I just use an old cheese grater. (Now that we're vegan, we don't use it for anything else. <img alt="" class="inlineimg" src="http://www.mothering.com/discussions/images/smilies/lol.gif" style="border:0px solid;" title="lol"> )<br><br>
It's easier if you grate the short end of the bar.<br><br><br>
Just use a cheap hand grater- the kind that's meant for grating cheese or veggies. Just make sure to rinse it really, really well before using it for food, unless you're going to set one aside just for non-food use. Soapy pizza is NOT tasty! <img alt="" class="inlineimg" src="http://www.mothering.com/discussions/images/smilies/lol.gif" style="border:0px solid;" title="lol"><br><br>
You really don't need very much grated soap for a batch of laundry soap- it won't take that long to grate it by hand. IMO, it's not worth the effort to get out the food processor and clean it up afterwards, just for a little bit of soap.
I don't know if this would work in a regular blender, but I have a real powerful one and cut the bar into chunks and put it in there with the borax/washing soda. It came out awesome-like regular, fine powder!
I've got a little hand rotary grater that we use for cheese and such - something like that would probably be your best bet, rather than hand grating it on a stand grater or something.<br>
I can grate up an entire wedge of Romano from Costco in 30 minutes if I don't have "help." Grating it by hand would send me to the looney bin. Something similar's probably $10 (if that) at Bed Bath and Beyond, and I just throw all the pieces in the dishwasher when I'm done using it. <img alt="" class="inlineimg" src="http://www.mothering.com/discussions/images/smilies/smile.gif" style="border:0px solid;" title="smile">