[Jewelry making - Article 00835] - Re: [Orchid] Investment cast and torch

[John Donivan]

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


    There was another very interesting comment on this thread about
    silicates and carbon, too.  The real point, I think, is that we live
    in the real world, not a theoretical one.  If one could melt platinum
    in a vacuum (do-able), not touching anything else, suspended in "the
    ether" (not), with electrical heat, it would be perfect every time. 
    But we, at the bench, need to do it for real, and the metal has to be
    in, or on Something, and electrical heat is impractical at the bench. 
    I use a porcelain "Platinum" crucible - melt in the side-grooves to
    get more of an ingot.  A charcoal block will trash your metal, and
    burn to a crisp, too.  Oxy-Acetylene is, above all, the hottest flame
    we can get, in practice, and I use all the O2 I can get without
    blowing the flame out - hissing, bright blue cone.  It's fast
    (because slow melting is not good for metal, either), and clean
    enough for practical purposes. 

    A comment to students Re:  Which torch?  Again, distilled to the
    essentials, there are only a few-acetylene/air, oxy/acet.,
    air/propane, etc.  Just to stress- don't be confused by Brand-Names,
    The first choice is what "Type", and then pick a cost/handle/gas/regulator combo.


____________________________________________________________________
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
____________________________________________________________________