I've had a quick go at saltwater etching (it sounded safer than acid etching to me, and had materials available). It works fine with Aluminium.
I don't have a saberforge saber, mine was just made from Aluminium tubing and a few other bits I had and I probably wouldn't have dared to ruin a saberforge hilt, but now that I've tried it I definitely plan to use this method again on my next home made saber.
DSCF5143 by
Stew750, on Flickr
Do a google search for "saltwater etching" and you'll find a few different variations on how to do it. more specifically search for "ARKM's saltwater etching tutorial" - thats pretty much the method i used, only I used a more simple way of masking and leaving the bare metal to etch. (I covered the metal in vinyl tape and cut the pattern out).