On Apr 8, 2:36*am, lemel_man wrote:
On 08/04/2012 07:21, Ivan Vegvary wrote:







Wife has a gold puzzle ring that is too large for her finger. *(Puzzle
rings are four concentric bands that come together showing a pattern
on top of the finger).

Her jeweler wants $150 to re-size the rings. *Not going to spend that
kind of money. *My wife says she would be more than happy with a
dollop of solder on the bottom inside of the ring to make it smaller.
Of course at the same time it would hold the four bands together
obviating their falling apart. *This could all be done by wrapping
dental floss or tape, but not very elegant.

I was hoping to lay a bead of solder on the inside bottom and then
file/sand it down to a smooth circular arc.

Questions: *Can this be done? *Is it non-destructive and reversible?
Can gold be soldered easily? *Do I use a flux? *etc. etc.

Thanks for all suggestions and replies.

Ivan Vegvary

I'm a working goldsmith (which some people might have deduced from my
username) and, amongst other things, I hand-make puzzle rings in all
precious metals. If you were in the UK then I could re-size the ring for
a lot less than $150, but I assume you're not.

The most important "no-no" is "NEVER USE LEAD SOLDER ON JEWELLERY". Lead
solder is nowhere near strong enough, and sooner or later the joint will
break and, to make a proper joint with gold solder, *every* scrap of
lead solder must first be removed. If it isn't, then the temperatures
required for gold solder will cause the lead solder to eat into the
gold, rather like mercury does. This will totally ruin the job.

Gold is soldered with gold solder in a process exactly like silver
soldering (silver brazing). Gold solder is an alloy of gold with a
purity that, in the UK at least, matches the alloy to be soldered. ie.
14K gold is soldered with 14K gold that has a lower melting point than
normal 14K gold. The melting point is, typically, around 600-700C.
You can use a normal silver-solder flux, or you can get a special flux
formulated for precious metals. The special flux can be used straight
out of the container - no mixing, saves time.

If you have previous experience with silver soldering, then gold
soldering should present few difficulties, but soldering rings presents
certain unique problems. The first being that most rings have at least
one soldered joint and, unless you are very careful, the previous joint
will spring apart when you attempt another one. For an experienced
jeweller this is nuisance, but for a novice this is a show stopper. The
second is, rings are rather small bits of metal and it is *very* easy to
melt the entire ring when attempting to solder a joint. Unless you've
done it before, I would advise you to practise a lot before working on
anything you value.

The final section is about tidying up afterwards. I would certainly not
recommend adding beads or blobs of gold in an attempt to make a ring
smaller. Do the job properly. Cut a piece out and solder the joint.
After soldering, the first thing you notice is that the ring has gone
black, or very discoloured. This is oxide, which must be removed by
acid. You then notice that the ring is no longer round, so you must have
some method of truing it up. A jeweller will use a ring mandrel, but the
chances are that you don't have one. After making the ring round again
you will notice that it's no longer shiny, so you will have to polish
it, but this should not present any difficulties to somebody who has any
experience with metal.

The proper gold solder will not be cheap, but the actual job itself
shouldn't be beyond the capabilities of any competent metal worker. But
first practise on something you don't mind messing up.
IHTH

--
Regards, Gary Wooding
(To reply by email, change gug to goog in my address)

Wow! What a thorough and thoughtful reply. I thought I could simply
take my electric soldering iron and finish the job in less than 5
minutes.

Method described is probably way beyond my skill level. Since 4
bands would need to be cut, soldered, sized and then polished, I can
see why they want to charge so much to do this job. Will definitely
go with the 'ring sizer' solution described by Gunner, below.

Thank you so much, not just for the advice, but what I have learned
about the process.

Ivan Vegvary