[TheForge] Tungsten

[Ralph Sproul]

	I also have a question - it is not related to forge contruction or burner
placement though I am enjoying the posts on them.

	Does anyone have a source for 3/4, 7/8, or 1" round Tungsten.  From my
readings on the net it is a "refractory metal" that is used in shaping and
steel working process as it's melting temperature is almost twice that of
steel.  It is also impossible to weld for the small shop, but is made in
sintered powder pressure process to make it machinable and useful to the
metals industry(and others).  It not only has a high melting point - but
also a high compression value so it can be used as a slitting/drifting
chisel in a press like Uri Hoffi does in one pass thru a hammer head.
	The problem becomes finding which alloy to order and at a price one can
afford.   I was going to order from McMaster Carr - their high density
tungsten bar (8 inches of 3/4" for $97 - but the new price increase has it
at $151 for the product)   :-(
	From talking with Uri a couple years ago and Dean Curfman at Quad state,
They mentioned using an almost pure alloy of tungsten for hot punching.  The
high density alloy from McMaster is 90% tungsten and the rest is copper and
nickle - the copper making it stronger to hold shape.  The sad part is the
price of this material and was wondering if anyone knew where to access this
product more affordably.

	My question is: Does anyone have any input on which alloy of tungsten is
best suited for hot work slit/drift work? and does anyone know of a good
source to purchase this material where each chisel won't cost $151 ??

	.....not that this product could not pay for itself over time if it
worked - but I'd hate to experiment at that price.

	Steve Smith and I have been having a discussion on this and Steve sent me
this site with an overview on the refractory metals which is a good read if
your interested in this topic.  Would love to hear from anyone who's had
experience in tungsten alloys for hot work.
	Here's a nice overview on properties:
http://www.mpif.org/DesignCenter/refractory.pdf

Ralph Sproul
Bear Hill Blacksmith
Webster, NH

 http://www.bearhillblacksmith.com