Hi guys,
I'm a CNC newbie and would like some quick advice on choosing the right motors for my WMD30V milling machine and WM290F-V lathe.
This is the driver I've got: Wholesale Product Snapshot Product name is 3 Axis CNC Kit Router TB6600 Stepper Motor Controller Box Set 5A with LCD Digital Display Drop Shipping
This is the PSU I'm considering: High Quality Power Supply 36V 320W AC to DC Power Supply AC DC Converter S 320 36-in Switching Power Supply from Electrical Equipment & Supplies on Aliexpress.com | Alibaba Group
And this is the motor I'm considering: NEMA23 425 Oz in CNC Single shaft stepper motor stepping motor/3.0A-in Stepper Motor from Industry & Business on Aliexpress.com | Alibaba Group
The seller recommends me to go with the 23HS2430 model because of motor heat issues with the 23HS2410.
The reason I was looking at the 23HS2410 model was because of lower inductance and lower steady state DC voltage over the motor, which means that the 42V supply my controller will safely handle is comparatively higher for the 23HS2410 motor. The 23HS2430 motor would require 27% higher supply voltage to give the same performance.
Here are my admiddetly very basic calculations:
Motor I R L Ƭ=L/R U=I*R P=U*I 23HS2410 4,2 0,9 0,0038 0,0042 3,78 15,9 23HS2430 3,0 1,6 0,0068 0,0043 4,80 14,4
I wanted adequate high speed performance (man is that a poor spec or what?) and thought that while the L/R time constants are nearly equal, the lower voltage would be an advantage to my controller that has limited supply voltage range. I need a bit of safety margin so I though I could drive it with a 36V PSU with the adjust pot turned to max giving about 42V DC.
There should be a 27% speed increase with the 23HS2410 motor, which is not that much, at the expence of 1,5W more being burned off in the windings causing 10% more heat and an extra 1,2A load on the drivers nearly eliminating the derating from the maximum 4,5A spec.
Is that worth it to gain a little extra speed, or should I listen to the seller and go with the 23HS2430?
Right now I'm more inclined to go with the sellers recommendation because of the reduced load on my driver, but I would like to hear your thoughts on this.
And if I've made a mistake in my reasoning please feel free to point out my mistakes. This is after all my first CNC conversion, and I'm here to learn.
Best regards
Soren