[rmachinist]

Hi,
Looking buy homing / limit switch for PM25-MV CNC mill there are so many anyone can recommend one / witch what one to buy

[Jim Dawson]

Most of these would work. Look for slow action rather than snap action. IP67 rating. https://www.automationdirect.com/adc...limit_switches

[awerby]

Non-contact optical switches are supposed to be more accurate than mechanical type switches. This is good when you're also using them for homing; for limits only it doesn't matter much: D5F High-precision Optical Switch/Features | OMRON Industrial Automation

[rmachinist]

Non-contact optical switches are supposed to be more accurate than mechanical type switches. This is good when you're also using them for homing; for limits only it doesn't matter much: D5F High-precision Optical Switch/Features | OMRON Industrial Automation

I wonder what if I was cutting steel and a chip hits the switch?

[CS900]

if you plan on using the switch for home switch as well you'll want something that repeats accuratly. I use these ones on my mill and lathe:

https://www.automationdirect.com/adc...racy)/css60b-l

they are a bit pricey, but they are IP65 rated and repeat to .0002". I've been using them for a few years now with no issues.

[dazp1976]

I've just taken a chance and ordered some cheap proximity sensors NPN-NO type to have a play with.
Prob take a week to turn up .
I bet they'll be crap and be a pita. (hopefully not!)

[Al_The_Man]

One thing to watch for with proximity version is that they can be tripped by stray chips etc.!
Al.

[CL_MotoTech]

I've posted my switches here a number of times. They repeat quite nicely (inside my backlash), despite being dirt cheap. Covering the switches and targets is recommended. On long runs where chip build up occurs and the coolant is pumping non stop chips tend to find their way into things that seem impossible to get to. If coolant is a thing on your mill, make sure to get these potted ones.

https://www.ebay.com/itm/10PCS-TL-Q5...UAAOSwYHxWMdIn

[joeavaerage]

Hi,

I use and prefer snap action microswitches for home switches, using these roller plunger switches I obtain 0.02mm repeatability
without index homing:

https://nz.element14.com/honeywell/b...ger/dp/1525198

They have hysteresis which is benficial for home switches.

Proximity switches are perfectly good for limits but the poorly defined hysteresis counts against them for home switches IMO.

Craig