Back to Ganoksin | FAQ | Contact

Bezel Melting Problems


#1

Lately I have been having lots of problems accidentally melting
sterling silver bezel when trying to solder it to a sterling silver
pendant base. I make my bezel out of 0.3 mm sterling silver. I use a
little torch oxy/propane set up. Today I was using a number six tip,
but have had the problem when using other tips as well. I usually run
a reducing flame ie not enough oxygen. I have been doing this because
a nice balanced flame seems too hot. I heat the base and the bezel
from the top. I use pripps flux and medium solder. I try not to heat
the bezel directly. The bezel seems to melt just as the solder
liquefies. And then I find that the solder hasn’t taken and the bezel
did not stick to the pendant base.

My next attempt will be to heat from the bottom using a steel mesh
on a tripod, but that will be tomorrow as it is getting a bit too
late at night for me.

Anyone have any suggestions for tomorrow’s attempts?

Thanks
Milt Fischbein
Calgary Alberta Canada


#2

Hi Milt, Try heating the base only and avoid any direct heat to the
bezel until you see your solder is ready to flow. Solder always flows
towards the heat. Let the larger piece take the solder. You cannot
just melt the solder and hope it will bond…that only happens when
you don’t want it to…grin.

Also I would suggest getting used to a hotter flame. It will
actually give you more control. Master the flame and be observant of
the material’s color changes while under heat.

I hope that helps,
Mark


#3

Hi, Milt- I use a tripod for this. I heat from the bottom until the
piece nears soldering temperature, then bring the flame to the top
to draw the solder around the bezel. It works great.

Lee Einer


#4

Dear Milt, Are you sure you are not using IT solder? It is usually
used only for soldering when an item is subsequently going to be enameled.


#5

Milt, Try propping the steel mesh up on three blocks of charcoal, in
a U shape. This will help to contain the heat. Definitely heat from
below. I would use a neutral flame.

Joel Schwalb
@Joel_Schwalb
www.schwalbstudio.com


#6

Milt, You can do several thing to correct your problem. First, you
should be sure the join is well fluxed. I don’t know what kind of
flux you are using…I normally use Battern’s. I had a situation
recently where I was using some very old Battern’s (the clear kind)
and could not get a good join…tried three times in my usual method.
Got some good fresh (and new) flux and it soldered perfectly. This
has been discussed previously and, while I don’t remember any
agreement on whether old flux looses its action, this is an example
of what may happen.

Second, heat control is very important while soldering bezels and
backs. A Nr 6 tip should do the trip up to at least 22x30mm but
over that you either have to get a multi-oriface tip (also used for
casting with the little torch) or switch to acelytene. It is
difficult to solder bezels/backs of any size from the top with the
LT. It should be heated from the back. If you use a large heavy
wire mat it will take most of the heat away and, because you have to
keep the item heated longer, it will oxidize and not solder. You
must get in with the most heat fast and get out again.

Try this instead…get everything ready to solder (make sure it is a
good flat fit), the back plate should extend out from the bezel 4 or
5 mm. Now pick up the bezel/plate with a pair of medium tweezers and
hold it flat in front of you. Bring the tip of the torch flame up to
the underside and move it in circles until you see dull red. Now
concentrate the flame under the bezel in the area furtherst from the
tweezers. The solder (snippets should be on the inside of the bezel)
will melt and flow. Move the flame around to each side until each
snippet flows. At this point, stop, lay the bezel down and quickly
pick up the other end with the tweezers. Heat again and solder the
remaining area. With practice, you can do this without switching
ends. In this way, all the heat goes into the piece being soldered
and the LT will work on pieces up to 30x40!

Cheers, Don at the Charles Belle Studio in SOFL where simple
elegance IS fine jewelry! @coralnut2


#7
 Anyone have any suggestions for tomorrow's attempts? 

As you’ve probably already surmised, you’re getting the bezels too
hot, whilst the base doesn’t get hot enough. That’s the big problem
with heating from the top, since the bezel is a lot lighter than the
base, AND the base is getting heat from just one side. Plus, with a
small flame like the little torch, heating both parts gets even
trickier.

The mesh can work. But a method I like a little better is to put a
few nails or cotter pins (which are nicer since they don’t roll once
you’ve spread the legs apart a bit) on a charcoal block and put your
base sheet on those. That creates an air space between the block and
the sheet, which does two things. First, it reduces the heat sink
effect of the block, so it’s easier to get the base sheet hot. And,
in heating you direct the flame at the lower edge of the base sheet,
towards that air space. The flame gasses thus travel easily under
the base sheet, heating from below. In practice, you’re flame is
still coming from the top. You’re moving the torch fairly rapidly,
perhaps in a circular motion, over most of the base sheet, around but
not directly at the bezel itself, but also outside the edges of the
base sheet at the block just next to it’s edge. That’s when the flame
gets to spread under the sheet. By balancing how much of the time is
spent heating from below in this manner, with how much time is spent
heating the top and bezel, you’ll have better control with heating
both parts evenly.

You might also try reducing the ambient lighting, so the
temperatures might be easier to judge. Silver does glow before it
melts. Also, have enough flux on the base sheet,so that there are at
least some areas where a bit of flux is heated just by the base, not
the joint between the base and bezel. the melting flux is also a
temperature indicator, so if that area of flux isn’t molten, but the
flux next to the bezel is, then you know your heat isn’t even.

Hope that helps.
Peter


#8

You will probably get a lot of tips on other ways to do this.
Here’s what works for me…

I always leave excess sterling on the base piece so I have a place
on which to hold the base with some locking tweezers which are
hanging off the edge of my bench (therefore no tripod or steel mesh
is required to hold it). This allows me to completely access the top
and bottom of the piece with my flame. I use 26 gauge fine silver
for my bezels and always heat them from the back/bottom (non-bezel
side), usually attaching them to the base with medium solder. If the
piece is to have a bale or pin on the back of the base, I will then
flip the piece over (with the bezel toward the ground) and then
solder the findings to the back applying the flame to the non-bezel
side of the piece. I have yet to melt a bezel. Since the weight of
the piece is being held in the tweezers, be careful to not overheat
things or the weight of the piece can cause the back to distort or
droop when it reaches temperature.

Good luck!
Elizabeth
www.borntobeworn.com


#9

Dear Milt i have had the same problem, and I solved it by heating
from underneath but then had a problem with the piece melting to the
screen solved that by heating the piece from underneath while it
sits on a piece of stainless steel I use to roll out metal on ( I
have several dozen blanks ) any way teh technique is as follows rest
piece on the blank on your screen heat from underneath till the
solder turns shinny ( just before it flows ) when that happens
quickly bring your flame up to the top of the piece aiming the tip
of the flame at the BASE of the bezel to draw the solder through the
joint…since I started using this technique I have not melted a
bezel not even the serated edge ones and they used to give me fits
HTH Ron


#10

Hi Milt,

     Lately I have been having lots of problems accidentally
melting sterling silver bezel when trying to solder it to a
sterling silver pendant base. Anyone have any suggestions for
tomorrow's attempts? 

If I were you, I’d use fine silver bezel wire. It has a higher
melting point than sterling. It’s also much easier to push over the
stone & holds very well. I’ve never lost a stone due to the fine
silver bezel.

Dave


#11
    Lately I have been having lots of problems accidentally
melting sterling silver bezel when trying to solder it to a
sterling silver pendant base...I use a little torch oxy/propane set
up. Today I was using a number six tip, but have had the problem
when using other tips as well. 

A #6 tip is overkill. Use a #4. Use a #3 if the pendant base plate
is particularly light, 24-30 ga. Your flame should have three
distinct zones in dim light. A bright blue inner cone, followed by a
yellow cone in the middle, followed by an outer cone of blue/green.
Aim for the area between the inner and middle cone to touch the
metal, as this is the most efficient heat concentration.

    I use pripps flux and medium solder. 

Pripps is an effective firescale inhibitor, but you need to use an
additional flux. Try Batterns or Handi-Flux in addition to your
Pripps.

    ...I heat the base and the bezel from the top.  I try not to
heat the bezel directly. The bezel seems to melt just as the solder
liquefies. 

With silver, remember your whole piece has to be up to a consistent
heat level. It radiates heat like crazy. Concentrate your flame on
the base plate as you have been doing, both around the outside of the
bezel and the inside of the bezel, but not on the bezel itself. It’s
thinner gauge material and melts more easily than your heavier base
plate.

Remember these things also:

If your solder balls, you have surface contamination. Make sure your
metals are free of tarnish, oil and dirt.

Make sure your joining surfaces are flat. Solder cannot jump a gap.
File both the bottom of the bezel, and make sure your base plate is
level and hasn’t been distorted by heat expansion.

If your solder has pits, you’ve overheated it. Cut back on your
oxygen, or make sure you’re heating away from the join, concentrating
on preheating the heavier base plate first.

If you flux looks brownish or blackish, you have contaminated your
piece with soot. Cut back on the gas.

If solder is clumpy, you have either underheated or used too much
solder.

Are you getting a draft? A draught of cool air across your piece can
often draw away enough heat to affect your soldering.

Make sure your solder is really solder. This is something that
happens even to old pros. Occasionally we pick up a piece of wire or
sheet we think is solder, and it’s actually a metal masquerading as
solder. Groan! The first thing I do when I get my solder in is to
mark it. Sheet solder is marked all over on both sides with a sharp
awl with the type and color. Example: #75, #70, 14kyh (14 kt. yellow
hard), 14kym, 18ky, 14kr. Chips are put in film canister tops on my
bench (keeps them contained and can find it easily), and when I’m
done with it, the extra chips go in the film canister itself, which
is marked with the type in enamel pen. Wire solder is kinked on one
end of the coil, and the piece I cut off, to let me know which temp
it is: a square for extra hard, a double kink for hard, single kink
for medium, circle for easy.

And finally, find a pro, whether jeweler or rockhound, whine and
wheedle your way into sitting in while they’re working. Observe.

Good luck. From an old hand who learned the hard way, and found out
it’s a lot simpler to learn from someone who knows what they’re doing.


#12

Milt, Heating from the bottom should solve your problem, although
I’ve never really liked soldering through a screen.The screen
absorbs too much heat. One solution is to hold the base plate in a
third hand, or if there is no way to get a grip on it, to place it
on two parallel wires (titanium bicycle spokes) suspended between a
couple of charcoal blocks. You can also bend a piece of heavy wire
into a paddle shape , grip that in a vise, and set the piece on
that. Other than that of course you must make sure the metal is
clean, as well as the solder, and well fluxed. Hope this helps.

Jerry in Kodiak


#13

I always heat my bezel backing from the back until solder is nearly
ready to flow and then I draw the bead all the way around from the
top at the join of the backing/bezel.

J. S. Ellington


#14
...put a few nails or cotter pins on a charcoal block and put your
base sheet on those.  That creates an air space between the block
and the sheet, which does two things.  First, it reduces the heat
sink effect of the block, so it's easier to get the base sheet hot. 

I have to question this, Peter, though I can’t remember the last
time you were wrong on a technical matter :-). Charcoal blocks get
very hot and because they are a poor conductor of heat, the heat
doesn’t spread out; it stays close to the heat source and reflects
back to the piece being soldered. So rather than acting as a heat
sink, charcoal blocks serve to facilitate the soldering process
(unlike most refractory materials).

To take advantage of this characteristic when soldering bezels, I
move my torch around and around the outside of the bezel,
deliberately heating the block. With a big enough and hot enough
flame, it is possible to flow all of the solder at once without ever
actually heating the metal directly. Unless the bezel is especially
large or the metal unusually thick, this should work every time. I
have a feeling, Milt, that you need to use more heat, possibly with a
larger torch tip (depending on the size of the piece) and never point
the flame directly at the bezel wire. Beth


#15

Hi, Sounds like a top heating problem to me…directing the heat
directly at the bezel instead of heating the base up first, and I
have to agree with another replier that fine silver bezel strip is
much better for this work than sterling. I always try to get the
whole piece off the surface of the soldering block somehow before
starting to heat, as you can then get the flame under the base/bezel
backplate of the piece before getting anywhere near to the bezel
itself, and thus the bezel starts to heat up gently by conduction
from the baseplate rather than getting the full frontal blast from
the torch. I use either a third hand or rest the whole piece on top
of a piece of scrap strip folded into a two thirds circle shape.
Steve Holden in sunny Ibiza!

www.platayflores.com


#16

When soldering bezels to a plate I heat from the side opposite the
bezel.

I set two fire bricks on a large solder pad. I leave a gap between
the fire bricks slightly narrower than the plate. I set the edges
of the plate on the fire bricks so that the bottom of the plate is
exposed. I set the bricks slightly over the edge of a large solder
pad. This allows me to direct the torch vertically against the
plate. I mark the bezel side of the plate with a sharpie pen. When
heating, the mark will start to disappear when medium solder temp is
reached. At this point I play the flame on the bezel side of the
plate.

If the plate is very thin I move the bricks closer together but
leave enough gap for the flame to hit the bottom of the plate.

I use a large torch tip and heat the metal as rapidly as possible.

Don’t forget to coat all surfaces with an anti-firescale flux before
each solder step.

If you need a better description contact me directly and I will make
up a sketch.

Lee Epperson


#17
   I have to question this, Peter, though I can't remember the
last time you were wrong on a technical matter :-).  Charcoal
blocks get very hot and because they are a poor conductor of heat,
the heat doesn't spread out; it stays close to the heat source and
reflects back to the piece being soldered.  So rather than acting
as a heat sink, charcoal blocks serve to facilitate the soldering
process (unlike most refractory materials). 

The charcoal blocks not only reflect the heat well, back to the
metal, but any extra oxygen gets used in actually burning the
charcoal, making the environment around the metal nicely reducing, so
things stay cleaner, and in doing that, additional heat is also
generated by the burning charcoal. So yes, the charcoal blocks can
considerably facilitate the process, as you say. But for that to
happen, the block has to be reached by the flame. If the sheet
metal is sitting right on the block, the area it’s sitting on will be
heated only by the metal, which, though not much, chills the metal,
and won’t cause actual combustion of the block. Now, certainly as
the block warms up, it then radiates this heat back to the metal, and
doesn’t cool the metal much. But you get better heating if you lift
the metal slightly above the block, so the flame can get underneath
the metal. Then the heat from the flame which heats the block
reflects well into the metal, as well as the flame also heating the
metal from below. Try it and compare. For small pieces, it’s not a
big difference, but as the surface area of the piece your soldering
on gets larger, it gets quite noticeable. One alternative to using
nails or cotter pins that also works is just to cut some grooves in
the surface of the block, again so that the flame can get underneath
a bit. And after a block has been used for a while, it’s surface
gets pitted and rough enough that even without the grooves, you get
some air space, so then it also works this way.

Peter


#18
   A #6 tip is overkill. Use a #4. Use a #3 if the pendant base
plate is particularly light, 24-30 ga. 

With oxygen and PROPANE or natural gas, I think a number six tip
isn’t unreasonable. With acetylene, you’re right, it’s perhaps
overkill. But a #4 is pretty small with propane, and getting a #3 to
even light, and stay lit, with propane, can be a good trick in itself
sometimes. With oxy/acetylene, of course, it’s just fine. but with
propane, about all you’ll solder with a #3 is small wire work… Of
course, all this depends as well on the size bezel being soldered. If
it’s a 3mm bezel going onto thin sheet, that’s a whole different
problem that if it’s an 18x13 bezel…

Peter


#19

this works! paint the top edge of the bezel with “liquid paper for
copiers” use ONLY the formula for copiers in the red botttle…the
regular formula iin the black bottle has more dangerous fumes. Dry
it before you apply flux so they don’t mix. Also works for protecting
other small parts when soldering to larger/heavier parts. Marianne
Hunter


#20

Thanks to everyone who replied to my post about melting bezels.

I first tried heating the pendant from below on one of those tripods
with a steel screen. As many of you suggested, the tripod and screen
acted like a heat sink and I could not get the solder to flow.

Next I tried the third hand method and heated from below again.
Worked great. The solder flowed very well and the bezel did not melt.

Regards
Milt Fischbein