Micro Torches

I’m not certain what a Micro torch is. I have a mini torch that
I hook to oxy/acet. Is the micro the little butane thing? I
have wondered about those.

Thanks for your input! Susan

Can you please tell me how a torch is used for soldering, does
the flame heat the solder indirectly? I have just purchased
some copper solder in wire form, and was going to practice
soldering jump rings and earring backs to pieces…couldnt a
soldering iron do this as well? lynn

Hi Lynn,

  Can you please tell me how a torch is used for soldering,
does the flame heat the solder indirectly? 

Before soldering, the locations to be soldered should be cleaned
& fluxed. Depending on how you’re going to apply the solder,
pallions/snippets or wire, the solder may also have been placed.

In an ideal world, all the pieces to be joined by the solder
would reach the soldering temperature at the same time. However,
this is practically impossible to do because of the differing
sizes & locations of the pieces. Initially, play the flame around
the entire assembly to bring it up to temperature, but
concentrate the flame on the largest piece, close to the area to
be soldered. When soldering jump rings, both the left & right
sides of the join should be heated evenly. If one side reaches
soldering temp 1st, there’s a very good chance the solder will
migrate to that side of the ring, resulting in a weak or
unsoldered joint. When the piece is close to soldering temp, play
the heat on the largest piece at the base of the join. Watch for
the solder to turn shinny. When this happens, the soldering temp
has been reached. If the join is just a small spot, remove the
flame at this instant. If the join is a long seam, move the flame
along the seam, from the hottest location to a cooler location.
Watch the solder, the shinny line will follow the heat. The
flame should be directed at the base of the join on the largest
of the pieces.

      I have just purchased some copper solder in wire form,
and was going to practice soldering jump rings and earring
backs to pieces....couldnt a soldering iron do this as well? << 

A soldering iron could do this job, but typically soft solder
(solders that melt below about 600 deg F are called soft solders)
aren’t used in the jewelry trade. The primary component of
solders used for most precious metals is the metal they are to be
used on. These solders are generically called ‘hard’ solders.
They come in several different melting temps, but usually all the
temps are above 1000 deg F.

Soldering irons have a top temp range about 600 deg F. Torches
are usually used for jewelry work. A gas ( propane, acetylene,
butane, natural gas, hydrogen, MAPP etc.) is usually used to fuel
these torches. Sometimes the gas is mixed with oxygen or
compressed air for a hotter flame. The temperature of some of
these mixtures can reach over 4000 deg F.

Since most of the soldering you’ll be doing in jewelry work will
be with the ‘hard’ solders, you should make every effort to
become proficient with their use. The hard solders come in
several forms, wire, sheet, snippets (called pallions) & paste.
They also come in various melting temperatures, high (hard),
medium, low (easy), extra low (extra easy); there may be other
names & types, but you get the idea.

Which solder you use is dictated by the job at hand. If you know
you are going to be doing several more soldering operations on a
piece, you may want to use a solder with a high melting temp
(hard) 1st, followed by solders with lower melting temps. It
should be said, that once a solder has melted, the melting point
of that joint will be higher than the original melting point of
the solder used. It’s impossible to say how much higher, but it’s
high enough that the same temp solder can be used on another join
in close proximity to the 1st without un-soldering it. This may
take a little experience before 100% success is achieved.

To build up your experience level, try soldering small parts to
larger ones, butt joints, lines, wires to sheets & any other
shapes you can think of. You might also try making several joins
in close proximity, letting the entire assembly cool between each
soldering operation. Use all temps of solder. Which solder you
use, sheet, pallions, paste, or wire depends somewhat on the job
at hand & personal preference. Just a guess, but most jewelers
probably use sheet or pallions. If sheet is used, it’s cut into
snippets before use, wire can also be cut into snippets. Paste
solder has the flux mixed with it & is applied with a syringe.
This is practically advantageous when soldering a large number of
jump rings.

Good soldering technique is learned by ‘doing’; the more you do
the easier it becomes & the better you get! Don’t be afraid to
fail, we’ve all melted & unstuck our share of stuff.

Dave

Very thorough answer, thanks ! just one more question, if you
have to heat the whole piece, I am looking at Picture in RIo
Grande. what do people do for firescale, that I hear so much
about,(i am using copper), and must use it for experimentation
and cost sake, or should I even worry about it? I am mostly
interested in jumprings and wires, just to get the technique
down smoothly…thanks

Lynn, I was taught that a soldering iron is considered a “cold
join” which is not appropriate for “real” jewelry. When I
solder silver, I use a torch to heat the metal as well as the
solder which is high silver content, but not "silver solder’
that you buy at the hardware store. There is a lot of argument
about what is called what, but the technique I was taught was
called brazing…it joins silver to silver with silver and when
filed out does not leave a visible seam. When you get into your
class, I’m sure that your instructor can likely give you a more
detailed explanation, but the metalsmiths I’ve known do not use
a soldering iron at all for jewelry.

Don’t get so far ahead of yourself that you will have to unlearn
bad habits! Have a blast though! I do.

Regards,
Susan E. in Dallas

G’day Lynne Humphrey; you wrote;

   ....what do people do for firescale, that I hear so much > 
about, (i am using copper),...... 

Firescale will appear on copper when heated above 200 or 300C
but should be easily removed by a bath in warm sparex ( - it’s
sodium hydrogen sulphate, it’s also sodium bisulphate and also
pool pH adjuster). Or room temperature 10% sulphuric acid
(battery acid will work). The copper must be grease-free, (Wash
thoroughly with hot detergent solution) but it will still
tarnish fairly quickly in the atmosphere. VERY gentle
brushing with a bit of rag on a stick with the pickle will hasten
the process. I say VERY gentle brushing so as to avoid
splashes, and do wear eye protection and a plastic apron. Yes;
even with sparex which also makes holes in clothing on prolonged
exposure. You won’t know you have dropped a bit on your clothes
until you find a hole there a few days later. Although a bright
polish can be obtained with copper, which will help retard
tarnishing , to keep it for any length of time it should be
treated with a durable lacquer.

One of my jobs in the Royal Navy as a signalman was to clean and
polish the ship’s bell and all the brass and copper voice-pipes
in the Bridge when not on watch. I used to sneak a bit of acid
from the batteries we used for signalling lamps, then polished
with Brasso on cotton waste. A brilliant polish ensued, which
lasted all of two days in port, or an hour out in the North
Atlantic! But they wouldn’t let me lacquer them.

By the way, you can easily tell those who drop their hot job
straight into pickle: they are the ones with lacy shirt sleeves.

       / \
     /  /
   /  /                                
 /  /__| \      @John_Burgess2 who hates polishing, even by machine.
(______)       

At sunny Nelson NZ

Hi Lynn,

If you’re just using copper (mostly for experimentation &
practice), I wouldn’t worry about fire scale. That’s unless you
hope to sell some of the copper creations (some folks swear by
copper bracelets as a help for rheumatism). It’s the copper in
the silver/gold alloys that cause the fire scale. Usually just
pickling the copper & then polishing it leaves a satisfactory
finish.

If you want to try a fire scale preventative, you can mix your
own. Mix as much powdered boric acid (available at the drug
store) as will dissolve in a small amount (aprox 4-6 ounces) of
denatured alcohol (available at a paint or hardware store). Paint
this solution on the object or dip the object in it. Then light
the object to burn the alcohol off. Be sure to close the bottle &
move it out of the ay first. Alcohol burns with a hard to see
(essentially invisible) flame, so be careful. After the alcohol
has burned off, the boric acid will be left on the surface of
the item. When the item is heated, the boric acid forms a shield
over it keeping the oxygen in the air from joining with the
copper forming a copper oxide. There are also a number of
commercial products available to prevent fire scale.

If you’re going to be soldering mostly wire, I’d suggest using
paste solder. Paste solder is very finely ground solder metal
mixed with a flux & a carrier vehicle (usually glycerin). It’s
packaged in syringes that are usually supplied with 1 or 2 small
needles for applying the solder to the desired location. There’s
no need for the application of any additional flux & because the
paste is ‘sticky’ it stays where it’s put. Paste solders are
available in most heat ranges as well as alloys( sterling, GF,
10K, etc.). Many paste solders use some type of fluoride
compound in the flux. If you’ve got health issues or concerns
verify any hazards use of the product may cause.

If, however, you want to become adept at solder placement with a
solder pick, you might want to use pallions or snippets & flux.

Dave