Stereolithography and computer-aided jewelry design

Aloha, I have been following this for the last week and thought
I would put in my two cents. In regard to stereolithography
versus CNC. We are talking apples and oranges. A
stereolithography device requires a surface modeler (JewelCAD,
Rhino3D, ETC.) that can out put a STL. file, in order to
machine it on a CNC, you need to have a CAM program to
postprocess the file, to make it understandable (G-Code) to a
milling machine. A STL. output machine can do undercuts, a mill
cannot (unless its 5 axis) and a mill can machine any material,
an STL. device only makes prototypes for casting, tools for
casting, or prototypes for visual representation. It will take
up to 18 hours or more to generate a wax ( though you can they
say you can do 10 at a time) for a part. A mill, 30 minutes to 1
hour, plus design time in a drawing package (like CoreDRAW). I
am a Technical Representative for Modelmaster and MasterCAM
(Educational Tech rep). I am not a salesman (though I am a
dealer). I use this technology everyday (I have two 4 Axis
mills).The technology is there, for those that want to make the
plunge. Modelmaster will have a stereolithography device out by
January (we are beta testing 10, and looking for a few more
sites, if interested), that will be half the price of available
units. Also we offer Rhino3D and JewelCAD (surface modelers), as
well as ArtCAM Pro (3D engraving/milling).Some individuals seem
to just want to design on computer, others want to take the next
step. Go for it. I can design a part, that would take 2 days to
lay out and carve, in 1 1/2 hours. How productive could it make
you? Let’s continue this discussion or feel free to contact me
of list.

Best Regards,

Christian Grunewald
Precision Modelmaking

I’m somewhat disappointed that you feel that it takes 18 hours
to produce a ring on the Model Maker. Less than 6 and with
several it gets better. Regarding Jewelcad, you don’t have the
rights to sell it.

Aloha Rolf, I suggest you check your resources before you
embarrass people (or yourself), on an international forum. I
wouldn’t do it to you. If you have a problem (in regard to
JewelCAD), I suggest you contact Model Master or contact me, off
list. And yes, you well know, based on the slice data, you can
blow out a ring quickly, but the surface finish suffers for it. I
have seen output from Sanders in both modes and there is a big
difference. In my humble opinion, Mills are more versatile,
quicker, a faster return on your investment and a more cost
effective solution, anyway. I don’t just sell them, I use them
(2), and have sat at the bench as a certified jeweler and
modelmaker for over 27 years (began in CAD/CAM and machine tools
over 10 years ago). There is no intention of debasing anyone,
people come here to ask questions and have discussions. If you
want to discuss the subject, instead of pushing product (aside
from the occasional mention), you may be better served. If this
leads to a real discussion, the forum would benefit with the
added knowledge derived, if not, you have my phone number (and

Best Regards,

Christian Grunewald
Precision Modelmaking

Christian, I have not pushed any product. I gave away 100
Jewelcad’s for people to try. I don’t sell Jewelcad. If
someone wants to use a milling machine, that’s great. If
someone wants to use an SLA machine, that’s also great and if
someone wants to use a Sanders machine, that’s even better.

You’re the one that stated that it took 14 hours to build a ring
on the Sanders machine, not me. I wonder, if this is true, how
long would it take to do by hand or even better a milling

Slice data doesn’t mean thick slices, it means surface data
instead of STL data. The slices can be as thin as .012 mm or 12
microns or .0005 inches, whichever you prefer.


Hi Rolf and Christian,

Some rings take 14 hours some take 3 hours, regardless of time
you always get perfection and making duplicates perfectly is a

Technology is what it is, use what’s best for the specific
job at that time, We use all of the technologies to OUR


Aloha Emil, I agree wholeheartedly, so now the quest begins.
Everyone seems to have the solution, but the real problem is
getting everyone from management, the design department, and
production, (And maybe even to the end consumer), on the same
page. (As Dominic Ventura suggested) And that is digitally. The
end justifies the means, whether it is handmade, hand drawn on
paper, solid or surface modeled or from a CAM package. The main
thing is to convey an idea or a design for production. The final
product is output to a modelmaker or a machine for prototyping.
The time for some is important, the output is more important.
The technology is now inexpensive enough for mom and pop stores
to get involved and this will bring a whole new crop of new
designers to the marketplace. The question is, What do you want
to do? And then, decide your path. Rolf did a fine thing, to
distribute demo’s of JewelCAD (Gold Machinery, charged $50), so
that was a gift. You can go to or and
download a demo of Rhino3D. Try the tools, investigate what is
available and see if it is for you. There are many Old World,
classically trained jewelers, approaching the craft, with a new
perspective. The output is a different matter, you don’t have to
buy a machine, there are service agencies to make the model, for
you. See if it fits in to your production requirements and
schedule. Investigate the difference in a surface / solid modeler
and a CAM package. Then, you can decide what will work, for your
particular needs. Some packages are engineering based, others are
drawing based. Some learning curves are 3-6 months, others,
years. Have fun, try the demos and learn in the process.

Best Regards,

Christian Grunewald
Precision Modelmaking

For those on this forum who are interested in getting models
produced on a Sanders machine, contact Emil Vicale, he is