Sizing a ring with the laser welder

I was wondering how many of you laser welders are using Rofin’s
method of butt welding when sizing. David Brown demonstrated this
technique at the advanced laser seminar and have found it to really
work. What it basically is kick up the volts and ms and take the hz
and beam diameter to 0. Blast a 50% penetration a few times and
repeat this on the inside of the ring. Then widen the beam to 5 and
fill in those gaps. Fill the rest in with filler. I was wondering
what other methods you guys are using. Scott Isaacs Berry’s Jewelry
-Nashville,Tn castgold@comcast.net

Scott, I usually take a pair of side cutters (if the ring is thin
enough) and cut each side of the ring. This leaves a good v shape
when the ends come together. Then I weld this and fill with wire. I
don’t have to crank the welder up on a high setting doing it this
way.

If the ring is heavy, I use the saw to make the v shape on each side.

Regards,
Ken
www.sandersjewelery.com

What it basically is  kick up the volts and ms and take the hz and
beam diameter to 0. Blast a 50% penetration a few times and repeat
this on the inside of the ring. 

David didn’t show me this, the folks at Alpha supply who sold me my
own laser did, mentioning that this was the way all the guys in the
Indian factories did it. With a typical ladies size platinum ring
shank, a little as one shot at 410 volts, 10 milliseconds, zero
focus, can completely weld through the entire shank, with just a bit
of filling in then needed, which I usually do around 330 volts, 3-4
miliseconds, and a focus around 15 for a nice smooth deposit… Much
faster indeed. And because the sizing joint is carefully fitted just
like with soldering methods, measureing exact amounts of metal to
add or remove in sizing is as accurate as with traditional methods,
which may not always be the case if you’re doing it by leaving a
significant gap to gradually fill in with smaller welds. Works well
with other metals too, though with some one needs to be careful not
to crank up the volts too high, or one starts to get significant
porosity from splashing too much metal around, especially with older
lasers that don’t have pulse shaping technology. The main downside,
of course, to this method is that running the laser at the higher
end of it’s voltage and power range can significantly shorten the
life of the flash lamp. So one needs to balance the cost of more
frequent replacements of the lamp with the time saved using this
method.

cheers
Peter Rowe