K40 conversion

Please accept my humble appologies as I’m very new to the cnc game. I bought a Chinese k40 laser cutter in 2014 and never used it. It has a Moshi MS 10105 v4.7 controller on it. I have obtained an M2Nano’s board a LED PAD for it but have no clue how to wire it up. Does anyone have a wiring diagram to convert to the nano board and possibly some pictures. Thanks in advance.

Does your unit have an analog ammeter? See the K40 Intro among other things for why you definitely want one; the digital “ammeters” aren’t ammeters at all.

Also, if you want to start with what you have, see Meerk40t@Tatarize is one of the authors of this open source software that can drive both the M2Nano and Moshi controllers.

There are examples of wiring here, but you might want to post pictures of what you have because different machines were shipped with different wiring.

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Hi Michael
Thanks for the prompt reply and info. I have downloaded meerkat but feel I might have downloaded the wrong thing and cannot get it to open, it just gives me a settings ikon and nothing opens. I’m on Microsoft edge, has anyone else had the same problem?

Please post pictures of: I have obtained an M2Nano’s board a LED PAD




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I’m confused.
Are those pictures of what is in the machine or your replacements? From your description it looks like these are what is currently in the machine?

If they are not then please post pictures of what you want to replace them with.

Hopefully your M2Nano board has the ribbon connector because that takes care of the end stops and one stepper motor. The other connectors( 3 thick wires ) is where 24V, 5V and Gnd are and the smaller connector/wires(4 of them) is the other stepper motor wires.

Are these connectors not available on your M2Nano?

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I have plugged all this into the nano board and I had to add in a wire fit the laser. but the vertical axis does not work.

So everything works but the vertical?

Yes and not sure if I should leave the laser controller as an analog.

I would leave it analog. You can search here and find various opinions.

IMO the led panel does not tell you what the tube is doing it simply controls the IN on the LPS. Its a digital pot.
The analog meter provides tube current which is important so as to keep your tube in the correct operating range.

If you haven’t already check the Y cable for loose connections, pushed pins etc.

Did the Y work with the other board?

You also need a cover on that LPS it outputs lethal voltages…

if anyone has the wiring pinout for the Y axis connector showing the 2 motor coils in pairs then maybe this person could use a DMM and be sure he at least has the motor pairs wired correctly.

You should be able to take a DMM and measure high continuity(low resistance) across 2 pairs of those 4 wires and no continuity between those pairs. When I migrated my K40 M2Nano to Smoothie I had to swap one pair of wires on a connector so maybe that was done to get the Moshi board working and must be undone to get the M2Nano working again.

Over here: K40 M2 Nano Controller and Y motor pinout?

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Perfect Don! So it looks like if that Y motor is wired to be working as it stands there should be low resistance between the Red and Blue wires( coil A ) and low resistance between the White and Yellow wires( coil B ). If that is not the case then you( @Mickmad ) need to find out which wires are paired and move them in the connector.

Thanks for the reply I have already replaced the cover it was only off for the photo. Strangely I have found that if I move the axis by hand and I power the machine up it homes back to the top left and also if I click the centre of the controls on whisper both steppers work. I’m now very confused,