High Precision Homing Switch

[JohnHaine]

Chaz, I have made something based on the "touch plate" concept used for mill Z homing.

(I hope that works!)
Repeatability seems to be better than 10 microns, and in conjunction with my tool setter on my first trial of homing/applying set tool offset/turning I achieved indicated microm accuracy on diameter. This cost nothing to make, it's essentially a bit of PCB laminated on to 6mm of tufnol superglued to the apron front. Obviously there are issues of wear and tarnishing so I intend to upgrade it with one where the contact surface is beryllium copper.

[Chaz]

Chaz, I have made something based on the "touch plate" concept used for mill Z homing.

(I hope that works!)
Repeatability seems to be better than 10 microns, and in conjunction with my tool setter on my first trial of homing/applying set tool offset/turning I achieved indicated microm accuracy on diameter. This cost nothing to make, it's essentially a bit of PCB laminated on to 6mm of tufnol superglued to the apron front. Obviously there are issues of wear and tarnishing so I intend to upgrade it with one where the contact surface is beryllium copper.

Thanks, I had though of similar - this is the way that we deal with milling offsets, so no reason why it wont work on a Lathe. Ill try the switch from audioandy (Thank you) first and go from there.

Thanks for the other suggestion Gary.

[audioandy]

Hi Chaz

Switch posted today first class so should be with you tomorrow.

Regards
Andy

[Chaz]

Hi Chaz

Switch posted today first class so should be with you tomorrow.

Regards
Andy

Thanks, appreciated.

I retested my cheap proximity switch with a 'semi decent' analog DTI and it was surprisingly accurate. My el cheapo electronic DTI seems not to be repeatable. Go figure ...

I also managed to get my spindle speed / encoder setup to work and tweaked my steps for X and Z, explains why I was getting inaccurate cuts, not out my much, but it was out.

Ill still try the mechanical switch - just need to figure how to mount it with my setup.

[Chaz]

Hi Chaz

Switch posted today first class so should be with you tomorrow.

Regards
Andy

Received, with thanks.

[audioandy]