Subject: Mokume

From: [email-masked] (RICHARD ALLAN JOHNSON)
Date: Fri, 19 Nov 1993 18:28:03 GMT

To all who don't know what Mokume is I will tell you what I am 
calling mokume.  I am forge welding brass and copper sheet together in my 
forge and them carving and filing for surface decoration.  Very similar to 
making damascus steel but much easier to weld.
	My problem is this. I would like to make some twisted patterns.  The 
problem is that when attempting to twist the welded (brazed) billet cold the 
welds delaminate and when attempting to twist them hot they delaminate 
either in the twisting process or in the subsequent flat forging process.  I 
know this is possible as I've seen twisted patterns in brass/copper mokume.  

Any help here would be mighty appreciated.

Rick

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From: [email-masked] (Mike Folenta)
Date: Fri, 19 Nov 1993 21:57:25 GMT

[email-masked] (RICHARD ALLAN JOHNSON) writes:
|> 	To all who don't know what Mokume is I will tell you what I am 
|> calling mokume.  I am forge welding brass and copper sheet together in my 
|> forge and them carving and filing for surface decoration.  Very similar to 
|> making damascus steel but much easier to weld.
|> 	My problem is this. I would like to make some twisted patterns.  The 
|> problem is that when attempting to twist the welded (brazed) billet cold the 
|> welds delaminate and when attempting to twist them hot they delaminate 
|> either in the twisting process or in the subsequent flat forging process.  I 
|> know this is possible as I've seen twisted patterns in brass/copper mokume.  
|> 
|> Any help here would be mighty appreciated.
|> 
|> Rick

     Well, if the layers delaminate when you twist them, then you really
 haven't welded/brazed them together.  You have just sort of mashed
 them together without actually joining the layers together at the molecular
 level.  Hence the layers just sort of peel apart or split when you twist
 or bend them.  You have to get the layers to -join- together, not just to
 be smashed close to one another.

     Most common cause that I know of is dirty layers.  This includes
 oxide contamination between the layers as you are heating and working them
 to try and join them.  The solution that I know of is to start with
 clean layers and then do all hot work in a reducing (definitely NOT an
 -oxidizing-) atmosphere.

     Or try and do all your hammer-forging in a pure nitrogen atmosphere...

     :-}  for the humor-impaired 

     It ain't as easy to hammer-forge/weld/braze stuff as you might think.
 In fact, it can be down-right tricky and a pain-in-the-#%$

-- 
       ***** These are my opinions.  Get your own. :-) *****
      Michael Folenta          | U.S. Army ARDEC
   Future Weapons Branch       | Picatinny Arsenal, NJ 07806-5000
  email [email-masked] | (201) 724-3791  [DSN 880-3791]

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From: [email-masked] (Terry Burkhardt)
Date: Thu, 25 Nov 1993 19:52:44 +0000

In article <[email-masked]>, [email-masked]

> Any help here would be mighty appreciated.

If you get delamination in brass copper mokume, it means your bonds are not
sufficiently strong. Try at least a four to one reduction in billet
thikness (hot) before timming edges. Then forge billet into rod. Do not
forge below a dull red heat. Billet should be able to be twisted either hot
or cold. Hint- billet is too hot if your brass layer beads.  
    
Phillip Baldwin
Shining Wave Metals
Snohomish, WA