3 Axis Foam Cutting Mill

3 - Axis Foam Cutting Mill - Part 16

Fine Tuning

Much like the lathe, I doubt that the mill will ever really be done, it will just continue to evolve.

Here is a 2 speed dremel tool that has replaced the original mill head. This unit runs at either 15,000 or 20,000 rpm, as opposed to the 2,000 rpm of previous unit.

Also the collet chuck accepts standard 1/8" cutting bits, and spins very true, again unlike it's predecessor. The NiCad battery pack has been removed and it's been wired into the 5VDC line off of the power supply.

This is a quantum improvement in the actual cutting bit, I haven't put the calipers on it yet, but the shank is 1/8th" and I would guess that the tip is just over 1/32nd" .

Originally this was a diamond encrusted grinding bit, but I've carefully ground and filed a clean flat surface on two sides of the bit.

The above bit is from this handsome set that I picked up from Princess Auto (a mecca for hackers like me...).

I fondled this set for over 5 minutes placing it in the basket, and then replacing it on the shelf a few times, agonizing over the $7.50 price tag... In the end I had hung them back on the hook and was about to tear myself away when I saw that they were marked down to $2.50, how could I resist

This is beyond my wildest expectations, little to no clean-up of the piece, crisp, true lines and flawless curves.

The pink foam is head & shoulders above the white beaded foam that I originally tried on the previous posting. So much so that when I burnt out paper trash today I disposed of all but one sheet of the white foam.

Here is the cast piece, with my hand polished finish.

There were no fancy wax dips, just foam straight into the sand and liquid metal.

The finish is a slow process that starts with a course rasp, 10" bastard file, 6" flat file, 150 grit sand paper, 220 grit, 400 grit dry and then wet and lastly 600 grit wet sanded.

The entire polishing process on this piece took over 2 hours.

In little over a week, I've made 3 plaques (including the one above), a custom Nova SS logo inside the Chevy Bowtie logo for a friend, totaling over 20 hours of machine time.

But the mill is not just for foam, here are a set of cylinder gaskets for a 1975 Suzuki 125 trail bike.

The original gaskets were scanned and converted to DXF format and converted to G-Code which feeds the mill.

The gasket material is fixed to a chunk of the remaining white foam that is similarly taped to the Y - Table.

This is a real bonus for me especially since I can't draw a straight line with a ruler. I didn't even look for a gasket set, considering that the bike is so old.

In closing I've gotten a better handle on the peculiarities of the G-Code converter (Ace Converter) and can move around very quickly within the DOS-based TurboCNC like it was 1986.

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