Cad/cam - faq

Jewelry Discussion
1

Hi Jeffery,

Welcome back to Orchid! I consider you one of our “elder statesmen”,
so I’m glad you’re back to share your knowledge with us. Although,
it’s been a little while since we’ve been in touch by email, I
continue to learn from your occasional posts on the Rhino and
Flamingo newsgroups.

The CAD/CAM topic has been a little quiet lately, so it’s good that
you’ve opened it up again.

Several months ago, I volunteered to help develop a CAD/CAM FAQ page
on Orchid.

We got off to a good start, but I may have been a little grandiose
in my initial goals. As it happened, I met one of our members at the
Orchid dinner at the last MJSA show in NY, who lives in my vicinity.
We’ve been meeting and talking this summer to strategize a solid plan
to get the FAQ page rolling again. It’s part of GAP, the Ganoksin
Archive Project. There will be an annoucement regarding a new format
for the tree structure and a new call for volunteers. So, after a
period of dormancy, there will hopefully be some new activity, very
soon. Please feel free to join the project, if you wish.

Like yourself, I’m adjusting to an ever increasing workload in
conjunction with the ongoing challenge to stay abreast of emerging
developments in CAD/CAM technology. I’ve been really very fortunate
to have made a lot of great new friends through this work and I’m
very grateful to have received this opportunity to revitalize my
career as a working artisan. It all started when I stumbled upon the
Orchid List some four years ago. I hope never to forget that! :slight_smile:

Best regards,
Jesse Kaufman
West Hartford, CT

CAD/CAM Technology
Handcrafted Originality
www.jdkjewelry.com

2

Hi Jesse

I’d like to help out a little with the FAQ, sounds like a wonderful
idea. Do you know how many people here use CAD for design, and CAM or
Rapid Prototyping for modeling? Maybe all those interesting could
chime in with a Hello… :slight_smile:

Jeffrey Everett

3

I started to look into rapid prototyping a while back, but it
started looking like a rather sizable investment. I’m still
interested, but not willing to sink 30-50 thousand into the project.
I’m well armed with more than enough PCs and adequate knowledge to
handle the learning curve, but the dollars sure made me choke. It
cant be as expensive as I found at that time,is it? Ed

4

I bought Model Master’s Art To Part system over 4 years ago and was a
worthwhile investment. Sherline has begun offering a complete CNC
mill with a dedicated Linux computer at a very affordable price
(compared to my system). Joe Martin has put a lot of effort into
developing his own system, people have been modifying his machines for
years. There is a learning curve with any new hardware/software
system, you just have to decide if it will work for you. My background
includes a stint as a modelmaker/designer for a RI jewelry house in
the 70’s, I had been looking for a rapid prototyping system, and
ArtCAM and the milling machine have been a great addition to my
tooling. It is not an end-all situation, you still need a sense of
design, and a solid background in metal working techniques, and common
sense around machine tools.

Rick Hamilton

5

Hi Jeffrey, We use Cad/cam with a few mills we made and primarily do
jewelry models for our casting customers. Our specialty is corporate
logo’s, pins.pendants… we are just getting our feet wet with a 4th
axis system we built last year and had no time to try it.

Daniel Grandi Racecar Jewlery Co. Inc. Tel: 401-461-7803

6 
    I started to look into rapid prototyping a while back, but it
started looking like a rather sizable investment. I'm still
interested, but not willing to sink 30-50 thousand into the
project. I'm well armed with more than enough PCs and adequate
knowledge to handle the learning curve, but the dollars sure made
me choke. It cant be as expensive as I found at that time,is it? Ed

[While you can certainly still spend that much or more, it doesn’t
have to be that expensive. Especially if you’re willing to consider
what Roland calls “Subtractive Rapid Prototyping” (CNC milling), you
might be pleasantly surprised. The additive machines (using
techinques like stereolithography, Fused Deposition Modeling, and
Laminated Object Manufacturing) are still pricy, but you can get all
the software and hardware to scan actual parts, design parts from
scratch, convert them to toolpaths, and cut them out of solid
material (like machinable wax) using CNC (Computer Numeric
Controlled) milling for a lot less. The Roland MDX-15, which scans in
3d and mills too, costs under $3000, and comes with all the software
you need to capture parts, convert them to 3d models, and fit
toolpaths to them. I’d suggest getting Rhino as well, so you’d have
modelling capability, but your total tab would still be well under
$5k, including a computer, tooling and everything you’d need to start
making jewelry-scale parts.]

Andrew Werby

7

You don’t have to put out tens of thousands of dollars for a complete
CAD/CAM system. I have a Taig Micro Mill with 4th axis and Rhyno-3D,
Bob Cad, and Micro Proto for software. The whole works was a lot less
than $10,000 U.S. There’s a learning curve to mastering Rhyno but I
was able to put the system to use almost immediately. I could not
live without the system now. I’ve been blown away with what I’ve been
able to accomplish with this machine during the last year and a
half. It’s a rugged, compact, precise little marvel. Robert Hood

8

Please add me to the list of those willing to add to the FAQ. I
have a desktop New Hermes computerized engraving system with a 4th
axis. I have their software and I am learning to use MasterCam,
Solidworks and Rhino.

Charles Friedman DDS
Atlanta

9

For you people interested in RP, Milling, etc., instead of buying
this equipment why don’t you consider using a contract shop before
spending all that money on equipment. The way technology is changing
you’d be better off sending the file to a shop & letting them grow or
mill the site for you, at least in the initial stages. If you want to
get into that equipment (I don’t own any but know people who do),
plan on more than just the equipment cost. Among other things to
consider are your skill levels, training another employee to run
that equipment if you don’t, what happens when that employee leaves
to work for the jeweler down the street who is willing to pay more
than you, how often will you really need that equipment instead of
carving it yourself by hand (you do know how to carve don’t you?)

Just some food for thought.

Scott Lewis
Pat Lewis Designs

10 
    For you people interested in RP, Milling, etc., instead of
buying this equipment why don't you consider using a contract shop
you'd be better off sending the file to a shop & letting them grow
or mill the site for you

Scott or anyone, I have hundreds of things i made that i would like
to have symmetrical opposites(rough) of, CAM must be great for
making or roughing symmetrical opposites of 2 or 3d carvings or
objects, for earrings, yes?? I could see that saving alot of
time.(FTC ALERT)

Do many people rough out complex 3d design shapes in wax, with CAM,
and then handcarve to the finish??

And refering to scotts’s statement, how much would it cost to get a
maple leaf, 1x1", 1/8" thick, or even a cube, 1x1x1, hollow inside,
with all sides(or 5) represented as pierced grids or bar patterns??dp

11 
Scott or anyone,, I have hundreds of things i made that i would
like to have symmetrical opposites(rough) of,, CAM must be great
for making or roughing symmetrical opposites of 2 or 3d carvings or
objects, for earrings,, yes?? I could see that saving alot of
time.(FTC ALERT) Do many people rough out complex 3d design shapes
in wax, with CAM, and then handcarve to the finish?? And refering to
scotts's statement,, how much would it cost to get a maple leaf,
1x1", 1/8" thick, or even a cube, 1x1x1, hollow inside, with all
sides(or 5) represented as pierced grids or bar patterns??dp

Once a CAD model file is accomplished, the creation of opposites is
produced using the ‘mirror’ command, about 3 seconds work!

In order to make mirror opposites from your existing pieces via CAD
would require the re-creation of the original models in CAD first, at
least in respect to being ‘exact’ opposites. Perhaps some of the
pieces could be 3D scanned, but there are many factors to consider,
such as shrinkage, finishing, etc.

I personally try to avoid hand carving totally when designing with
the aid of a computer. One can simply not carve to the accuracy of a
CAD model. At times though I machine some components of a piece and
hand carve the rest. However, I feel compelled to say that achieving
a hand carved look in a CAD model can be extremely difficult at
times. CAD, is simply another tool, like a saw or file, and requires
substantial practice to master, or to even mimic what the hands can
find easy to do. CAD models have a certain use, as does hand carving.
For instance, it is highly unlikely that machining can ever replace
artistic hand engraving.

A Maple Leaf, for instance, is struck from a steel die that has had
much finishing, a rather lengthy and exacting process. Yes, it can be
done, and I do commerative coins and have some experience with
coining, but would not consider making a Maple Leaf. Substantial
equipment and time is needed to take a coining job from start to
finish, i.e., the CAD or tracing model, the engraving of the die,
finishing/polishing of the steel die, the making of the planchette
(blank gold slug), the die set and coining ring, the 300 ton press,
etc, etc, etc) A huge process…

A one inch hollow cube formed of pierced sides must either be
fabricated (possibly from machined components) or 3D printed (Rapid
Prototyping), and in certain unlikely cases can be machined as one
piece. My specialty is no longer exclusively milling, but production
of prototypes from 3D wax printing (see the process at
www.solid-scape.com)

Jeffrey Everett

12

dp, Using cad/cam wax machining makes carving a mirror image copy
very easy (and accurate!) BUT, creating the CAD model for the
original wax is THE expensive part of the process. Additional uses
of a model, whether as proportioned ladies and gents rings or a left
and right, makes the initial time investment much more reasonable. In
regards to roughing complex designs, I prefer that the model is as
detailed and complete as I can mill. (And they also have to be
complex enough to warrant a process a lot more complicated than hand
carving.) Wax finishing is mainly smoothing tool marks, and doing
undercuts and backside hollowing when easier done by hand than trying
to mill. Really fine details get reworked in metal, a graver is
capable of finer work than a rotating tool.

In regards to pricing, much depends on the details...for your maple

leaf are you providing a jpg or a complete 3D model? Does it have one
or two sides? Does your cube have identical faces (ie. possibly a
single milling job repeated) or will it require two setups to mill
the 6 surfaces? An accurate quote depends on detailed information
about what you expect, but you are looking to be starting at around
$100. A more complex and detailed models don’t cost a lot of my time
but that 2 setup, 4 axis cube milling job sure would.

Jeff

13 
     Do many people rough out complex 3d design shapes in wax, with
CAM, and then handcarve to the finish?? And refering to scotts's
statement,, how much would it cost to get a maple leaf, 1x1", 1/8"
thick, or even a cube, 1x1x1, hollow inside, with all sides(or 5)
represented as pierced grids or bar patterns?

I totally agree with Jeffery’s statement “I personally try to avoid
hand carving totally when designing with the aid of a computer”.

Hand carving a milled model, sort of defeats the whole purpose of
doing it in CAD. May I ask, why would you not want to either do the
whole thing by CAD or else do it exclusively by hand? You could just
carve the model by hand to begin with, and then silicon mold it and
shooting a number of waxes, which could be hand carve with
individual design motifs. As Jeffery also points out, hand carving and
milling, each have unique merits and preferred applications. The only
advantage I can think of for designing and milling a leaf model with
CAD/CAM and then carving it up afterwards, might be in the case
where the design includes a pattern of bezels, or other complex stone
setting arrangements which also needed to be perfectly matched into
left and right pairs. Then it might make sense to first create the
leaves with CAD and then do your hand carving of selected areas with
a individualized pattern of veins on a 2nd generation wax. You’d also
have to compensate in the scale and dimensions of the design to
account for all the molding, casting and finishing variables.

While it’s possible to create a handcarved look in a surface modeler
such as Rhino, it’s not always practical in terms of time and effort.
A program like ArtCAM tends to be more intuitive and much quicker in
terms of creating naturalistic looking organic shapes such as leaves.
In the ArtCAM in Action, signmakers section ( http://www.artcam.com
) there is a cool project featuring grape leaves. The same thing
could be done on a much smaller jewelry scale, including the creation
of metal molds for plastic injection.

Sometimes a very complex design can be generated directly from a
carefully edited grayscale bitmap imported into ArtCAM. There are
some fantastic examples of this in the ArtCAM users gallery showcase.
One artist recently posted some images of portraiture medallions. He
uses a combination of Photoshop, Corel Draw and ArtCAM.
http://forum.artcam.com/ Hope this helps.

Jesse

14

It seems to be that eventually I will read a post in a thread that
just forces me to respond, even when I thought I would stay out of
it. One of the most important things I have learned on this forum is
not to presume I know better than someone else what is right for
them. If I could afford to be in the CAD/CAM fray, I would use it as
a design tool, and not go into prototyping. The appeal, for me, of
the computer is that I can sit down with a customer and provide them
with a better rendering of what their piece will look like. I just
can’t draw well, and don’t really have a great desire to learn at
this point. There is so much more that I DO want to learn that I
just can’t seem to make the time (or effort). Another appeal is being
able to make changes to a design almost instantly rather than having
to physically erase and redraw, or start fresh for each change. For
me, the computer becomes a tool of communication. It isn’t important
to me to have the precision prototyping available for my current use.
Perhaps in the future??? Moot point anyway, can’t afford the CAD
right now, either. Jim

15 
   If I could afford to be in the CAD/CAM fray, I would use it as a
design tool, and not go into prototyping.

Why not? The file just needs at this point to be sent to a 3D
printer to produce a wax, plastic or even metal model? The price
starts at aroung $65 for most of the models that I do. I have even
drawn sprues and had trees of thirty models or so done for around
$100. These models are not nearly so subject to warpage as happens
with rubber molds.

    The appeal, for me, of the computer is that I can sit down with
a customer and provide them with a better rendering of what their
piece will look like.

I do the same thing, and over the course of a week or so can email
views until they have what they want.

    I just can't draw well, and don't really have a great desire to
learn at this point.

I can’t draw at all. After close to a decade on the bench, I finally
found retail designers that could, and it seemed to me at the time to
be a long awaited answer to the previous decades problems. Working
from decent drawings put both the end client and myself on the same
page.

     Perhaps in the future????  Moot point anyway, can't afford
the CAD right now, either.

It’s a whole lot cheaper that a new laser. I might think about a
laser when they get down to $3,000. Furthermore, this business is in
flux. Change is happening far faster than I could have imagined 20
years ago.

Bruce D. Holmgrain
JA Certified Master Bench Jeweler
http://www.goldwerx.com

16 
     <snip> Moot point anyway, can't afford the CAD right now,
either.

Maybe you’re selling yourself short, Jim. While there certainly are
some expensive CAD (Computer-Aided Design) programs out there,
especially if you’re looking at customized jeweler’s versions, you
can also find some for little or no money. You can start with 2d and
move up to 3d. Just being able to print out an accurately scaled-down
drawing can be very helpful for laying out a jewelry piece. Also,
drawing freehand and drawing on a computer are very different. Many
people who think they can’t draw find that it’s a lot easier when a
straight line is automatically stretched between any two points, or a
curve can be manipulated by pulling points until it’s right. If
you’re used to struggling to get one side of a piece symmetrical
with the other, you’ll find the “mirror” function very useful.

CAM (Computer-Aided Machining) doesn’t have to be nearly as
expensive as people here seem to think. Although it’s possible to
spend quite a lot of money on it, there are some very capable systems
available in the $2k-$4k range.

Andrew Werby

17 
Do many people rough out complex 3d design shapes in wax, with CAM,
and then handcarve to the finish??

This is something that I do quite often.

I do a lot of pieces that are adaptations of drawings. In the past,
I have often found it frustrating to keep track of the guide lines
that I had drawn on the surface of the wax as I carved down into the
wax block. When our company purchased a CAD/CAM system, I found that
it was useful to make a rough 3d model in Rhino using the vectors
from a scan of the drawing. I usually make simple models of the
body, limbs, and head. This allows me to experiment with the
placement of the separate parts. Then I transfer it to ArtCAM for
blending the separate parts, shelling the result (essentially
hollowing out the back), putting in quality marks and signatures and
then generating the toolpaths. Once the piece is carved, I can
easily add in details like cross-hatching and facial features in the
wax or later on in the casting.

Being able to manipulate the various parts of a model in 3d space
really helped me with the creation of the following model:

http://www.lovethatcat.com/images/dangling-cat-necklace.jpg

On this piece, it was important that the chain passed through the
legs of the cat so that it wouldn’t bind. I was able to move and
bend the separate limb models around in Rhino until I got the proper
clearance for the chain. This probably would have taken a few
attempts to get it right if I was hand-carving it out in wax. The
piece has Edward Gorey’s signature on the back, and that was easily
done in ArtCAM. In the old days, we would have sent that kind of
work out to an engraver, adding another 7-14 days to the creation of
the model.

Here are some more examples of work that used the combination of
CAD/CAM work and hand work. The bats, the ballerinas and the “cat on
a unicycle” were all done this way. The others on this page were
done by hand before we purchased our CAD/CAM system.

http://goreydetails.net/search.php?category=21

I’d like to add that we are not affiliated to the companies that
these links lead to.

Thanks,
Tom Murray
DVB, inc