Major Updates on my K40

Hi Folks.
I am currently doing a major overhaul on my K40. It may be excessive for some however everything can be moved to a larger bed.

I will be using the UB40OB expansion. I did consider another one however the UB has the advantage of not needing cross members, and the other one that did you could not just drop the new frame in to the K40 Case. Also you are using the case as part of the overall framework.

Upgraded the tube to a 60W 55mm x 1250mm tube. Will be using 100mm acrylic tubing to protect the overhang outside of the K40 case. Have new power supply to handle that. Will also set the tube back a little so I can have a beam splitter and laser pointer installed before first mirror.

Been looking at a simple DIY scissor Lab Jack for the bed height. The main screw can be run cross the base of the K40 case so to give a low profile. This also means that there will be very little supports going across the work area so I can lift out the cutting bed and drop in my rotation mechanism

Processor. Will be using a MKS SBase with a 100mhz processor. GRBL. I have also decided not to keep the MXL belt and gears, but go to the more standard GT2. I already have an CNC machine using the same so working out the new values will be easy.

As for ventilation - I have run a 90mm storm warter pipe around my shop. This has an extractor fan at the end and T-pieces ever meter. Since I have 2 x 3D printer, CNC, and Laser it is just a case of un-stoppering a T piece and plugging the unit to be ventilated in.

Cooling for laser will be a home made chiller using 2 x 15A peltier devices. Each Peltier device has 2 fans, and will be software monitored.

Wish me luck


Sounds like fun! Please post pics and updates when you have time.

Doesn’t make any economical sense, but you will have the unvaluable pleasure to do it !

Wow! Please keep us updated on your conversion process. :smiley:

I think the UK40OB was a @Ariel_Yahni_UniKpty project?

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Although I am looking at his design re the placement of the X stepper. With it on the top there it takes a bit of the X gantry space. Seeing if I can do some rework to claw back those missing millimeters.

Observations on 2 of the more common bed expansions.


The UK40OB has the X gantry running between the two Y rails, where Kosta has his over the Y Rails. This gives the extra space of the Y rail widths, plus his positioning of the Mirror and Stepper over the rail.

One could do the same with the UK40 .

Another problem I see with Kosta’s design is that when you built the frame - it is impossible to put into the laser case. You have to mount it in place. However Areils version mounts to the side of the case eliminating the two cross members.

Perhaps Kosta’s design but using shims to mount the Y rails against, and 2 steppers.

Currently been cutting the case. Added 100mm hole for the excess laser to stick out of. Will be using 100mm acrylic tubing for protection.

Also expanded smoke outlet hole to 120mm for full sized server fan.

Will keep you posted.


Is that the HVPS open frame up under the back panel.
I would advise against using an open frame HVPS, it’s dangerous.
It IS a good idea to get the output as close to the anode as possible however.

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