Any one ever built a milling machine for cutting mild steel? Any builds on here?

[Apples]

Any one ever built a milling machine for cutting mild steel? Any builds on here?

I see a lot a builds for aluminium cutting and plastics etc. But are there any DIY machines that have been specifically designed to cut mild steel?

I'd like to see some....

[thackman]

Have you seen this site. He does his test cuts in aluminum but the mill was designed from the ground up to be an improvement over many of the retro fits that you see here.

http://www.5bears.com/cnc.htm

Aluminum requires less power to cut and therefore less stiffness. Aluminum can also be cut at higher speeds. If you cut it fast enough dynamic stiffness starts to take over. All around it's easier to build a mill for aluminum.

Cutting steel is on the opposite end of the scale and it simply takes a lot of mass to provide the damping and stiffness required and there are few options available for someone in a home shop to build the structural components to the level of precision needed and avoid issues w/ built up internal stresses. It has been done but at that point it's usually easier to buy an old machine that someone else considers just an old hunk of iron and rebuild it as it would to try and fabricate and stress relieve/season a massive 1000lb+ weldment or casting made in the home shop.

[thackman]

I forgot to mention that epoxy granite seems to be an option that many consider promising but I've only seen a few try.

http://www.cnccookbook.com/CCMillCNCHome.html

[rowbare]

Here is a nice build by a very talented guy: http://www.cnczone.com/forums/showthread.php?t=30262

bob