Newbie first build of hobby wood CNC mill, have been reading a lot here and other site, these are the decision I made. I also wanted parts that could be used if I upgraded/bigger my build. See picture of the design that I build. The useable bed is 19” x 15” and all is driven by 1/2” 13 threads per inch and I am using a full size router.


Attachment 227170


Attachment 227172


I bought this stepper motor
KL23H2100-35-4B 381 oz In. Hybrid Motor 1.8° /200 Steps Per Rev. 3.5 Amps Current Per Phase, Inductance 2.8 mH, 0.73 ohms.
4-wire 2.55 rated volts Bi-polar, NEMA 23 Frame

NEMA23 381oz/in 3.5A Dual Shaft Stepper Motor KL23H2100-35-4B | Automation Technology Inc

Reading found the following rules of thumb need 300 to 400 oz-in and the lower the Inductance the lower the drive voltage could be. Another rule was the needed power supply voltage, should be 20 time the coil rating. So went looking for a max power supply voltage of ( 20 x 2.55 ) 51 volts.

The driver that I was going to use was a 6064: 4AMP Stepper Motor Driver Kit. Drives 4.5 Amps (peak) and 4 Amp sustained at 50 volts. This is a new driver that is now being offer. Also used their 4Axis5: BOB/Pulse/Power. Note if you are going to use the 5 v reg on the BOB board it has a 35 V max input.

THB6064 MassMind Stepper Motor Driver Kit

Because of the above, I was looking for a power supply that could be adjusted from 30 to 50 volts.

I ended up with this from ebay 32V-40V Adjust DC 9.7A 350W Regulated Switching Power Supply

32V 40V Adjust DC 9 7A 350W Regulated Switching Power Supply Quality from USA | eBay

Had an old XP desk top computer and went with Mach3. Seem like everybody uses Mach3.

Software & Downloads - Newfangled Solutions

I am still at a lost as to what Cam software to get as I have an old copy of Solidworks that I would like to use. Here is a site that has a good list of what is being used by others.

The Results are in on the CAM Package Survey - CNCCookbook CNC Blog CNCCookbook CNC Blog

Summary:

The power supply had the pot gliped with a strong paint and I damage the pot trying to adjust. So had to take apart the supply and install a new pot ( voided warranty) . I have it set at 33volts and seem to be working well. ( 2 volts under the 35 V max of the 5v reg.)

The 3 stepper motors looked new but one had been drop and cut the wires coming out of the housing. There is a sharp edge that will do this easily if not handle carefully. I was able to repair. The motor run warm but not hot. The current is set at 3.5 amp at the driver. The chips that drive the motors are running cool. On the bench I was able to drive the stepper at 950 RPM if I was doing the calculation right.

The driver are a kit that you have to put together, I got the kit that had 3 driver and BOB board with cables and reg and did the assy. All the part were there and the instruction are well done. The PC boards are good and will take a lot of heat without the pads lifting. Part location is by part designator or value, would have liked to see all part designator. The driver and stepper motor play well together. The biggest problem I had was getting the Mach3 set up to drive them ( I am not good at reading instruction). The driver board needs 3 signals: step, direction, and enable signal. Having got the BOB board/cables was a great aid, it was also a kit, again all parts were there but you need a heat sink for the 5 v reg. Also one part, the leads were to big to fit the mounting holes. Also since I was using the motor supply voltage to the 5 Vreg I need to place 280 ohms 2 watt in the supply line to dissipate some of the heat. The 3 driver board were pulling .08 amp total.

All is working great and the system tops out at at 75 ipm at 10 micro steps but have been running at 50 ipm. I was hoping for .01 accuracy and think I am getting better then that so all is good.

All vendors deliver very quickly and I was sent notice when they had ship, I did not contact any vendor so do not know how they respond e-mails.

I am writing this to give other an idea what has work for me, as I pulled a lot of information from a lot of place and still was not sure if I was making the right decision. I hope the above information helps someone who is looking to build their first CNC.