AC servo motor for CNC mill spindle: Questions and answers

What's worked and what's not about using an AC servo motor (DMM Tech DYN4) on a LinuxCNC CNC retrofitted Precision Matthews PM-25MV milling machine. Many of these questions came from viewers and I hope this summary video will help the next person. I've tried to be very factual but mistakes are likely about the cause for problems that I didn't fully solve. Next video will describe the LinuxCNC DYN4 serial interface.

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Previous video detailing the mounting of the servo motor:    • Make AC Servo Motor Mounts For CNC Mi...  

Various LinuxCNC configurations: https://github.com/kentavv/kvvcreates
DMM DYN4 Python serial module: https://github.com/kentavv/dmm-dyn4
FLIR batch processing Python module: https://github.com/kentavv/flir-batch...
3D model of the mounts, shroud, etc.: https://github.com/kentavv/kvvcreates...

Table of contents
00:00 Introduction
00:32 What are the advantages of the stock BLDC motor?
00:44 Why upgrade the BLDC motor?
01:22 Why not just replace the original drive?
01:40 Why a servo motor? Why not a VFD driven induction motor?
02:20 Why not a servo motor?
03:03 What’s the simplest way to interface the servo motor?
04:24 Is there a more featureful way to interface the servo motor?
06:05 How about torque control mode?
06:28 Why not use the stock v-belt? Aren’t timing belts noisy?
08:03 Why use the motor’s encoder? Isn’t a spindle mounted encoder better?
11:21 Could I have made a more complicated setup?
13:12 Why not use a larger power servo than the original 750W BLDC?
15:02 Why select a servo with a brake? Doesn’t the brake harm performance?
16:09 Is there electrical noise from the servo drive?
18:20 Should the high-voltage electronics be installed into their own enclosure?
19:06 Could the DYN4 serial interface be used?
20:05 Has surface finish improved?
22:59 Are the electronics for a CNC retrofit expensive?
23:39 Does the motor run hot?
24:37 Why has this video taken so long to complete?
25:19 Are the LinuxCNC configuration files available?
25:29 Would I do this all again?
26:10 Thank you

#KvvCreates, #LinuxCNC, #CNC