My torch is a larger WP17 with a 3/32" electrode but it should
suffice for test purposes. My TIG machine is a Lincoln Precision
TIG 185. I intend to start at about 5 to 10 amps and see what
Id say give it a shot, whats the wost, making more scrap silver
After playing around more with this plasma arc welder Ive noticed a
couple of things. I dont really think this plays into working with a
standard TIG machine as I dont have one for comparison sake.
1) The arc is controllable from a sharp flame to a very brushy type
flame. Keeping all settings the same, the variable is in the
electrode placement within the nozzle. At the sharpest setting the
flame is very directional, at a brushy setting it tends to wander to
the highest point neaby (shortest path of arc)
2) Fortunate for me, stainless is a very poor conductor keeping the
heat localized to form the molten puddle is pretty easy, the down
side its very quick, the plasma arc can heat stainless to a melting
point in fractions of a second (2550*F) even at very low amperages
(sub 10A), so working quickly and with precision takes some skill.
3) Shield gas is becoming a high consumable for this process. I
lowered the flow rate to almost half the recomended settings without
sacrificing quality of the shield. I might move from the 5%
hydrogen/95% Argon, to a pure argon if this continues, getting the
H2Ar mix is a couple day process for my local supplier, and thats a
one way hour drive for me, vs argon, they always have that in stock.
4) I do like the ability to add material to a piece if it needs
it. This helps with building up material to file down to get the
correct shape Im looking for. This is accomplished rather easily,
compared to doing this with a laser, building up a substantial,
homogenus section doesnt take all that much time.
5) sharp points do pose a problem, these melt fast, and the arc will
always get to these first.
6) Fusion welding any seam is tough. The flow of the ignited plasma
gas tends to round off the corners of any joint, once again, a
funcion of the sharp corner melting first, in addition to the force
of the flowing ignited plasma gas...It sort of just pushes it back.
Ill play with this more. This might be controled by the flame type.
7) Getting into tight corners is problematic, this is where a laser
would be the preferred method of jointery. Also, welding different
thickness materials is tricky, due to the heat required for the
larger pice vs. the smaller piece.
Yep, the continiuing adventures in plasma arc welding for jewelry
continues....questions? Just ask.