[tjd10684]

i just got a nm-145 this is my first cnc machine and i dont want to blow another couple thousand dollars on a quick change system just yet. is their any way to execute a tool change using collets and have the part come out right? in other words can i re zero the Z in the middle of a program during a tool change?

[ger21]

Something like this?
[nomedia="http://www.youtube.com/watch?v=7np99wSr9c8"]YouTube - Mach3 2010 Auto-Zero[/nomedia]

[tjd10684]

not quite. say i have a .75x.75x1" peice of aluminum and i want to machine a dome on top of it. my first set of code calls for a 1/2" roughing end mill to get the rough shape. my finishing step is using a 1/4" ball end mill. i dont have end mill holders or a quick change tool set i have to change the tool by removing the collet and end mill and replacing it with another. inside the collet their is nothing to set the tool height just a regular R8 collet. in this case can i during the stop for the tool change some way rezero for this tool.

[ger21]

Yes, that's what I'm doing in the video. It's a macro that zero's the initial tool to the workpiece, and also gets the location of a reference plate. After changing the tool, the new tool uses the reference plate to get the same zero position as the original tool.
http://www.cnczone.com/forums/mach_w...r_big-tex.html

[tjd10684]

thanks ill look again. this is all pretty new to me.

[ErnieD]

Go to Tormach's web site Home | Tormach | We provide personal small CNC machines, CNC tooling, and many more CNC items and look at their TTS line of tool holders. These have a shoulder that butts up against the bottom of the spindle so that the tool locates in the Z plane almost exactly each time you change tools.

Ernie