Hello again all... I'm trying to configure a touch plate probe to work with my standard Ox build and Xpro v2 Cnc controller. I have hard limit switches set up on x,y & z. I think I know how to initiate the probing command g38.2 cmd... But where on earth do I wire the probe wires to on the Xpro? Typically it would be pin A5 on an arduino... Baffled!
Pin A5 is available on the Xpro. It is in the black header at the USB port end of the board. See pinouts here: https://raw.githubusercontent.com/Spark-Concepts/xPRO/master/wiki/IDC.JPG
Just FYI, I used exactly that pin on the xPro v2 for my own Z-axis touch plate. It works perfectly and has so far been completely reliable. Make sure to test in stages and have your hand over the emergency stop when you finally try it 'for real'. Also, it helps if to have a touch plate with a spring-loaded base so that you won't damage your tool if there is a problem with connecting. I use this gcode: G38.2 Z10 F30 This sets the speed to 30 mm/min, and stops at Z=10 if it doesn't contact the plate. But I would engage the emergency stop before it got to that point if I had to (my plate is 1" above the surface). I should note that my tool tip still gouges the spoilboard slightly. But I am not sure if this is because of flex in the machine, slight inaccuracy in my z-steps, or my pressure foot causing the machine to flex. But it isn't a big enough problem to stop me from carving at the moment. -Jonathon Duerig
Jonathon, Can you tell me what type of connector did you use to connect to the usb header? Also, what does your spring loaded touch plate look like?
I just used standard jumpers to connect to the pins on the board. Something like this: Pololu - Premium Jumper Wire 50-Piece Rainbow Assortment M-F 3" Then I plugged the other end into a barrel jack screw terminal that I fixed in place: Pololu - DC Barrel Jack to 2-Pin Terminal Block Adapter The touch plate I got was from CNC router parts. It is similar to this one: Auto Z and Corner Finding Touch Plate | CNCRouterParts I cut off the connector that came with it, stripped the leads, and then put them into a barrel plug screw terminal: Pololu - DC Barrel Plug to 2-Pin Terminal Block Adapter This gave me an easy way to plug/unplug things and put the touch plate away when I wasn't using it any more. I'm certain that you could easily replicate the spring touch plate pretty cheaply with a copper plate, a bit of solder, and some shoulder bolts and springs. Best of luck. -D
