Pellets Cutter

sorry if this is already covered but i can really find it…  nor get my head around it.

So my goal is to end up with pellets, not flakes. The pellets doesnt need to be perfect.
By pellets i mean 3-5mm cylindrical shapes.

What ive been drawing on is:

1. First shred plastic in shredder.
2. Wash shredded plastic (as flakes)  in ultrasound washer
3.  Feed flakes in to extruder
4. In the end of the extruder have a rotating blade which cuts the plastic in to smaller cylindric shapes.

Is this the best way of doing it, are there any other better ways to do it?

If this is the solution, would the plastic have to be cooled down before cut in to smaller bits?  How to cool it, by fans or by water bath?


More or less, yes. Unless somebody has a better idea 🙂 I would use water bath as in filament production. Fans are probably fine too but loud and they consume energy. Other than that you could try a die with 2 or even 3 holes btw.
The winder pulley can also forward it to the cutter at the same time btw. You can use a 3d printer extruder motor (easy to control with an arduino – i still have code for that) to pull it through the cutter hole.
Someone made some day a winder. Here are the plans.
Keep us posted; that came up a few times.

Thanks for the reply, great idea with the winder/pulley.

I assume the cutter needs to be close to the pulley where the plastic exits?
My idea would be to have a a couple of blades rotating  close to the pulley/ similar to a food processor which cuts the extruded plastic.

Will keep you updated.