Icenberg part 1: Building an ice cream machine

Turning a bearing surface directly onto the paddle so no metal parts from the axle will ever be in direct contact with the ice cream.
Standard

Prototyping a next level ice cream machine because.. ice cream!
First iteration with 1.33l container volume. Now searching for a leftover freezer/fridge from which I could upcycle the compressor and tubing.

In a further iteration I might design a proper spatula which can be mangled through CAD-CAM and then machined on the 3 axis CNC milling machine.

The outer container is face turned on the lathe to make a snug fit for a waterproofing cap.

The outer container is face turned on the lathe to make a snug fit for a waterproofing cap.

The polymer-rubber sandwich cuts like butter with sharp HSS tools.

The polymer-rubber sandwich cuts like butter with sharp HSS tools.

Turning a recess at the top cover, which will not be a fully closed lid. The fit was not good though and I turned another one out of wood for a first try.

Turning a recess at the top cover, which will not be a fully closed lid. The fit was not good though and I turned another one out of wood for a first try.

Due to the bad fit as a lid this piece was upcycled to a  handle.

Due to the bad fit as a lid this piece was upcycled to a handle.

POM (polyoxymethylene) cut to length on the horizontal band saw. Often used for medical equipment, this material is very well suited for any equipment which comes in touch with food.

POM (polyoxymethylene) cut to length on the horizontal band saw. Often used for medical equipment, this material is very well suited for any equipment which comes in touch with food.

Improvised fixture with some clamps. It's only a soft polymer after all.

Improvised fixture with some clamps. It’s only a soft polymer after all.

One of the most handy tools: the infamous one-hand clamp.

One of the most handy tools: the infamous one-hand clamp.

Ready for a pilot hole and a long bore operation.

Ready for a pilot hole and a long bore operation.

After reaming for a snug fit the hardened and ground axle was inserted.

After reaming for a snug fit the hardened and ground axle was inserted.

Milling the spatula.

Milling the spatula.

Wondering whether the resistance will still be too high to be turned if the ice cream starts to crystallize. Let's see.

Wondering whether the resistance will still be too high to be turned if the ice cream starts to crystallize. Let’s see.

M16 axle inserted into the spatula paddle and locked in place.

M16 axle inserted into the spatula paddle and locked in place.

Stock paddle on the lathe between two centers.

Stock paddle on the lathe between two centers.

Turning a bearing surface directly onto the paddle so no metal parts from the axle will ever be in direct contact with the ice cream.

Turning a bearing surface directly onto the paddle so no metal parts from the axle will ever be in direct contact with the ice cream.

Bottom cap with an oversized press fit turned out of Nylon (PA6).

Bottom cap with an oversized press fit turned out of Nylon (PA6).

Bottom cap on the lathe.

Bottom cap on the lathe.

Needs a few hits with a mallet - perfect fit.

Needs a few hits with a mallet – perfect fit.

The natural PA6 material is translucent.

The natural PA6 material is translucent.

Top lid from Multiplex wood, a fine plywood. Final piece will be out of POM.

Top lid from Multiplex wood, a fine plywood. Final piece will be out of POM.

Enough room for the copper windings from the compressor and/or a cooled fluid.

Enough room for the copper windings from the compressor and/or a cooled fluid.

First test with cooled salt water (1:2.42) at -21°C.

First test with cooled salt water (1:2.42) at -21°C.

The paddle withstands pretty much anything, but the resistance is too hard after a while. The efficiency is also lowered due to the work which is converted to heat in the ice cream after all. Next step is now to decrease the resistance further with more milled slots.

The paddle withstands pretty much anything, but the resistance is too hard after a while. The efficiency is also lowered due to the work which is converted to heat in the ice cream after all. Next step is now to decrease the resistance further with more milled slots.