Fruit grinder

I'm planning to build a pedal powered fruit grinder and have a question with the drum.

What are the preferred types of drums? I've seen screws drilled into a round piece of wood that effectively scrap the fruit to pulp.

Are there other techniques? This is not a project I plan to spend much money so everything will come from recycled parts.

Thanks for some ideas!

What kind of fruit are you wanting to grind? A 1/2 hp or more garbage disposal works quite well for apples.

Yeah, I was thinking about that but electricity is a problem where the grinder will be located.

I went ahead and made a drum grinder with tilted screws but I'm afraid they're going to rust. Anyone have any ideas?

Stainless steel screws. The drum works good I have one and like it.

Im currently building a drum, after seeing several examples of the wood drum/stainless screw examples. I decided that I probably couldn't make a perfectly round wood drum, so I'm trying a 3inch dia PVC pipe. I bought two 3in threaded female adapters which i joined end to end with a regular piece of pvc pipe which i glued. so I ended up with a drum aprox 6 inches long with interior threads on either end. I then added a pipe cap on both end which I drilled a 3/4 in dia hole in each cap end. The axle was a little tricky I used a length of 3/4 in threaded rod but any metal rod would work. "I had it on hand so thats what i used" steel dowel rod would be better. I drilled a 1/4 hole in two spots along the length of the axle which will match two holes in the drum then they are connected to the drum via a couple 1/4 20 carriage bolts.
the cutting part of the drum consists of aluminum "L" bracket that I cut into 6 inch lengths, then I cut serrated "teeth" on one side of the bracket. then i attached the flat uncut side of the bracket onto the drum face with three or four self tapping one inch screws. It sounds complicated but I'll attach some pics when its done its really pretty simple and it looks truly wicked "something out of road warrior"