Laser welding silver

Hello everybody. I have taken the plunge into the area of laser
welding sterling silver, but I have not succeeded in making welds
that are durable and does not break. Is that possible at all? or will
a weld never be as good as a soldering when it comes to durability?
What is the best material to add and does it matter weather or not
the material is clean? I have used a blue marker to avoid reflection,
perhaps there is a better material? Does anyone know a lot about this
area and be willing to share with a beginner? Or where can I read
about the subject? What a lot of questions. Hope you can help me.

Lone

Lone, Use SS solder instead of wire as a filler. I no longer mask
the SS with a marker and get good, durable welds, without porosity.

My suggestion: don’t fight it, use the solder and weld it in with
your laser. Works well for me.

Bob Staley
B.Staley, Goldsmiths
Precision Laser Welding

Dear Lone: Suggest you first identify if you are filling the welding
chamber with a inert gas (suggest argon)? It is our experience that
the inert gas helps to ensure a homogeneous alloy flow when welding
most precious alloys. In respect to silver, the higher to purity,
the faster the heat disapates from the welding bombardment zone. It
is important to configure your pulse energy output to take advantage
of a lower voltage setting while using longer milli-seconds. The
theory is to heat the metal slightly slower and allow it to flow,
rather than crystalize and become brittle. Some of the new machines
available today offer Energy Pulse Shaping software which also
improves the flow of alloys.

Traditionally silver requires a higher pulse energy output (joules)
than gold or platinum. Since I do not know the make of the machine
you are using nor the silver application, I cannot help you with the
suggested recommended parameter settings. Normally, silver
applications need a minimum of 100+ joules of hot light energy. You
should check the serial label on the machine and it will indicate the
joule energy output.

Also, many of our clients benefit from adding a filler wire to
ensure a strong laser weld. 65% silver-solder wire works well in a
diameter of .010" / 0,25mm.

If you have further questions please do not hesitate to contact us
for applications assistance.

James Gervais LaserStar Learning Center
Email: lasertraining@crafford.com

   Hello everybody. I have taken the plunge into the area of laser
welding sterling silver, but I have not succeeded in making welds
that are durable and does not break. 

Lone, Of the various jewelery metals, silver takes the highest energy
levels to weld, which can make it difficult. As well, the welds
produced tend to be brittle. this is not unique to silver, as welds
in most metals come from the machine quite work hardened, especially
with shorter pulse lengths. The metal is cooling so quickly that it
doesn’t have time to form a reasonably cohesive and orderly/uniform
grain structure. The effect is much the same as with electroformed
metal, which also can be highly work hardened and brittle as it comes
from the bath. Use longer pulse lengths, and, if needed, lower
voltage, to get the weld to form a little more slowly, giving the
metal a little more cooling time. . Your goal among other things, is
a weld without those little cracks forming across the weld as it
cools, especially with shallow depth welds such as you get when
smoothing off a weld with pulses at a wide focus, that just barely
glaze the surface. Looks nice, but beware of those surface cracks.
If they form, they can extend into the weld later. So as a first
step, work for a weld without those little crazing marks. if you can
get that, then even if the weld is hard and brittle, it is, at least,
sound. And if the piece will withstand some gentle torch heating,
you can gently anneal or stress relieve the weld. Obviously, this
doesn’t work for pieces which cannot withstand heating, but if you
can do this, then after annealing, the weld will be strong and
durable. Not quite like native metal, but very close, and far better
than a solder seam.

46or difficult to weld items, it may help to use a filler wire of a
lower silver content alloy. I’ve used all three of the major grades
of silver solder (easy, medium, hard), and they’re all an improvement
over using straight sterling silver filler wire. Of course, then
you’re back to the color mismatch problems with solder in the first
place. Generally, for that reason, I use hard silver solder as
filler, when filler is needed.

Those lasers offering pulse shaping ability will be better able to
produce a solid good weld in silver. A pulse that starts off at full
power, enough to melt the silver, then drops down in power for the
remainder of the pulse, lets you use a longer pulse for better
penetration, without overdoing things. And a pulse that doesn’t just
shut off at the end , but tapers off, allows some brief stress
relieving or annealing action, especially with longer pulse lengths.
Some lasers have these functions automatically built in, others
allow you to program what you wish. Most older models (over three
years or so), don’t offer this, unfortunately. But you can still play
with the settings a lot, and usually there will be something that
will work.

Peter

With all due respect to Mr.Gervais, I would disagree with his
statement:

 Suggest you first identify if you are filling the welding 
chamber with a inert gas (suggest argon)?  It is our experience
that the inert gas helps to ensure a homogeneous alloy flow when
welding most precious alloys.

First, you don’t “fill the chamber with an inert gas.” It is
actually not possible with the lasers used in the jewelry industry to
fill the chamber with argon or any other inert gas. Assuming here,
but I don’t think he meant to say that you do, but the statement
could confuse and mislead someone and cause frustration if taken
literally. When using inert gas (I do use Argon, as he also
suggested) make sure the gas nozzle is as close to the piece you are
lasering as you can get it. You will not replace the ambient air in
the chamber with inert gas without a vaccum to remove the air, then
you wouldn’t need the inert gas, would you? Just be sure the weld
zone is flooded with the gas (hence the close proximity of the nozzle
to the piece you are welding). I have many “hits” on my gas nozzle
from getting close to the piece I’m working on. IMO, it is the key
to successful lasering when you do have to use an inert gas. Secondly,
in my experience, argon can acutally be counterproductive if used
with certain metals. I get much better welds and finishes NOT using
argon on 14k yellow gold and on platinum. I don’t use argon on
sterling silver and my laser is rated to 95 joules-- I don’t max it
out when lasering silver, either. Use the silver solder to fill with
and save yourself some grief. You won’t have to mask the weld zone
with a marker, either. Argon with Titanium is a must. It helps to
use it when lasering steel. It gets expensive to use argon all the
time. I simply don’t do it, and I get good results. Again, not to
slight Mr.Gervais, who I’m sure is quite knowledgeable on the
manufacturing of lasers, but I’m speaking from my own 2600+ hrs of
laser welding experience over the past four years on all types of
jewelry and metals with the laser. I have a wholesale laser welding
service to the jewelry trade and currently have well over 100
clients nationwide who at least occasionally use my service, sending
me all kinds of pieces for repair. I’m “in the trenches” daily using
my laser. I am no expert, I’m just experienced. This is my
experience. My suggestions are just that, suggestions. Laser
welding is an art. Trial and error, experimentation and
documentation, are the keys to success.

Wishing you much success!

Bob Staley
B.Staley, Goldsmiths
Precision Laser Welding

With all due respect to Mr. Bob Staley, it seems he has become
somewhat “troubled” by my suggestions and he wishes to move this
discussion to a higher level. Let me take this opportunity to be
alittle more precise.

My statement “filling the chamber with inert gas” was a figure of
speech.

“When activating the inert gas flow on a 6000 or 7000 series
LaserStar Workstation, the system precisely releases a continuous
flow of inert gas* into the “welding zone / focal plane” creating a
"cloud” of atmosphere in the area where welding will be performed.
This gas will continue to flow replenishing the cloud until the
operator has released the footpedal device which also indicates under
normal circumstances that the current “hot light” discharge has been
completed.

*(possibly Argon, yet many users are benefiting from Nitrogen which
is also an import gas used in the casting of Silver)

Mr. Bob Staley is using an older model of laser welding
machine…vintage 1998. I know this since I sold him the machine.
The gas delivery system in current generation LaserStar Workstations
have a “proprietary” gas delivery system which eliminates the
possibility of “hits” on the movable gas nozzle and eliminates the
need for operators to have to fumble attempting to correctly position
the nozzle. This older design did not always ensure consistant nor
correct direction flow of the gas, hence his frustration when using a
inert gas and suggestions that he achieved no benefits on gold or
platinum.

Using a inert gas only improves the laser welding process while
helping to reduce any “contaminants” from influencing the homogeneous
weld quality. Micro-welding can in fct occure using a laser without a
inert gas, yet at a minimum it improves the “cleanliness” of the
welding area and in many cases enhances the welding results.

Secondly, it is import to clarify that I was not implying that one
must “max out” the laser system to weld silver. I was only
identifying what levels of energy output are recommended to provide
the operator with the widest range of “pulse energy” to complete
most, if not all, of the laser welding jobs which may come across
one’s bench.

Silver solder wire will greatly assist your bonding process. Be
sure to have a diameter small eneough to properly flow the material
using the laser.

Many of you have heard the term “there are many ways to skin a cat”.
This also holds true when approaching laser welding tasks. If we
were to ask 10 experienced laser welders to perform the same welding
task, each would achieve acceptable results, but have arrived at the
end result using different combinations of parameter settings,
alignment skills, and multi-step welding techniques to produce the
finished piece.

I do not profess to be a practicing bench jeweler, yet I have been
involved in laser welding since 1994 and have assisted many jewelry
manufacturers as well as retail mfg. jewelers advance their
"processes" for bonding alloys. I bring my suggestions to the table
based upon my own experiences and draw upon the feedback and
experience of the 1200+ “laserstar users” our company has been
servicing since 1994 in the jewelry, dental laboratory,
aerospace(NASA), automotive, tool & die, and micro electronic
markets.

I wish LONE good luck and our LaserStar Learning Center is always
available to assist users of all make and model of laser machine.

James Gervais
Executive Vice President
Crafford-LaserStar Technologies

Mr Gervais is incorrect about two things. One, I’m a not "troubled,“
by his misleading “figure of speech” comments on “filling the welding
chamber with inert gas.” I was clarifying the his mis-statement for
the benefit of Lone. Secondly, I have no frustration when welding,
with or without using an inert gas. In fact, I’ve been quiet
sucessful as a laser welder. The techniques I use have helped me
greatly and again are suggestions for Lone to consider. I did
purchase my machine from Mr.Gervais’ company when he was a
distributor for the Baasel machine. He now produces a different
machine. Much like the racing industry…there are those who build
cars and those who race them. Information from both sides is
important. I speak from what I have experienced, personally, on a
daily, hands on basis -not from a techinical manual. I couldn’t build
a laser, and frankly have no desire to do so. I’m a pretty good
"driver,” though. I have had many laser uses who have called me
with laser welding issues and problems, including users who own the
machine Mr. Gervais sells. Some of the users of Mr.Gervais laser
were, in fact, referred to me by his company. Occasionally laser
owners have problems when welding. Many problems I’ve heard pertain
to welding sterling silver and welding titanium. I have had some
experience here and am always glad to share what I have experienced
with others. A wise fellow once told me , “take advice like eating
fish, eat the good part and throw away the bones.”

Bob Staley
B.Staley, Goldsmiths
Precision Laser Welding

Hi everyone,

Another little trick with welding silver, that I have used
successfully, is to use a black permanant marker to paint along the
seam as you weld. I think it helds to cut down the reflectivity of
the silver object and the shot gets absorbed instead of bouncing
off. I am not to sure on the science but it works a treat.

Best wishes for the holiday season

Terence M Dillon
Chivali Artisan Goldsmiths

Has anyone cracked the code for this? I am having a difficult time,
especially with ring shanks. The welds look great but they seem to
crack fairly quickly with normal wear. My best results are using
Argentium wire with a spike shaped pulse at 270 volts on standard
sterling pieces.

The other local jewelers keep sending me their problem repairs. You
know the ones. The customers that won’t take no for an answer.

Stephen Walker

Stephan,

I have a Zahntech Laser. The settings vary from yours. Though when
silver cracks at the weld point I usually turn down the power reduce
the beam size and or time. I juggle all three. I size these rings
from China that are “designer rings” all the stones are GLUED in they
are massive and the silver is a mess they are heavily rhodium plated
and they are stamped sterling and Clhoe is the maufacturer. I use an
alloy wire that Zahntech sells it has great properties and I have yet
to have a ring silver ring come back. I size all the rings on my
laser. I have a trade shop. If I’m having a tough time I will tack
the weld seam on one side then grind almost all the way through the
other side of the weld seam and fill it in with the Zahntech silver
alloy wire. I’m assuming you are coloring the weld before hand with a
black sharpie.

Cheers
J Morley Goldsmith Laser welding

Hi Stephen

Don’t feel bad if you struggle with silver on the laser. It’s high
reflectivity makes it hard to weld. I have been trying to make it
work for years, and still have issues. I do a few things to help
increase effectivesness. I usually run close to 300 Volts, with
about 4.0 MS, and a fairly narrow diameter ( 10 - 12 ). I will scuff
the surface with emery, or use a black magic marker to reduce
reflection. It’s a pertty intense charge, and it will heat it up
quickly so take your time. I have also found that Stuller’s silver
hard weld wire works the best for me.

With heavy shank rings, it is hard to get the penetration, and I have
found that sometimes I have to go back and anneal the shank after I
have laser welded it. It makes welding them on the laser a bit moot.
I often just doing them with a torch anyways…and many times,
bad as it sounds, I just say no thanks! There’s times when it is just
not worth the time spent.

Good Luck
Dave Mereski

Boy, I’ll be watching this one with baited breath!

Using medium or easy silver solder wire drawn down to 30 gauge is the
only thing that works for us, that and using an orange colored
Sharpie which blows off at the first pulse. Be careful you don’t set
the Sharpie on fire. We’ve done that a couple of times. Makes a
mess!

I too struggle with heavier sterling. Often the stress cracks are
visible partway through the welding process. When you see the crack
first appear you know the battle is lost. Marking pen, Argon,
Argentium, step down pulsing, all are some help (it is possible to
use silver solder, but that defeats the purpose of welding), but I
still am looking for the right “magic”. I have gone back to the torch
for all heavier shank sizings, and use the laser only to fill pits of
these rings. If any one has solved this sterling/laserdilemma, I’d
really like to know!

Has anyone tried graphite along the seam/joint?

Used extensively in industries that laser weld aluminium, and is
well known as a light absorbing medium.

Best Regards
Neil George
954-572-5829

I have also struggled with this. One trick I have used is to put the
machine on highest settings and fire three times in the initial
stages. I also use the argentium laser wire for aid.

It would help to know which machine you are using, I could probably
help more.

All the best,
Suz Andreasen
Www.suzandreasen.com

Has anyone tried using Platinum Sterling Silver wire to laser silver?
I have read about it but haven’t tried it. I thought that because
platinum lasers so well, perhaps the platinum content in the plat
sterling silver wire would improve the quality of the welds and
reduce its brittleness. http://www.abipreciousmetals.com/PG.htm

Mark

Using the Argentium laser works great on these thicker shanks.
280-300 volts, 4.0 ms, beam @12 to add wire. I am not a fan of the
sharpie, but if I absolutely need to use, blue is my preference.
Scuffing the surface with sanding disc or emery paper works best for
me. Also, keep an eye on the seam, if the metal looks spongy, lower
your setting.

Hope this helps.

S. Grayson Carroll II
Laser Sales/Trainer

The one thing I have tried and it work well. Try using argon gas…

Andy The Tool Guy Kroungold
Phone 800-877-7777 ext 4194
Fax 337-262-7791