Update 2021-10-22 - Added fake nozzle for 1/4" mills Update 2019-09-17 - Added a fake nozzle that slips on my 1/8" fluted mills. I find it easier to pop on and off.

I cobbled together a working bed probe for my low rider.. there are two options for probes included.. one fakes a printer nozzle you can put in a 1/4" collet and the other is a fake printer nozzle you can snap on the bottom of the low rider carriage. The snap on one is much better and you have no danger of breaking off plastic inside your router.

You will also need a pressure disc .. I got one for less than $2 here: https://www.aliexpress.com/item/32933920350.html these have a foam mount and just press onto the fake printer nozzle.

I wired it in parallel with my Z endstop, then enabled EEPROM and ABL bed levelling in my firmware.

To probe the bed I use a command like this:

G29 L100 R1100 F300 B2400

Where the numbers are the area to probe on the stock.

I find it works best zeroing out my machine then before I cut, probe the dimensions you are about to cut (if you use cnc.js you can see the dimensions on the preview window).

You can go ahead and start using the bed leveling like that, or if you want to visualize the data you can copy and paste it into the included spreadsheet (requires excel).

This is also useful for physically levelling.. shim your carriage so it's X direction is level with the spoil board then use the sensor to map all the low spots. I shimmed my low spots with a glue stick and sheets of paper under the spoil board.

Category: Machine Tools