[Source] Limit Home Switches For Mini Cnc

Without seeing your mechanical setup,it's hard to say but hall effect sensors are fairly sensitive. Some of the rare earth magnets are quite strong. A 1/4" diameter magnet embedded in a pulley should be sufficient to trigger the sensor. You will want mount the sensor as close as possible to the magnet path for greatest sensitivity. Depending upon your design, you may be able mount a plate under your pulley stack to accommodate the magnet. You can find rectangular rare earth magnets on eBay as thin as 2mm.
 
this is not my pic but it's the exact setup I have
It looks like you could fit a cylindrical magnet in the center of your driven pulley. From the drive pulley, I assume that is where the set screw for the pulley is. A hole could be drilled and a small rare earth magnet epoxied in. Because your belt can be located on either side, you would want to mount the proximity detector on a hinged bracket so you can swing it out of the way to change the belt from an upper to a lower position or vice versa.
If you decide to go that route, check the sensitivity of your setup (separation distance) before you drill your pulley.
 
Back
Top