Digital BW, The Print

I am sure this problem has been addressed before, but I am 
new here and haven't read everything on the site. I was printing 
on an Iris machine for a number of years before moving to Paris 
and having to leave my machine behind. Now I have an Epson 
1270 and am trying to print on Arches hotpress, at the moment, 
with standard epson inks. I have no trouble getting the correct 
tone in my B&W, but I can't get a clean edge. Is there a solution 
to this problem? My transform tables from the Iris will not 
translate to the Epson. Any suggestions would be greatly 
appreciated.
Kurt