I have designed a Z-Table for my K40.
I use a 6mm base plate out of RESOPAL, shoulder bearings F605ZZ (5x14x5mm), stainless M8 threaded rodds (ends turned to 5mm) and a 6mm GT2 belt 1350mm long.
The bed itself will be a replaceable 1.6mm alu mesh fixed to the middle frame.
What do you think about this design?
If you can afford to get lead screws. Threaded won’t last and put more stress on the motor. I’m guessing there are bearing under the pullies too?
Yes, shoulder bearings on both ends. They are sandwiched between the top frame and the bottom plate.
I will try the threaded first, as I have them already. I don’t think they wear too quickly, as the Z-Axis is not used much, and still can replace them when needed.
Keep them lubed and the speed low and you should be fine.
IMO threaded rods are fine for Laser Z table. It’s not like a typical XYZ axis where they are constantly being run and when they do, it’s at low speeds.
I actually 3D printed some some short lead screws. I distorted them a bit by mis-scaling, but they worked better than expected. They definitely would fail quickly if used for a primary axis, but I think they will work fine for my z table. Especially when I print them on a hi-res SLA printer and utilize plastic safe lubricant.
I like the solid bottom plate over the one LO sells. Once lined up I think it will be more stable and less inclined to twist putting load on the motor and belt/pulley system.
I’m thinking of increasing the work size of LO one I have. If I do I think I will be plagiarizing your base design.
@Steve_Clark You are welcome to borrow my design. Just show us the result. 
