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View Full Version : How to cut this piece?



Bob WrightNC
05-29-2012, 11:46 PM
My wife is fond of this type of jewelry and I'm curious as to just what equipment it would take to cut it out. It's pewter but they also do this in sterling silver.


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Steve knight
05-29-2012, 11:48 PM
cast or get out your jewelers saw.

Bob WrightNC
05-30-2012, 12:13 AM
Steve, I guess that's why they call it cut out jewelry then. I just thought it might be done with CNC or some other way. Went and watched a video on casting after I saw your post - pretty cool but at this point in my life, I'm not sure how much room is left upstairs to add something new along with everything else I'm trying to tackle. Thanks.

Bruce Hoffman
05-30-2012, 2:30 AM
1) Laser a piece of wax in the design you create in Corel. Cast wax in silver or gold.

2) Laser "Engrave" a reverse pattern in soapstone and melt a soft metal [pewter] into the mold.

3) Laser a pattern on some suitable [perishable] material: plastic, wax, foil or thin wood. Apply "precious metal clay" to pattern, heat in oven or heat with torch. When heated the PMC will yield a nice precious metal piece.

Get creative, mix and match some of the above.

Bruce Boone
05-30-2012, 9:26 AM
Or it can take a YAG or fiber cutting laser. They have extremely fine kerf and good quality of cut.

Doug Griffith
05-30-2012, 9:37 AM
The soft edges tell me it's cast. Probably spin cast to get the fine detail. If you find a way to cut this, you will still have to deal with softening the edges. Tumbling in a very fine medium may get the job done.

Bob WrightNC
05-30-2012, 10:00 AM
Great responses - thanks guys. Keep 'em coming. The wheels are spinning, squeaking a little bit, but still spinning. :)

Bob WrightNC
05-30-2012, 10:21 AM
Question - the rounded edges on the piece - how would you design that? In other words, how do I design the "softness" instead of sharp crisp edges in the wax, or is that a function of the tumbling/finishing?

Doug Griffith
05-30-2012, 11:19 AM
Question - the rounded edges on the piece - how would you design that? In other words, how do I design the "softness" instead of sharp crisp edges in the wax, or is that a function of the tumbling/finishing?

Tumbling/finishing.

If you go the wax route, it might help to soften the male plug's edges prior to casting. Something like using kerosene and a small paintbrush.

Richard Rumancik
05-30-2012, 1:00 PM
Was the laser-cut wax just a suggestion to try? Or has anyone here actually had success in laser cutting wax? If so what kind of wax did you use?

I have not had any success with wax and would not be able to generate the kind of detail shown. Wax tends to melt far from the kerf as it has a very low melting temperature; then wants to flow back on the kerf. I was unable to get any real definition with the wax and settings I was using.

One process a jewelry manufacturer might use would be to make a master pattern in acrylic, soften the edges, and make a silicone mold of it. Then use a wax injector to make muliple wax parts; then use standard jewelry casting (investment cast) techniques after that.

Or you could laser cut several acrylic masters and use them to make a spin casting mold. Rodne has written about this process a few times. You probably don't want to get into the casting process but you could make the masters and subcontract to a spin caster.

Bruce Boone
05-30-2012, 1:15 PM
The inlay in this pen was done that way. There is special wax made for jewelers to machine. It's stiff and doesn't just gum up a cutter. The cutters used have a tip about .003" or so. The wax is made to burn out completely in the lost wax process. It comes in sheets and rods. The bird insert was cast in sterling silver.
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Doug Griffith
05-30-2012, 1:19 PM
I was thinking lost wax casting. Creating the female "tool" out of acrylic with the laser.

Terry Albrecht
05-30-2012, 1:30 PM
This type of project can be done in a couple of ways. I believe if you use a precious metal gold/silver with a yag laser you will lose too much metal and wouldn't be cost effective. If you hve the proper equipment you could roll out some metal, cut the circle out and then cut out the letters from there. Again unless you do much of this and can recycle the wasted metal it isn't cost effective. I do these type of things all the time and use CAD software, CNC mill, cast and polish. Using a tumbler doesn't really give you the rounded/soft edges but using a polishing motor will unless in the CAD you create them originally. If I had no equipment to do this type of work I would probably get a silver disk from a store, draw out the pattern and cut it out with a jewelers saw. Then I would get some really fine sandpaper, cut it into thin strips and go along the edges to round them off. Or you could get a jeweler buddy to hit it with their polishing motor and the edges would round off.

Bob WrightNC
05-30-2012, 1:52 PM
The inlay in this pen was done that way. There is special wax made for jewelers to machine. It's stiff and doesn't just gum up a cutter. The cutters used have a tip about .003" or so. The wax is made to burn out completely in the lost wax process. It comes in sheets and rods. The bird insert was cast in sterling silver.
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Interesting Bruce that I talked with a company that you could outsource the spincasting to and they talked about using "carving wax" and that it came in three grades, Blue, Purple, and Green with the difference being in hardness. So I'm going to look into this option and I'm guessing this may be something I could cut out with an engraver if I wanted? Anyone had any experience with that?

Bruce Boone
05-30-2012, 3:14 PM
Yes, that's the stuff. That's where those tiny endmills come in. I used a CNC mill with a Foredom 18,000rpm motor to do it. Places like bits and bits www.bitsbits.com (http://www.bitsbits.com) have special endmills just for wax. They are like a needle and you can get some awesome detail

Bob WrightNC
05-30-2012, 3:24 PM
Yes, that's the stuff. That's where those tiny endmills come in. I used a CNC mill with a Foredom 18,000rpm motor to do it. Places like bits and bits www.bitsbits.com (http://www.bitsbits.com) have special endmills just for wax. They are like a needle and you can get some awesome detail

Just curious Bruce if there would be a tool to engrave with that would give you the same type of detail since I know one company does a demo engraving wax.

Bruce Boone
05-30-2012, 5:38 PM
It can be a ball endmill or a tapered pointy mill. As long as the stepover is very small, it doesn't matter much what the cutter profile is.

matthew knott
05-30-2012, 6:21 PM
laser cutting would be quick and digital and waste material could be melted down and used again,
http://www.youtube.com/watch?v=VXcpjS6qNeY&feature=player_embedded

Rodne Gold
05-31-2012, 2:15 AM
Was the laser-cut wax just a suggestion to try? Or has anyone here actually had success in laser cutting wax? If so what kind of wax did you use?

I have not had any success with wax and would not be able to generate the kind of detail shown. Wax tends to melt far from the kerf as it has a very low melting temperature; then wants to flow back on the kerf. I was unable to get any real definition with the wax and settings I was using.


It's impossible to laser wax in any meaningful way , I have tried with dental , jewellers , various candlewaxes , freezing it etc.. no go. Easy to use on a computerised engraver tho...