Platinum laser wires differences

Ok so I finally popped for a laser. Its been awhile since I last
used one and I don’t recall what sorts of wire that shop used. My
question is… is there an observable difference between plat/ir wire
and plat/ru? Either cosmetically or structurally.

Also, I’m noticing that the wires can be had in.006,.008, and.010"
diameter. Functional differences?

Thanks

Ok so I finally popped for a laser. Its been awhile since I last
used one and I don't recall what sorts of wire that shop used. My
question is... is there an observable difference between plat/ir
wire and plat/ru? Either cosmetically or structurally. 

I find the iridum alloys weld better. cleaner and brighter welds,
less pitting. Pure platinum is also good to have, since it melts a
little below iridium platinum, good for delicate work.

Also, I'm noticing that the wires can be had in.006,.008, and.010"
diameter. Functional differences? 

Functionally it’s simple. thinner wire means lower power settings,
so working on delicate features and details is easier with thinner
wire. But larger welds then take corrospondingly longer time and more
passes to fully fill.

by the way, platinum laser wire is among the easiest to make of all
the metals you might need wire for, due to it’s extreme ductility and
slow work hardening. You can get nice carbide drawplates that go from
about 2.2mm down to .25 millimeters or so, and this smallest size is
a good all around size for much welding. I’ve got a small carbide
plate that goes down from.24 to.12mm, for when I need really fine
wire. I’ve never gone more than about halfway down that plate…

Given the cost of buying wire, making your own is worth the time. It
takes me perhaps fifteen minutes to turn some scrap platinum into a
coil of laser wire that will last me a month or two. Some metals that
work harden more, including 14K golds, nickle white golds, etc, are
more trouble. (anneal coils of thin wire in a kiln, and it gets easy
again), but still cost effective if you’re set up to do it.

Peter

I can’t speak for the difference between the two Plat alloys, as I
just usethe Plat/Ir. (I did use Plat Cobalt wire at my last job, for
working on PT/Cobalt castings only) The wire diameter does come into
play I find when working on the thinner pieces, where melting a
thicker wire can effect the much thinner sheet that I’m working on.
In most cases I run into this on hollow gold. I keep some much
heavier wire on hand when I need to fill a large area in heavier
pieces and where a thin wire would just take too much time and work
for the machine.

Good luck: after 5 years with a laser on hand I moved on to a new
shop w/o a laser. After 2 months I figured out a way to buy my own
laser, as I felt that I was working without my left arm. I have over
30 years at the bench with the torch, including 6 now with a laser
and there is just no way I would want to work without both these
tools on hand.

I usually use the plat/ir for most of my plat work even on plat/ru
rings, most of the time it seems to work better for me. Don’t know
what laser you have but stuller has a great blog site for laser
owners. If you use palladium get ready, it doesn’t laser good, you
can fill holes but so far I have not been able to laser anything
that needs holding strength like prongs. Most of the wire that I use
is 30 gauge. You are going to have a blast with the laser.

Bill Wismar

I keep both grades, as well as matching wire for all the metals I
use. I try to use the same metal as the piece is made of, obviously,
mainly for color match. I have not noticed much of a difference in
platinum wire, except for a very tiny difference in color and the 950
Ru seems to flow just a little tiny bit better. Silver just seems to
work better with solder wire. Don’t know why. Silver’s just a pain
with a laser to begin with. Hit it, nothing, crank it up, nothing,
crank it up again, nothing crank it up again, POW! Right through.
Orange Sharpie seems to help, but only on the first pulse or two, and
be careful you don’t set it on fire. It makes a terrible mess. Chaos
may create order, but exploded Orange Sharpie in the laser produces
swear words, alright.

Anybody figured out silver and the laser? Inquiring minds want to
know!

Dave

I find that laser welding smaller pieces of silver is not terribly
difficult. The welded silver will get too reflective, but the
application of red Sharpie (or any color Sharpie) allows the laser
pulse to “bite”. Due to the high reflection I often have to reapply
the Sharpie after each pulse. And yes the “Sharpie” is highly
flamable, isn’t it?

It is larger and thicker sterling welds that are difficult, to
impossible to do well. “Stress cracks” appear in welds that a moment
earlier looked OK. I found that switching to a newer "pulse shaping"
laser helped only marginally, as did using Argon gas.

Using the silver solder laser wire does seem to help, but I am not
satisfied by the look of the seams that soldering produces.

If anyone else has ideas on improving the quality of laser welding
sterling without solder, I would be more than happy to listen!!!

If you use palladium get ready, it doesn't laser good, you can fill
holes but so far I have not been able to laser anything that needs
holding strength like prongs 

I’ve heard about using argon for white gold, I wonder if this might
help with palladium too.

James,

I have a Zahntech laser and I size large and wide ss rings everyday
with stones and pearls. I just did a Mabe ss ring yeterday that was 8
ot 9 mm wide I wrap the pearl in a wet paper towel and at the weld
site I use a sharpe and draw a line on the weld and depending on the
ring I weld one side of the site and then grind almost all the way
through then re sharpe it and fill it with wire that is alloyed by
Zahntech that they sell.I also have a pair of reverse locking
tweezers to hold the ring and keep my fingers cool.As far as cracking
if I experience cracking I adjust the power and time settings either
my power is too high and I lower it and raise the time. I play around
with it until it stops cracking.I have noticed that certain alloys as
far as ss rings go crack more readily than others.

Good Luck
J Morley

Your intuition is correct: argon is a must. Also, you want to turn
down your voltage and beam duration (under 3 milliseconds) for
palladium, as overheating will embrittle it. Annealing the wire
helps too.

If you really want to make it perfect, blacken the wire and the area
to be welded to on the piece with a Sharpie and go even lower with
the power. Reapplying the black can get tedious for large fills, but
it’s worth it.

The power and annealing tips apply to the plasma welder (PUK3) too,
but not the blackening.

Jason
Casting House