Hi,
I share with you my design of a CNC router. Quite classical, I tried to optimize the ratio working area vs footprint.
Characterictics and Specs:
- main purpose is woodworking, plastic and a bit of aluminium
- dimension 1700x1250
- working area : 1380x920x225
- I left an opened space on the front to be able to fix vertical pieces and machining the side edge (especially for woodworking)
- SFU2005 ballscrew on all axis (1100mm for X, 2x 1500mm for Y and 350mm for Z)
- HGR20 + HG20CA rails & blocks on all axis (1200mm for X, 1700mm for Y and 400mm for Z)
- 4 NEMA34 closed loop (5NM / 6A / 2.2mH) 1 motor per axis except on the Y axis (2 motors)
- 4 HBS86H motoro drivers
- 4 350W 60 VDC power supply (1 per motor)
- 2.2KW spindle (4 ceramic bearing) with VFD (380V both VFD and spindle)
- Double shielded cable for Spindle power
- All others cables (stepper motor, encoder, proximity sensor) are simple shielded
- UC300ETH motion control + UBB1 breaking board and UCCNC software
- Spindle will be controlled by RS485
- 24VDC and 5VDC power supply for motion controller board and proximuty sensor
- 2 inductive proximity sensors per axis (home + limit) + on additionnal on the Y for homeing and self squaring gantry
- 8020 aluminium extrusion based :
- Gantry : 80x160
- Gantry post : 80x80
- Y : 80x120
- the base is made with 3 80x80 and 4 80x40
- the legs are 80x80
- All aluminium plates are 20mm thick
- All the main construction is built on aluminium
- All "accessory" parts and "cosmetic parts" are 3d printed (PETG). There parts are splits to be printed on a "classical" 3d printer (Prusa Mk3s)
For provision : enough space in the control box to add a 5th power supply + driver for a futur rotary axis
Some design choices:
0. All motors are fixed using motor braket with C5 bearing :
1. On the Y axis, the motors and ball screw and below to gain some space on the side
2. I decided to get bigger rails and profiles on the Y axis compared to the ball screw to get approximatively yjr same size than ball screw + motor bracket + motor. By this way i can get longer base for the gantry support
3. I placed the X motor on the back of the gantry to balance it a bit
4. I screwed 2 plates on the sides of the Z plate to enforce it
I've a question : the gantry post are inspired by the AVID CNC (copied ) I also use the 'interface piece' between the posts and the grantry beam, but, to be honest, with understandy the advantage over a simple fasterner
This is quite common, but i will use plywood first hoping having enough rigidity to mill aluminium replacement parts.
I've attached some rendering of the actual design