Steve McCarthy wrote:
Hi Jeffrey,
Thanks for the advise on stereo lithography.
I’m trying to understand the overall process of going from the design on
computer to finished piece. I think if you could step me through your
process I would get a foundation to proceed from.
This is exactly what I’m writing a book about, how to go from a design,
either hand or computer drawn to a finished piece of jewelry.
Let’s say you are creating a simple 2-D item, can you walk through the steps
that you take to get from design on computer to finished product?
A simple 2-D design, a flat backed object with a recessed area defining
design, lettering and the like, could be pierced out. I spent years
developing photopolymer techniques for producing 2-D patterns for
casting in metal. The process goes like this for photopolymers:
Once your computer assisted design is finished, you can do two thing
(1) print your drawing at about 400% and take it to a photo shop that
can reduce it 25% (for sharpness and smoothness) as a film negative.
(2) send your file via modem or hand deliver it to a service bureau than
can produce a film negative (usually Linotronic) at 2400 dpi which is
great for photopolymer etching.
Use the negative as a mask for generating the photopolymer pattern.
etc…
Elaborate
on the photopolymer process and its limitations. Could you also describe your
process for a 3-D item? I think you are using a metal mold process for 3-D
items and a photopolymer process for 2-D items, am I correct?
With photopolymer or magnesium printing media, you are limited to
(usually) a single etch depth, very fine detail is lost or very shallow
and disappears when finishing. Casting is much the same as with wax with
some fundemental differences. The photopolymer expands and boils and can
break down the investment, so you need an investment that will withstand
that. I suggest ringleww casting investment sold through dental
suppliers, you’ll need a solution that will dissolve the investment
caught in the details, I forget the name right now, your dental supplier
can tell you. The photopolymer can also be attacked by the steam
generated during the initial phases of the burnout process causing loss
of detail and other complications. I did some pretty amazing things with
photopolymers involving pierced-out lettering especially. Unfortunately,
I don’t have the time right now to get into an in-depth discussion.
Just for clarity, would you define a 2-D item?
See Above
Jeffrey Everett
Handmade 18K, 22K, and platinum gemstone fine jewelry.
Diamond setting, rubber/metal molds, casting, lapidary
Die and mold engraving, plastic patterns for casting.
Cad jewelry design, cad/cam milling scroll filigree…
P O Box 2057 Fairfield IA 52556 515-469-6250
You can check it ou at