Question: Reusing MPCMC as a 3d Printer

This is the question out of curiosity, my MPCNC is still printing. I understand that there is a separate project for mp3dp but if possible I’d love to just change the tool on MPCNC and use it as 3d printer on the fly whenever i want.

  1. I have seen some people use their MPCMC as a 3d printer. What does it take to do that? I understand that my z axis is pretty small (only 3.5 inches) so i am limited to that height. I think, I need an open slot for the extruder motor on the board. And an actual extruder itself. Is that correct? How would I print the mount for the extruder to fit on the MPCNC?
  2. Is it possible to just change the z height for the rails without changing the leg assembly size?

My current MPCMC has a small build area for sturdiness, here are the details:

I have heard of at least one person switching z rails to gain hight. If you need more “leg” hight you can use a drop table. You will also want a heated bed if you plan on printing.

@forcerouge do you have any tips for him? I know you used the mpcnc as a printer for a while.

The MPCNC as a 3D printer works well. It won’t win any speed records, but it’s perfectly capable. I did this last week.

The green one was the first test that I tried at 60mm/sec ended up stalling at about 75% due to some board malfunction. The white one was printed at 40mm/sec at .2mm layer height.

As for the height, you would have to cut longer legs to accommodate the longer Z axis. My guess is that the increased Z and leg height wouldn’t adversely effect the operation as there wouldn’t be any lateral strain on the Z since there isn’t any real contact like you would have with a bit plowing through stock. But I’m no kinda engineer.:wink:


There are too many things to say about how to convert the MPCNC to 3D printing, so maybe you can check my old build’s thread first:

No need to read everything, but you should find the answers to most of your questions there
Basically you’ll have to add:
-an extruding system (motor, hotend, temp sensor, cooling fan for the cold side, etc).
-endstops, for homing on all axes
-fans for cooling the part
-a probe system to measure bed’s flatness. This is not entirely mandatory but it helps so much in getting a decent first layer that you really should consider it from the beginning
-a bed heating system. Not mandatory if you plan on printing small parts with PLA.

You’ll have to adapt the firmware a little bit but we’ll be there to help you.
One thing is that you can’t use the autosquare function in CNC mode, because you’ll need 4 axis for the printer.

Good luck and don’t hesitate to ask if you have any problem :slight_smile:

You could use the autosquare with 3d printing, you just have to have at least 6 stepper drivers. 2 for x 2 for y 1 for z and 1 for extruder. :slight_smile: unless I’m missing somthing?

Yeah in theory this might be doable, but I don’t think our friend here is ready to go to this step just yet :wink:

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