More TIG type welding for jewelry

Actually its Plasma Arc Welding (PAW), very similar to TIG as
explained in a previous post.

Machine - Thermal Arc Ultima 150 (ebay score)
Material - 10 ga. Type 316L stainless steel wire
Project - Earrings

You can see the first project on my blog

http://www.patpruitt.com/blog/?p=21

I think there is a definate future for this type of welding in the
jewelry industry. Kevin has show the way with some of his TIG
techniques, this is a slight variation using slight different
equipment. But once again, industrial equipment and techniques that
are making its way into our industry can only be a good thing.

P@

Hi Pat -

I’m new to this list and jewelry in general but I’m also equipped
for TIG and intend to try it on some silver scrap over the weekend. I
emailed Kevin earlier this week. He indicated that he uses a WP50
and WP9 torch, .020" 1.5% Lanthanum electrode, DC- polarity. The
Lanthanum electrode is a non-radioactive equivalent of 2% thoriated
tungsten so if you weld carbon steel you should have all of the
necessary equipment - the 2% thoriated electrode should work just
fine. 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 happens.

Don

Lanthanum electrode is a non-radioactive equivalent of 2%
thoriated tungsten so if you weld carbon steel you should have all
of the necessary equipment - the 2% thoriated electrode should work
just fine. 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 happens. 

I’m really interested to hear how your efforts go. I have a Lincoln
TIG machine as well, same model as I recall. I’ve got a gas lens for
the torch and collets for.040 tungsten. Having done some TIG welding,
I think it has huge potential for jewelry work. One trick I’ve done
is to weld the ends of copper house wire together to form a loop
using a fusion weld. I’ve heard of others welding beer cans together.

Paul Anderson

I intend to start at about 5 to 10 amps and see what happens. 

It takes lots of current to TIG silver your 185 may not be enough to
get in and out before raising the whole mass to melting point. Kevin
is reporting using 300 amps to weld silver. My experience has been
similar.

James Binnion
@James_Binnion
James Binnion Metal Arts

360-756-6550

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
happens. 

Id say give it a shot, whats the wost, making more scrap silver :wink:

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.

P@

It takes lots of current to TIG silver your 185 may not be enough
to get in and out before raising the whole mass to melting point.
Kevin is reporting using 300 amps to weld silver. My experience
has been similar. 

Kevin indicated he was using a WP50 and occasionally a WP9 torch.
Those torches are only rated to 50 amps and 125 amps respectively.
I’m considering TIG for very small pin-point welds, not welding
large masses. Under what conditions are you using 300 amps?

I hadn’t considered thermal conductivity. Silver is certainly more
conductive than steel in that respect as well as being a very good
electrical conductor.

My argon supply hose decided to self destruct so the experiment will
have to wait until tomorrow.

Don

It takes lots of current to TIG silver your 185 may not be enough
to get in and out before raising the whole mass to melting point.
Kevin is reporting using 300 amps to weld silver. My experience has
been similar. 

300 amps! You could weld an aluminum engine block with that much!
I’ve done stick welding with a 1/4" rod(7018) and didn’t need that
much current.

Paul Anderson

300 amps! You could weld an aluminum engine block with that much!
I've done stick welding with a 1/4" rod(7018) and didn't need that
much current. 

Yes but your aluminum engine block has much less thermal and
electrical conductivity than the silver. You need huge amounts of
current to spot heat the silver fast enough to end up with a puddle
rather than melting the whole item. I work on steel, stainless,
copper and precious metals with a TIG torch. Copper of the same gage
as mild steel requires twice as much current as mild steel and silver
even more than that and stainless needs less current than mild. It is
all about thermal and electrical conductivity.

James Binnion
@James_Binnion
James Binnion Metal Arts

360-756-6550

300 amps! You could weld an aluminum engine block with that much!
I've done stick welding with a 1/4" rod(7018) and didn't need that
much current.

I think what James is getting at is that silver has such a high
thermal conductivity that you have to hit it with a lot of current to
melt the site to be welded before that heat is transmitted to the
adjacent structure. 300 amps scares me though - seems to me it would
go directly from solid to vapor phase :slight_smile:

Still waiting on parts…

Don

Yes but your aluminum engine block has much less thermal and
electrical conductivity than the silver. You need huge amounts of
current to spot heat the silver fast enough to end up with a
puddle rather than melting the whole item. 

This is just pure curiousity - have you tried welding it on a large
copper block to help keep the silver cool? I have some silver on
order, so I hope to be able to experiment with this shortly.

Paul Anderson

I hope to be able to experiment with this shortly. 

I got my TIG cable yesterday and finished welding up an ingot mold
for the scrap that I have. I left the welder set for 150 amps and
tried a 90 degree butt weld on some.018" sterling scrap sheet. I was
using a steel plate as a heat sink. Not surprisingly, just squeezing
the pedal blew a hole right through it. So I took it down to 5 amps.
I could just barely get a bead going and it was difficult to maintain
the arc. I took it up to 10 amps and that generated a more stable arc
with the pedal to the metal. Then I took it up to 30 amps to provide
the extra current if I needed it. It’s easy to control and I was able
to run a bead without penetrating completely through the sheet. I
used no filler rod (silver wire) of any kind. At minimum current, the
arc was about the size of a head of a pin and stable. The bead did
spread out a bit more than I was expecting. I’m sure with some of
practice this would be a very usable tool.

One thing I noticed is the arc will jump all over the place unless
the electrode is very close to the workpiece. This is most certainly
due to the higher electrical conductivity of silver.

Next I plan on melting some scrap into 1"x.5"x.5" ingots and running
some tests on it. The thermal mass will be significantly greater in
that case so more current will be needed.

The WP50 torch would be ideal for this sort of work I think.

3/32" 2% thoriated electrode, 30 amps DC-, 15cfh argon.

Don

This is just pure curiousity - have you tried welding it on a
large copper block to help keep the silver cool? I have some silver
on order, so I hope to be able to experiment with this shortly. 

No, it might work if you do your setup right but silver has higher
conductivity (both thermal and electrical than the copper and it may
be tricky.

James Binnion
@James_Binnion
James Binnion Metal Arts

360-756-6550

One thing I noticed is the arc will jump all over the place unless
the electrode is very close to the workpiece. This is most
certainly due to the higher electrical conductivity of silver. 

Do you have the tip of your electrode rounded or ground to a point?

Paul Anderson

Kevin indicated he was using a WP50 and occasionally a WP9 torch.

Don, It’s the other way around. I don’t know that it makes a
difference other than the shape of the torches are different. The
WP-9 has a larger tungsten and amperage capacity. I have a flex coil
in the handle which allows me to blend it in compound shapes and I
use a gas lens cap. I have a long back cap on it so I can put full
length pieces of tungsten in it. The WP-50 does not have a back cap.
Currently is unavailable with a flex coil and can not be fitted with
a gas lens. The large amperage weld was made with as a short duration
(dwell) as my machine is capable of: 1/10 of a second. http://
tinyurl.com/6pqtr3 These welds were over 2 mm in diameter.
Conductivity and area influence the amount of amperage. Consider that
it is very difficult for me to join a fiction post to 10 X 10 earring
plate. The post wants to melt away from the plate. After a tiny
connection between the post and plate is made the post then can have
a base fillet added with greater ease. I believe this is because the
post becomes part of the total 10 X 10 area in which electrons are
energized. I encourage you to try some welds. Find a machine that can
do spot welds as well as continuous runs of welds. See what happens
and let me know. Regards, Kevin

Kevin Lindsey

Do you have the tip of your electrode rounded or ground to a
point? 

Ground to a sharp point. Rounded is usually used for AC.

Don

Hi Kevin -

Consider that it is very difficult for me to join a fiction post to
10 X 10 earring plate. The post wants to melt away from the plate.
After a tiny connection between the post and plate is made the post
then can have a base fillet added with greater ease. I believe this
is because the post becomes part of the total 10 X 10 area in which
electrons are energized. I encourage you to try some welds. Find a
machine that can do spot welds as well as continuous runs of welds.
See what happens and let me know. 

I’ve been experimenting with some 24ga sheet and 20ga wire. I see
what you mean about welding the post in place. I currently am
experiencing about a 10% success rate. The wire melts very easily and
very suddenly. I use thin leather gloves while TIG welding. I
immediately noticed the amount of heat being conducted up the silver
wire. Contrasted to steel the difference is quite remarkable. I’m
using under 20amps. A spot weld might be ideal for attaching a post.

One of the major problems I’m having is that the arc doesn’t
initiate at the point of the electrode but often starts around the
cup. When this happens it makes a mess of things. I rarely see this
at higher current levels used on thicker gauge steel. I need to play
with argon flow rates to see if I can clear this up. The other
problem I’m having is with my helmet as it’s a #12 fixed shaded
helmet - my autodarkening helmet is on the fritz. It’s very difficult
to weld at low current levels with that degree of darkness. The issue
I’m having with the poor arc start could also be attributed to my
inability to see and position the electrode properly prior to
squeezing the pedal. A magnifying lens in the helmet would help too.

I don’t think any of the problems are insurmountable. Practice will
improve the success rate. Using a different alloy or hardness of the
post might help too. Something that really helps is cleaning the
parts thoroughly prior to welding.

What is the thickness of the 10x10 part you are attempting to weld?

Don

for welding on ear posts it is probably better to use a cap
discharge welder. see the sparkie: a at reactive

Jesse

Attachment: “Sparkie Fusion Welder.webarchive” removed

Welding with tig at low amps can be very hard on beginners and
advanced users. I welded with tig for 30+ yrs of about every metal
that welds. When using the small amp torches the difficulty is in
starting the arc that’s where a good high frequency setting and set
your highest amp with the dial. then when you press your pedal all
the way down it will give a burst to the arc and start it then you
can pull on the pedal to cool the arc. Welding a pin on any thing is
a challenge but if you can jig it so the pin is in a heat sink and
start your arc on the heavy base with a small filler material close
to the weld. you can start a puddle and move it to the post with the
right timing the weld will be good. Also the lens number should be a
least a ten to see in this low light level or a changing lens. Some
times in low amp we used dark cutting glasses with a jerry rigged
face shield. This was before we new what would happen in latter life.
from welding all these years My eyes are light sensitive and need
lower number lens to see. we had good luck with using ac and full
frequency on welding copper, brass any of the items that took high
amps to melt. also adding helium to the mix increased the heat
generated at the arc.

They make a pulsing tig which are great as they increase the amps
high to puddle the metal and cool the amps so it won’t melt and ruin
what you have made. mostly used on alum but I hade good results with
other metals also. But My pulsar was the cheap kind. Most of the
time my torch hand a switch to turn on and off with preset heat
hotter than I need and would toggle the switch to pulse or just move
really fast. Also the ceramic cup should be clean with no metal build
up and a long and sharp point on the tungsten yes I know 2% thorated
tungsten pure for AC welding.

For stainless steel on small item would use stainless steel safety
wire in a can was about .015 dia melts fast. great filler on copper
and brass would everduer wire can’t say the color matched but would
take the high heat and metal easy.

Also to high of gas setting can blow the arc and the puddle playing
with what you like is the only way not what the books says.

I have not done it but seen it the torches you use on welding gold
with the solder or maybe its a brazing material looks good for
welding most of the jewelry I see. Sharp edges and small dia pcs
will always metal first when the arc hits it starting the arc has to
bee on a heaver item and moving the arc will always leave a trail in
the metal some time when you stop the arc it will dimple or leave a
small hole and some times crack that’s when you have to run the arc
off the surface before shutting down

Hope this helps
Thanks Randy
AKA Enjen Joes