Lathe, limit and home switches

[Transformer]

I am in the process of converting my Grizzly G0602 lathe to CNC. After watching some videos on the Mach3 site I think I will forget about home switches. A limit switch at the spindle end to prevent crashes would seem to be necessary, and probably one mounted on the tail stock as well.
And for the X axis, well probably limit switches are needed there as well to prevent winding the cross slide off the ball screw if I end up trying to move the cross slide beyond these limits.
Any comments on the need for these limit switches, mounting, type of switches and so on would be appreciated.

Dennis

 

[Bishop]

Hi Dennis

I put limit switches on my X2 mill conversion and wouldn't run a CNC machine without it, especially a lathe. You can set soft limits and home locations in Mach 3 but the physical limit switches are pretty much maditory I would think. I lever arm limit switches from Ebay, shipped from Hong Kong they cost a few dollars for 6-8 of them, i can't remember. Mounting was pretty basic, I just used some aluminium L bracket and tried to mount the switches where they would be clear of swarf etc.

Shawn

 

[Karl_T]

There are only two kinds of CNC machinists, those that have schmucked their machine. and those that haven't done it YET. A limit switch will save damage, cheap insurance. Now, I agree with you, you can get by fine without home switches.

I really like this project:
http://www.cnczone.com/forums/open-...01878-electronic-home-switches-made-easy.html

 

[Transformer]

Thanks for the input. I have now located and installed, but not yet hooked up limit switches for the Z axis. I am trying to figure out where to locate the X limit switches. While I struggle with this I thought I would ask your opinion on whether X limit switches are necessary or whether I can safely get away without them. (Maybe I am just being lazy here.)

Dennis

 

[Pmedic828]

After my son crashed the cutter into the lathe chuck, I made an "anti-crashing" fix using lever switches and mounting them on the saddle and on both sides of the cross slide - now when the saddle overextends, the roller lever switches drop off and open the circuit, causing the lathe to stop - a manual crank to get the switch re-engaged and power reset and everything is good to go without the cussing, fuming, and bad feelings toward my son - small price to pay to spend some quality time with him!