[yso191]

I want to use an old Better Bottle carboy for a hopper on my new JSP grain mill.  Has anyone had any luck or have any advice on this? 

Honestly at this point I think I'd shred it if I tried cutting it with anything I have.  My best guess is to use a torch to cut the bottom off.

[Stevie]

My first thought is a dremel. Wrap a length of masking tape along where you want to cut and use a cutting disk. I'm sure a few passes with a very sharp razor blade would do fine as well

[klickitat jim]

+1 on using a small thin cutting wheel. Knives or reciprocating will likely not work well. I did a bunch of plastic cutting when I built that greenhouse. Its easy to shatter

[erockrph]

A dremel might work, but I think a coping saw with a fine-toothed blade might be your best bet. Something like you'd get at an art supply store for cutting foam.

[piszkiewiczp]

I've never done this, but in principle some NiChrome wire, DC transformer, good ventilation and spare hardware to hold everything snug should melt right through the plastic and leave a relatively smooth edge.

[Scot (one T)]

+1 to the Dremel tool.   I've used one with a thin cutting wheel many times to cut plastic.  Works great.

[Werks21]

I also vote Dremel. They make a plastic cutting accessories so if you are willing to drop a couple of bucks you can have a purpose built plastic cutter on hand for years to come. The one I have is a metal wheel with teeth around the wheel. Cuts smooth and fast.

[yso191]

Thanks to everyone.  I think I'll give the dremel tool a shot.  Now I just need to find out who I lent mine to.

[Stevie]

If you have a harbor freight nearby. http://m.harborfreight.com/80-piece-rotary-tool-kit-97626.html

Low quality, but it's done a few jobs for me.

[ranchovillabrew]

I used a coping saw

[yso191]

I used a coping saw

How did it work?

[ranchovillabrew]

Easy. I filed down the edge a bit

[yso191]

Well good!  If I can't find who has my dremel, a coping saw is cheaper.

[Stevie]

I do like the nichrome method. But then again, any method having to do with melting, exploding or burning is always preferred.

[dak0415]

I want to use an old Better Bottle carboy for a hopper on my new JSP grain mill.  Has anyone had any luck or have any advice on this? 

Honestly at this point I think I'd shred it if I tried cutting it with anything I have.  My best guess is to use a torch to cut the bottom off.

Do you have a table saw?  Just set the blade to 1/16" depth and rotate the bottom of the BB against the guide.