[Jewelry making - Article 00373] - Re: [Orchid] CAD/CAM grown model woes

[Wayne Emery]

========[ Invite a Friend - http://www.ganoksin.com/invite.htm  ]========

Richard,

    The great advantage of the additive prototyping ("printing" or
    "growing") process is that a number of models can be "grown"
    simultaneously. That process can take as long as 12-15 hours,
    depending on complexity and number of models, but there can be great
    economy in doing so. However, using additive protoyping methods to
    grow single models is usually not cost or time-effective. 

    I worked with the technical team from 3D Systems when they were
    bringing their version of the technology to the jewelry market. It
    became obvious that casting problems had to be addressed. 

    To oversimplify (!), we discovered that great care had to be given
    to all stages of the casting process. Choice, handling and
    preparation of investment medium played an important part. Over the
    years, investments have become so "good" that many casters have
    knowingly or unknowingly taken "shortcuts" in their traditional
    casting routines. Unfortunately, the "idiot-proofing" features of
    many modern investing materials are no guarantee when it comes to
    burning out the various rsins and plastics used in the growing
    technology. 

    We concluded, at the time, that higher burnout temperatures and
    longer than "normal" dwell times were needed for the materials we
    were using at that time. This finding seems to be consistent across
    the board, still, as far as I know. 

    It was interesting to note that many users were looking for a "magic
    bullet" that would solve all their modeling needs. More bluntly,
    armed with this new hammer, every job began to take on the
    appearance of a nail, and with the usual results! Often, the best
    use of the growing machine is to not use it. 

    Now, the best solution to dealing with the near-ubiquitous ash is to
    blow it out of the hot investment with an air gun, then return the
    investment to the furnace for a minute or three to assure an even
    re-distribution of heat before casting. I know what you're thinking,
    but there has been no damage to the investment after doing this many
    thousands of times. Sounds crazy, but it works. 

Wayne Emery
____________________________________________________________________
T h e   O r c h i d   L i s t
Open Electronic Forum for Jewelry Manufacturing Methods and Procedures
____________________________________________________________________
Orchid FAQ:
~ http://www.ganoksin.com/orchid/faq.htm
Orchid Archives:
~ http://www.ganoksin.com/orchid/archive
Orchid Galleries:
~ http://www.ganoksin.com/orchid/gallery.htm
Invite a Friend:
~ http://www.ganoksin.com/invite.htm
____________________________________________________________________
Tips From The Jeweler's Bench - Article Archive
~ http://www.ganoksin.com/borisat/tip_sear.htm
The Jeweler's Selected Bibliography List
~ http://www.ganoksin.com/jewelry-books
Buy Orchid Jewelry:
~ http://www.ganoksin.com/shop
____________________________________________________________________
-Unsubscribe:
-Email: orchid-request AT ganoksin.com Body=unsubscribe subject=blank
____________________________________________________________________