Re: [CAD_CAM_EDM_DRO] Tool changing?

Chris Baugher wrote:

>Hi,
>I finally got my micro-mill converted to NC, and now I'm moving on to the
>programming part. It looks like the general strategy is to do a roughing
>pass and then a finish pass with a different tool. So my question is, how
>do you keep the Z axis alignment when switching to a different length
>cutter? I know about offsets in the program, but what about on the
>machine? My machine has a MT2 spindle and I'm using collets to hold the
>cutters. Do I need to make stop collars or something for each cutter?
>
>

Collets generally can't position tools precisely. The problem is
that very narrow tapers like the Morse can be moved a few thousandths
just by cranking on the drawbar.

I made a facsimile of my Bridgeport's R-8 socket taper that sat on a surface
plate like a cylindrical square. I can put various endmill holders and
arbors in it, and use a vernier height gauge to measure the tool length.
This works just like a tool presetter used with CNC machines with
toolchangers. I have some info and pictures at
http://jelinux.pico-systems.com/preset.html

Of course, if you can't get end mill holders for the MT2 spindle, you
have a problem.

Jon