Hi, I have build my Lowrider CNC and habe done the first test cuts. Its a little bid hard to find the exact 0 Point. Im using the Mini Rambo 1.3 and CNC.js. Is there a possebility to wire and use a Z Touch Plate?
Yes. I’m doing it.
You just get the Z-touch plate and plug it into two of the pins on the Z-min connector. If you’re using Ryan’s firmware, then the code is already in it to use it.
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(S) and (-). Don’t use (+)!
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I guess I got lucky
Ok cool.
Can I use xyz pad? Too null all axis
Or ist only with z axis posible?
Or should I buy this one?
The second one. The XYZ is not setup in the stock Marlin firmware at this time, from what I recall. Marlin is 3D printer as a core and is mostly concerned with getting bed height. Hence Z probing is supported. Probing material offsets for X and Y isn’t part of the game. Some folks use different firmware like GRBL to enable a probe like the first one you posted.
There is also a touchplate (like a little spatula) in the shop.
I am also wantIng to add a touch plate to my mpcnc, I got my board from Ryan so if I was to also get the second one pictured above do I need to change anything in the code to allow for the height of the probe?
Not in the firmware, but you would need to adjust for the height of the probe after probing.
You can see the gcode for the tiny touch plate:
Just change the value in the G92 Z<THICKNESS> command.
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Thanks for the advice, I have ordered a touch plate now, similar to the one in the second picture, apologies if my next question/s seem obvious but I have never played about with uploading from arduino to the mini rambo board. Is it just a case that I could plug my touch plate in to the Z min ports on the board and home the Z axis, once it hits the touch plate it stops and then I can just deduct the thickness of the touch plate to get my zero, or do I have to go in to the code in arduino, change the g92 z to say 20 (for a 20mm touchplate) and then press upload to the board. I have never ventured in to learning how to use/upload from arduino, I will do but that’s the reason for getting the board from Ryan because it was already done.
You don’t change the firmware on marlin (so mo arduino). You just need send a command to Marlin to subtract that height. That is the G92 command.
Do you have a computer attached? Or do you just use the LCD?
I use reptier with it.
Then you just send those G code commands in the console.
Alternatively, hone with the plate, move the Z axis down 0.5 mm. Then zero the Z.
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Yes. That too. Except it would be 20mm for your touchplate.
Be sure to measure the actual height of the one you get – mine was 19.3mm
Jeffeb3 thanks for all the advice. I have set my touch plate up and if I home the Z it works perfectly. Once I have done that I have used the g92 z20 in the manual control and sent it, The z axis then changes to -20 but the cutter doesn’t lower any further than when it touched the touch plate. Do I have to edit the actual g code before starting the job to include the first line of code for the g92 command or am I missing something completely easy and making this seem harder than it should be
It might be a problem with Repetier Host. It doesn’t like accepting the coordinates from Marlin, and keeps it’s own coordinates for jogging… I’m not sure how to fix that. I know there is a command @isathome to tell it that you are at 0,0,0, but that won’t help you at Z=20…
Can you move it lower by actually sending the G1 commands?
G1 Z5 F300 ; This should put it 5mm above the top of the worksurface.
And if that seems reasonable, then:
G1 Z0 F300 This should just tough the work surface.
I testet it out. Wired my touch plate to z-min S and -. If I move z down and then connect S and -, nothing happened. So I think its not setuped in my firmware. Do you know the Parameter in the firmware, to enable this function.
It ignores it until you home. So instead, check it with M119. It is says triggered only when it touches, then you can try homing Z, and touching it before it bottoms out, with a hand in the power strip.