Hi,
I'm almost done with what i think is a reasonable design for a benchtop CNC mill. Bear in mind that i say that with no real idea what I'm talking about. I started off with an SX1 manual which i wanted to improve and the project, "grew legs" as they say.

My hope is if I post a few shots of the model and some general info you more experienced folk will be able to give me some tips / highlight the weak spots. I have taken note of the point that is often said that there is no replacement for mass so while this is a benchtop machine it will have to be a fairly solid bench.

To put some words to the pictures-

The column is 2 No SX3 columns which are 100 x 50 cast iron box with a 10mm wall - width over the two 270mm
The Gusset plates at the back are 10mm steel
The Z Risers are 100mm high 25 x 100 steel with a 25mm plate on top for the columns to fix to.

All the ways are linear slides all with 4 carriages
Z 42 x 10 THK, cant remember the model
X Hiwin 20mm
Z Hiwin 25mm

All Axis have Ballscrews
Z 1605 from CNC4you
X & Y 1204 probably from BST Motion

The Base is a cast iron Surface plate with a 25mm thick top plate

the belt drive is a DIY to give 2:1 up gearing and about 2:1 down. driven by a 500w BLDC sewing machine motor. which runs 200-5000 RPM

I hope to be able to cut steel, but have no particular speed in mind.

Solidworks puts the mass at C.142kg

The base is 24" x 18" and the Z is about 600 high.

Any questions or comments welcome

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Cheers,

Luke