After building a couple of 3d printers, and building and struggling to do anything with an MPCNC, iv decided its time to make a proper cnc router.

Design criteria are,
Desktop machine with foot print no bigger than 1050 by 850 to fit on my existing bench.
Make use of the 4 750mm SBR16 rails, and 2 300mm SBR16 rails I have buried somewhere in the workshop.
Capable of cutting the end of sheet timber to make box joints.
Reduce costs where possible without affecting performance.

After alot of reading, and a few design iteration, this is what i have come up with.
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Z axis,

Both plates are 15mm thick aluminium ecocast. 140mm travel, 1605 ball screw. mass aprox 7kg.
3.1nm motor connected by belt drive. (The motor plate inst shown in the image)
Tramming will be done by a eccentric bush and shims between the X axis plate.
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X axis and Gantry

Gantry is made from welded steel box section. Bottom piece is 100x60x3, top 60x60x3, short connecting pieces are 60x40x3.
The two end end connecting pieces will be bolted in place so the ball screw mounts can be easily adjusted if needed. Also if at some point in the future i decide to swap the SBR16 rails for hiwin stile rails I will be able to easily move the ball screw back into the gantry to suit. Rail surface will be epoxy leveled.
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X axis plate is 10mm thick ecocast. I dont think there is any need for anything thicker here as it will be bolted to the 15mm thick Z axis plate.
Gantry ends are 10mm thick aluminium flat bar or plate. The Y axis bearing are fixed almost directly to the underside of the gantry, so the gantry ends will only carry load in the Y direction, so no need for anything too thick.The gantry ends will be fixed to both the top and bottom steel gantry tubes. Two small pieces of 20mm thick aluminium ecocast are bolted directly to the underside of the gantry, these will be bolted to the Y axis plates. Shims can be placed between these two plates to level the gantry if needed.
Connecting the bottom of the gantry ends will be a piece of 60x20 extrusion. The Y axis ballnuts will be attached to this.
X axis drive will be 1610 ball screws, with 3.1nm motor connected with belt drive.
I plan to connect the motor to the gantry end plate with some long spacers. This hasnt been included in the model yet.
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Total length 900mm, rail length 750, travel 600mm.
Mass approx 25-30Kg

Base frame and Y axis

Base frame is made from wedled 60x60x3 and 60x40x3 steel. Rail surface will be leveled with epoxy. 1610 ball screws are under the bed to reduce the machine foot print. Id like to drive this with just 1 nema 23 3.2nm motor. Is this possible with a gantry approaching 40kg?
The machine will sit on 4 adjustable feet which are not in CAD yet.
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To give you an idea of the space constrains, this is a plan view of the current design with the workbench parameter shown.
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Total machine weight is around 70kg.
Cutting area will be around 600x600.
Gantry clearance 140mm from the steel base frame. 120mm ish after adding a bed.

Id love to get some feed back on the design before I start ordering parts or cutting metal.
Also im struggling with where to buy the electronics and what to buy, any advice would be really helpful.
im also yet to choose a spindle. Id love a 2.2kw water coolded one, but they are bloody expensive and if possible id rather not have to bother with water cooling. Any suggestions?