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Soldering hollow forms


#1

I have a question regarding soldering. I’ve been taught when
soldering hollow forms you should always have a hole in your piece
to let the heat escape. In the 10/02 issue of Lapidary Journal Bead
Annual it mentions in the article “Hollow Silver Bead” to solder the
two discs together (w/o hole). Isn’t that dangerous? Could someone
please enlighten me?

Janice


#2

I read the same article and agree with your concern. The author
apparently is soldering a closed hollow to prevent pickle acid from
entering the piece. Instead, the author could have drilled at least
one of the two holes (drilled after soldering), and used a
needle-tip flux dispenser bottle to force water and baking soda in
to neutralize and wash out the acid. Maybe this works for the
author but I worry that a reader might decide to reheat the closed
form to solder a jump ring or some other second solder which would
set up a very dangerous situation.

I have received several comments from Orchid readers regarding the
Short-Course for making silver beads on my web site
(www.psi-design.com) because I recommend drilling air/bead holes
before doming and well before soldering. In my book I go into more
detail about the dangers of soldering a closed hollow form.

This is not the first article run by Lapidary Journal that showcases
soldering a closed hollow form without an air hole. Where are the
editors? Nancy


#3

Janice When you are soldering a hollow sphere together you can do so
without a hole IF it is the last soldering you will do. Draw the
solder along and once it has sealed, take the heat off it. I am
assuming the hollow bead was constructed and then drilled out later
for use as a bead. If you are making the sphere and then soldering
it to something else you need the hole to allow for the expansion.
When I learned this it stuck in my mind because my instructor
explained the principle and then shared the story of how as an
apprentice he had worked on a ring that he did not know was hollow
and when he heated it, it exploded and embedded bits of gold in his
face. Not to try and horrify people but it did re-enforce the need
to be aware of the process and be aware of planning the steps
involved in the work.

Brigid Ryder


#4
    I have a question regarding soldering.  I've been taught when
soldering hollow forms you should always have a hole in your piece
to let the heat escape. 

Janice, It does sound confusing, but the simple 'trick is: The
first time you solder something ‘sealed’ together, like a 2 part
bead, a tube earring etc, you are sealing in air for the first time.
But you must not linger at that last solder…solder it closed and
take the heat off. The danger lies in soldering an already sealed
item, as the air inside will expand with the heat and must have a
small hole drilled somewhere inconspicuous (to be sealed safely[if
you want]AFTER the work is done)

I just finished taking_Jewelers of America Certified Bench Jeweler
course…some of the jobs took some concentration, but one was very
easy, IF, you knew about drilling a air release hole, tricky if you
didn’t… It was a pair of sealed half dome earring to have post
soldered to. Therefore, you had to drill a hole at he bottom, solder
post, and seal hole to finish piece. the last solder seals the air
but by doing it quickly…doesn’t heat up enough to expand.

25 years ago I didn’t know this and was soldering a broken post back
on a sealed ster. silver hoop e/r. I was leaning close when the e/r
exploded! with ,what sounded louder than a firecracker. Ripping the
seam on the e/r and ruining it. My eardrums were not the same for a
week!_ Thomas Blair


#5

In small pieces, say under 1/2", if the metal gauge is thick enough
you can get away with soldering two hollow forms together without a
hole. The danger comes if you reheat the item without piercing it.
Implosion as it’s cooled versus explosion as it’s heated.

Tony Konrath
Gold and Stone
http://www.goldandstone.com


#6

If you are very skilled and have done lots and lots of soldering then
you could probably get away with not leaving holes in your pieces
and not hav ing them collapse like a tin can on the interstate. I
find that for myself that the solder seams will almost always have
small holes that look like pits and even if I go back and stroke the
seam with my solder pik or add solder the “pits” just show up at
another spot. I feel it is almost alwa ys best to design my piece so
that I can have 1-2 small holes in an inconspi cuous spot. the time I
save is more then worth it.

Regards, Jerry


#7

My understanding is that when you first solder the hollow form
closed, you don’t have to worry about gas expansion and explosion.
It’s the next time you heat the piece that you have to worry, since
the gases are now trapped inside. That said, the author of the LJ
article should probably have advised drilling a vent hole before
soldering, just to be on the safe side and also because s/he doesn’t
know how the reader will use or abuse his/her instructions. Beth


#8
 I have a question regarding soldering.  I've been taught when
soldering hollow forms you should always have a hole in your piece
to let the heat escape. 

Its not the heat that is the problem, but the moisture. It is the
same as trying to pour a billet in a mold. If you don’t drive off
the moisture first, the resulting steam will blow the pour, or the
piece apart. The hole prevents a build up of pressure when the heat
is applied. I have seen hoop earrings explode when heated. It is
always a good idea to wear eye protection when soldering in case
this happens. If a piece of 14K at melting point hits you in the
forehead, it hurts like hell, but it will heal, If it hits you in
the eye, your sight may be gone. One close call was enough for me.
Wear eye protection.

Don


#9

My understanding is that when you first solder the hollow form
closed, you don’t have to worry about gas expansion and explosion.
It’s the next time you heat the piece that you have to worry, since
the gases are now trapped inside. That said, the author of the LJ
article should probably have advised drilling a vent hole before
soldering, just to be on the safe side and also because s/he doesn’t
know how the reader will use or abuse his/her instructions. Beth


#10
 I have a question regarding soldering.  I've been taught when
soldering hollow forms you should always have a hole in your piece
to let the heat escape. 

Its not the heat that is the problem, but the moisture. It is the
same as trying to pour a billet in a mold. If you don’t drive off
the moisture first, the resulting steam will blow the pour, or the
piece apart. The hole prevents a build up of pressure when the heat
is applied. I have seen hoop earrings explode when heated. It is
always a good idea to wear eye protection when soldering in case
this happens. If a piece of 14K at melting point hits you in the
forehead, it hurts like hell, but it will heal, If it hits you in
the eye, your sight may be gone. One close call was enough for me.
Wear eye protection.

Don


#11

I’m sure a lot of people find this out the hard way, I soldered a
new jump ring to a coffee bean pendant, and oh my god, it exploded
and I jumped through the roof!! I know now!! regards John


#12

Even if it is the “last soldering” to be done on the piece it is
poor practice to solder a hollow form with out a hole. It is very
possible that the seam will not completely seal the hollow form then
it will suck up pickle anyway, it only takes a microscopic pin hole
in the seam to do this. Then it can leach the pickle out on the
customer which is bad news and if it ever needs to have any repair
done to it it will not “surprise” the smith working on it if it is
vented.

Jim