White metal and PUK

Hello

I am new to the Orchid family, with academic background of
accountancy. However, working with metals for jewelry is my hobby. I
don’t know much about this field but am learning sharply through your
interesting forum. The other day I read the term ‘PUK’ with regard to
’white metal repair’. What is white metal and what does PUK mean?

Regards
Burhan Ahmad

The PUK is a term for a welder like the PUK 2 welder. It is simply a
tack welder. Concerning the white metal because of its high
reflectivity of the arc you need to darken the area that is to be
welded, usually with a marks a lot pen.

Russ Hyder
The Jewelry CAD Institute

“White metal” is a generic term for the non-precious metal used in
costume jewellery. It is characterised by its low melting point and
white colour. It is usually low density. PUK is the brand name of a
precision micro-welding machine made by Lampert Werktechnik. See
http://www.lampert.info/web/

Regards, Gary Wooding

The PUK is a term for a welder like the PUK 2 welder. It is simply
a tack welder. Concerning the white metal because of its high
reflectivity of the arc you need to darken the area that is to be
welded, usually with a marks a lot pen. 

A PUK is a brand of pulse arc welder, it is a Tungsten Inert Gas
(TIG) welding tool. It is different from a tack welder in that it
welds by striking an arc between a tungsten electrode and the work to
melt a weld pool. A tack welder strikes the arc between two pieces of
the work item like say an ear post and earring.

There is no need to darken the metal, you must be thinking about a
laser where that is sometimes needed. Anything used to darken the
metal would just contaminate the weld.

James Binnion
James Binnion Metal Arts

Russ,

I have heard of craftsmen using a marker on white metals for laser
welding, but I am unaware of this technique being an advantage to arc
welding. I often make a bright cut in precious white metal to drawn
the arc to that exact spot. I am using a high frequency start and TIG
which has no contact during the weld cycle. The PUC uses a lift arc
start with TIG in spot welding mode. Arc initiation begins with the
tungsten contacting the work. Technically the PUK is a rapid cycle
spot welder. It is not necessary to have both halves of the joint in
contact with each other in order to initiate an arc as with tack
welding.

Well I have had success with this method, especially with silver.
Agreed the differences of the tack and pulse.

Well I have had success with this method, especially with silver.
Agreed the differences of the tack and pulse.

We’ve been using a PUK 2 welder for about 3 yrs now. Hate to
contradict but we DO use a black sharpie to darken the area AROUND
where the weld is going to take place when welding silver-just not at
the spot we want to weld. Like using a laser, too much reflection
from the silver causes bouncing and no weld. This technique is good
for welding in tight places. If we don’t do that, then the arc will
blast metal away instead of welding. We’ve changed power settings,
etc but once we started using the marking pen to darken the area

If we don’t do that, then the arc will blast metal away instead of
welding.

I find this informative. I do have some questions. Does this
technique work equally well on all metal? Can you describe the blast
in greater detail? Do you get spatter? Do you get a round edged
crater? What amperage setting are you at? What is your argon
pressure set at? Are you scratch brush cleaning prior to sharpie? Are
you using any form of flux prior or after the sharpie? I am wondering
about the alcohol in the sharpie ink and it’s possible effect on the
process. I am also wondering if carbon is used in the ink formula. I
will try some test welds and post my observations.