[TheForge] Re: Chip forge

[Michael Horgan]

Well, I used the fluidized bed technique a while back when doing some 
lost foam casting.I just bent a piece of copper tube into a spiral, 
pinched the end, drilled lots of holes on the top face, and set it 
into the bottom of a bucket. Added dry sand and run the air pressure 
up till it's like quicksand. About 90 psi in my setup for a 5 gallon 
bucket. It's easy to push a piece of styrofoam in, then when you turn 
off the air, everything settles in and locks down. Then just poured 
in the molten aluminum, replacing the foam with metal.  Works a 
treat, but puts lots of sand in the air.  Don't even want to think of 
red hot sand in the air...  Take a lot of fuel to heat the high 
pressure/high volume air.  Probably not a good technique for the 
backyard smith.

At 02:01 PM 3/4/2006, you wrote:
>Okay, I should start thinking these things through a little before 
>making comments.
>
>On further thought a fluidized bed shouldn't really be all that hard 
>to make work. I don't know how practical it would be as this idea 
>might damage work in the bed.
>
>So, how do you fluidize a bed? You force something through it at the 
>media's terminal velocity right? In the case of a fluidized heating 
>furnace it's the terminal velocity of the "chips" in burning 
>gas/air. In the case of certain gold extraction devices it's the 
>velocity of water/chemical mix through crushed gold bearing ore.
>
>Same principle at work and sin use for a LONG time.

Michael D. Horgan , lughaid at earthlink.net
http://members.aol.com/lughaid/
posting from
  A BRAZEN FORGERY
Blacksmithing and Metalwork
Claremont, Ca.