K40- problems after buying this machine

So hey everyone, few weeks ago I bought this lovely machine, but I didnt expect some kind of problems that happend to me.

So first of all , when I unpacked the box everything looks fine so I started everything and It was going pretty well. The laser mirrors were fine, It was burning, and when I put the ampers higher It was burning more aswell so I was happy… the second thing was installing the driver. After week of searching for problems and what to do I just decided to plug out the flex cable and plug it with the different way inside…(the flex cable was upside down so that was the only thing my driver cant be installed because when I plug the machine to my pc, my pc didnt recognize the machine, lol)
So after one week I successfully installed the driver, turned on the k40 whisperer and then… I press the home position for the laser, and when It goes all the way to top left corner(where it should be) it just didnt stop, like the laser cant find the home position and after like 10-15sec I shut the laser down. I repeat the same thing for 2-3 times and everytime when I press the home position(i moved the laser with my hands to random position) It goes all the way to the top left again but It didnt stop.
So after some hours sitting there I decided to do a little trick. I turn on the machine, I press the home position and after this I unpluged the flex cable, and put it right back, the machine came little bit down and slowly and It was just like- okay im in my home position and ready to burn-LMAO. Then I press the arrows in the k40 whisperer and my laser was working, I dont know how but it works lol…But after all I know that this aint the proper way to use it, but anyway when I repeat this few times the laser was not even working with my “lovely” trick…I was out of ideas with everything, because I was trying to do this with my friend aswell and we were just tirred siting there without any results in hours.

So guys, the question from me is, should I buy new flex cable, or what are my solutions? I take some pictures of my machine and I think that the flex cable is bended and maybe is broken. Btw when I pluged the machine laser tube works, mirrors are good, laser test and switch and ampers are working, water cooling working aswell… I need to put the paint away from the box because of the grounding, but that wasnt the big case of problems. When I plug the machine to the pc everything works, I have the driver and I can move with the axis(sometimes) but as a rookie I need some help from you guys, professionals. I have some photos of the machine aswell and you can see the bend of the flex cable… and btw the picture with white frame on the cable- when I opened the machine for the first that cable was unpluged(it should be only power imo, not sure haha )
sorry for my bad englando guys, but I hope you will understand everything, Im looking forward to some answers and I hope we can turn this machine on :slight_smile:
have a nice day guys.

-As a new member i can only put one picture so i decided to upload the on imgur- lol as a new member I can only put two links so :confused:

here is the cable on my y-axis(im not sure if this is the right way to connect them)

this is the flex cable which was pluged upside down, I just unpluged and plug it other way and the machine start working-lol

this is the cable coming inside my y axis, imo its so bended and probably broken?

this is the cable inside close to the engine of y axis( its close to the cable in the picture above)

and the last one , this is the power supplie and the cables- the white frame was the unpluged red cable( i just plug it back in ) - btw I check the electricity of the power supplie and the board aswell and they both should be good(should)

If I under you correctly the laser head goes to the top left like it is homing but doesn’t stop running once it gets there?

If this is the case I would check the homing end stops. K40s have X and Y optical end stops. You can see one in your first picture.


That black thing this is an optical emitter / receiver unit. There are metal tabs at the end of the stop positions that slide into the space in the middle to block the emitter on one side and register the stop. It looks like those wires may be blocking the endstop. Make sure nothing is blocking the endstops and make sure the metal tabs are sliding into place properly. Let me know if you have any questions.


Good catch Nedman !

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Ey there bro! You were absolutely right, I little bit put down the “metal” from x axis and It has found the way to stop the laser on the point, and the Y axis found its way to the “g spot” aswell, atm I cant tell you more bcaz of the lack of the time I have, but you def help me with this one, when they both go to home position it stops there.

Btw if possible admin- can you let this topic open ? I will write my next steps tomorrow.

best regards


Ey there guys, so when I clean the stuff around the emmiter and turn on the laser, it found its home position. I turned on the pc and run k40 whisperer and everything works out. The problem is fixed. God bless you man, thanks for your time aswell.