best approach I feel is to have the tightest fit possible.If you have
pits I use a rotory burnisher you can find them in most tool catalogs
or you can make them by bending and old shaft from a flex shaft tool
like a buffer or rubber wheel arbor into an “L” shape the tip of the
small leg of the L acts as a burnisher.Round it off and file and
buff.Lightly brush the area where the pits are and it will smear the
metal over the pits hit with a silicon blue wheel and buff taking care
not to reopen the pits at the buffer.You may be getting some varience
in your waxes when thay are being shot.I would try different mold
compounds to reduce shrinkage.Make sure there is no flexing of the
mold when shooting them so as not to distort the waxes in any way.Hope
this helps.Cast on dude. Best

J Morley

The idea of having a vent is very important. There must be a way for
the the expanding gases to get out. Probably the best thing to do
would be to make a pin-sized hole somewhere near the seam, but to
avoid soldering this spot right away. After the entire piece is
soldered (except for the pin hole) clean up the work to the polishing
stage. Then, go back and solder the hole shut, but use a solder with
a lower melting temperature. In this way you will only have to
wrestle one bubbling hole where you may need to glob it on a little.
Also, if you are making what are known as “fairy bells”, make the pin
hole in the location where the loop for the chain attaches so that
it’s soldering covers the hole.