Hi Dave,
There are lots of ways of roller printing. David Walker from
Perth Australia came up with an interesting variation that
improves upon normal roller printing. In normal roller printing
the metal is indented. You make the die (the part with the
texture) out of highly calendared paper like index cards, manila
file cover etc (not Bristol board!). Then you indent it (as
described earlier in the thread) by using a pen, burnisher,
stamps, cutting, plain or fancy kids scissors onto the folded
paper die (like cutting snowflakes), paper punches, hammers,
burrs,roller printing lace or mesh or string etc into the paper
die first, anything you can think of. There is a relationship to
the brass method described by McCreight. The Walker innovation
was the use of a pusher paper to force the metal up into the
indentations and cut-outs in the hard paper, thus the metal has
raised details rather than indentations. I use 24g (.5mm) metal,
manila file cover. You set the mill to a dead pass (touching but
no pressure) on the mill and then use brown industrial paper
towel (others work-this is the best) folded six times, make a
sandwich with towel, metal and paper die (metal in the middle)
and run it through the mill. Metal thickness, paper towel type,
paper die material will determine the exact pressure you need. Do
a sample in copper first before you go to gold 
This gives you a very drawing like freedom on the metal surface.
Charles
Brain Press
Box 1624, Ste M, Calgary, Alberta, T2P 2L7, Canada
Tel: 403-263-3955 Fax: 403-283-9053 Email: @Charles_Lewton-Brain
Metals info download web site: Learning Center - Ganoksin Jewelry Making Community
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