New Build/PM30-MV Mill/Acorn/DMM DYN4-.75KW X/Y/Z SERVO/1.8KW DMM SERVO SPINDLE

Hello,
I am new to this board, CNC, Machining, ... well everything!
My upcoming build:
- Precision Mattews PM-30MV. Should arrive in a couple of weeks.
- DMM DYN4 & 0.75KW Servo Motor for X,Y. Arrived
- DMM DYN4 & 0.75KW Servo Motor for Z axis with Holding Brake. Arrived
- DMM DYN4 & 1.8KW Servo Motor for Spindle motor. Arrived
- CNC Aluminum brackets and double nut ball screws kit from ArizonaVideo99. Being made.
- DMM power and control cables
- DMM encoder cable for Spindle to Acorn
- Acorn with Pro CNC software
- Dell Touchscreen all-in one.

Spent a LOT of time on youtube. Huge thanks to Youtube's Franko, ArizonaVideo99, CNC4XR7, martyscncgararge. These guys got me gluded to youtube. Right now, I am creating the wiring diagram, the hardest part for me. I am getting there. I have the control cabinet and most of the components to start wiring. Major thanks to DMM's Michael Tien for helping me with the Spindle Servo Motor and cables. Major thanks also to Franko and CNC4XR7 for hooking me on DMM and for the million videos on the PM-727 CNC conversion, most helpfull series of videos for newbies. Thanks also to martyscncgararge for a great variety of CNC videos, especially those on wiring.

Now comes the hard part, getting the PM30 in the basement and actuall doing the conversion. I also have to build a base/stand, learn welding, learn fusion 360 ... I am ecstatic and nervous at the same time.

Side note: I have ordered and received a brand new unopened Delta series M VFD (Single in/3 phase out 220 volts) and its matching braking resistor. Since I am going with DMM 1.8KWServo spindle, I don't need them anymore. Make me an offer if you want to buy them before they go on Ebay.

I also may be interested in selling the Motor that will come-off the PM30MV. It is a 2HP 3000 rpm 220V single phase DC Brushless motor.

__________________________________________________ _____________

First complication to solve: Acorn and DMM z-axis with or without Holding brake

Option 1
DMM 86mm Frame DHT 0.75kW AC Servo Motor With Key

Option 2
DMM 86mm Frame, 0.75kW, medium inertia with +24VDC holding brake

The diffrence between the two is the 24Volt holding brake. I ordered both, but I am returnign one of them,

https://drive.google.com/open?id=12D...HNI6nnnDKtu7ed

(I have to figure out how to insert the picture in the running text, it is not working, please see the link for now)

Two Questions:
1) Do I need a holding brake on the Z-axis Servo?

2) The two DMM Servo motors have the same frame, power and wiring, except for the extra aviation plug (please see red arrow in picture). It is a 3 pin plug. How does this get wired to the Acorn board?

Quote:

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Originally Posted by cnc-geek

Hello,
I am new to this board, CNC, Machining, ... well everything!
My upcoming build:
- Precision Mattews PM-30MV. Should arrive in a couple of weeks.
- DMM DYN4 & 0.75KW Servo Motor for X,Y. Arrived
- DMM DYN4 & 0.75KW Servo Motor for Z axis with Holding Brake. Arrived
- DMM DYN4 & 1.8KW Servo Motor for Spindle motor. Arrived
- CNC Aluminum brackets and double nut ball screws kit from ArizonaVideo99. Being made.
- DMM power and control cables
- DMM encoder cable for Spindle to Acorn
- Acorn with Pro CNC software
- Dell Touchscreen all-in one.

Spent a LOT of time on youtube. Huge thanks to Youtube's Franko, ArizonaVideo99, CNC4XR7, martyscncgararge. These guys got me gluded to youtube. Right now, I am creating the wiring diagram, the hardest part for me. I am getting there. I have the control cabinet and most of the components to start wiring. Major thanks to DMM's Michael Tien for helping me with the Spindle Servo Motor and cables. Major thanks also to Franko and CNC4XR7 for hooking me on DMM and for the million videos on the PM-727 CNC conversion, most helpfull series of videos for newbies. Thanks also to martyscncgararge for a great variety of CNC videos, especially those on wiring.

Now comes the hard part, getting the PM30 in the basement and actuall doing the conversion. I also have to build a base/stand, learn welding, learn fusion 360 ... I am ecstatic and nervous at the same time.

Side note: I have ordered and received a brand new unopened Delta series M VFD (Single in/3 phase out 220 volts) and its matching braking resistor. Since I am going with DMM 1.8KWServo spindle, I don't need them anymore. Make me an offer if you want to buy them before they go on Ebay.

I also may be interested in selling the Motor that will come-off the PM30MV. It is a 2HP 3000 rpm 220V single phase DC Brushless motor.

__________________________________________________ _____________

First complication to solve: Acorn and DMM z-axis with or without Holding brake

Option 1
DMM 86mm Frame DHT 0.75kW AC Servo Motor With Key

Option 2
DMM 86mm Frame, 0.75kW, medium inertia with +24VDC holding brake

The diffrence between the two is the 24Volt holding brake. I ordered both, but I am returnign one of them,

https://drive.google.com/open?id=12D...HNI6nnnDKtu7ed

(I have to figure out how to insert the picture in the running text, it is not working, please see the link for now)

Two Questions:
1) Do I need a holding brake on the Z-axis Servo?

2) The two DMM Servo motors have the same frame, power and wiring, except for the extra aviation plug (please see red arrow in picture). It is a 3 pin plug. How does this get wired to the Acorn board?

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The Brake circuit normally is a separate circuit, that gets turned on when the power is turned on ( to Power the Servo Motor ) and off when the power is turned off to the servo motor, it does not have to be going through the Breakout Board, the Brake must be activated while and when the motor is power up, the Brake can not be locked when power is on the Servo Motor

Do you need it that depends if your Z axes and Head moves down by it's self once the power has been turned off, if this happens then it is good to have some kind of brake on the Z axes

I wouldn't opt for brake myself, another thing that could go wrong.
I don't see the need for it on the Z unless it drops on it's own. In which case just put a stronger gas strut on there.

Hi, correct me if I am wrong but I think I have read somewhere that brakes are also helpful to improve acceleration/deceleration. If I can understand it for the second, that's brakes purpose after all. I hardly grasp how it can help acceleration...

Is it because torque rises before the brake is disabled? So there is a delay?

Or is it in the cases of change of direction where, improving the deceleration phase, the branles shorten the change both in time and travel?

May be the second one because now I think I've seen this in the context of 3D carving, to improve/accelerate Z axis mouvements.

Envoyé de mon ONEPLUS A5010 en utilisant Tapatalk

Quote:

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Originally Posted by silopolis

Hi, correct me if I am wrong but I think I have read somewhere that brakes are also helpful to improve acceleration/deceleration. If I can understand it for the second, that's brakes purpose after all. I hardly grasp how it can help acceleration...

Is it because torque rises before the brake is disabled? So there is a delay?

Or is it in the cases of change of direction where, improving the deceleration phase, the branles shorten the change both in time and travel?

May be the second one because now I think I've seen this in the context of 3D carving, to improve/accelerate Z axis mouvements.

Envoyé de mon ONEPLUS A5010 en utilisant Tapatalk

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You are mistaken, and if you read this, you have been fooled by someone that has no clue of what they are talking about, Brakes are of no use what's so ever for servo operation, when the main power is turn on the Brake has to be disengaged, when the power is turned off the Brake is locked, A Brake has no other function than holding an axes when the power is turned off

Thank you for clarifying [emoji106]

Envoyé de mon ONEPLUS A5010 en utilisant Tapatalk

Is there any news on the build? How are 0.75kW servos work on that machine?

Quote:

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Originally Posted by JKSniper

Is there any news on the build? How are 0.75kW servos work on that machine?

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I ordered the PM-30MV in early June, with delivery ETA of mid July. I still have not received it. I have been told by PM that I should expect delivery early November. The CNC kit is also not ready yet. A lot of waiting! Ounce things get going, it will be super busy. Until then, I am rebuilding a vintage southbend 9 lathe, almost done with it too.

Sent from my SM-N910V using Tapatalk

Why did you decide for those drives? I've bought BF30 from Bernardo, which seems to be very similar to PM30 and it lies in parts right now. I'm stuck on deciding on drive for it. Check my thread if you have some recommendation for me - please! :)
https://www.cnczone.com/forums/bench...67842-cnc.html

Quote:

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Originally Posted by JKSniper

Why did you decide for those drives? I've bought BF30 from Bernardo, which seems to be very similar to PM30 and it lies in parts right now. I'm stuck on deciding on drive for it. Check my thread if you have some recommendation for me - please! :)
https://www.cnczone.com/forums/bench...67842-cnc.html

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I am new to this. So take what I say accordingly. Servos vs. Stepper Motors is a no contest in favor of Servos. When you can get decent servos at similar pricing to steppers, then to me, it was not even much of a decision. DMM tech servos and drives made a lot of sense to me. Plus I found many references and video on how to's. So I went with them. Not very scientific, plus it is hobby for me and I was willing to spend a little extra.

Sent from my SM-N910V using Tapatalk

Someone (more experienced) just suggested me to use 1:3 belt drive (HTD or GT3) on those servos, because their nominal speed is 3000RPM, which is on 5mm ballscrews = 15m/min, which would destroy the machine and the castings etc. 1:3 ratio would give max speed of 5000mm/min, which is around 200IPM, which is kind of maximum what you want to run on such machines anyway... Also torque is much higher, precision gets higher, accelerations etc. etc. May be good option I guess.

Quote:

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Originally Posted by JKSniper

Someone (more experienced) just suggested me to use 1:3 belt drive (HTD or GT3) on those servos, because their nominal speed is 3000RPM, which is on 5mm ballscrews = 15m/min, which would destroy the machine and the castings etc. 1:3 ratio would give max speed of 5000mm/min, which is around 200IPM, which is kind of maximum what you want to run on such machines anyway... Also torque is much higher, precision gets higher, accelerations etc. etc. May be good option I guess.

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That does not make any sense to me. The Acorn CNC board will control the rpm of the servos. Their max rpm is not relevant. When I get a chance I will post link to the two youtube vids that convinced me to go with my setup. It is a very similar set up to the one I chose.



Sent from my SM-N910V using Tapatalk

Sure you can throttle down servos, but if you use servos only in 0-10% of their RPM range, they can be hard to tune and you're wasting basically all of their potential...

Quote:

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Originally Posted by JKSniper

Sure you can throttle down servos, but if you use servos only in 0-10% of their RPM range, they can be hard to tune and you're wasting basically all of their potential...

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No tuning problem with the Dmm servo's, Ac servos don't care what speed they are run at they have the same performance at any speed

It does not matter how he wants to run the servo's on a machine like this with these 750w servos he can use them 1:1 on the X axes and Y axes the Z axes will need a reduction depending on the weight of the head

There is basically no tuning with the Dmm servo system, they have adaptive tuning control and are constantly self adjusting to the load they are experiencing

AC servos' torque vs. speed graphs are about linear so he is not loosing torque and it is also not harder to tune them for low RPM.
However using a geardown increases the torque on the secondary gear which can increase dynamics of the control loop.

How do those servos compare to 3 phase steppers?
Leadshine Technology Co., Ltd.

When directly driven, it seems they could work great in full range of expected speeds... Is there any other consideration when choosing the optimal drive?

Quote:

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Originally Posted by JKSniper

How do those servos compare to 3 phase steppers?
Leadshine Technology Co., Ltd.

When directly driven, it seems they could work great in full range of expected speeds... Is there any other consideration when choosing the optimal drive?

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There is no comparison between the steppers and servo's, Leadshine do make some good drives for steppers, it all come's down to what do you want out of your machine

Normally you want to have with any modern AC servo the matching servo drive, most don't play nice if you try to mix and match

The problem is that I'm deciding between:

Option 1:
-2x DMM DYN4 driver & 0.75KW Servo Motor for X,Y (Direct drive)
-1x DMM DYN4 driver & 0.75KW Servo Motor for Z axis with Holding Brake (1:2 or 1:3 with GT3 or HTD belt)
Servo link: https://dmm-store-shopify.myshopify....ac-servo-motor
Driver link: https://dmm-store-shopify.myshopify....ac-servo-drive

Option 2:
-3x ES-MH33480 8Nm 3phase highvoltage closed-loop stepper (direct drive on X,Y,Z)
-3x ES-DH2306 230VAC closed loop driver for this motor
Stepper link: Leadshine Technology Co., Ltd.
Driver link: Leadshine Technology Co., Ltd.

Both options are basically the same price. On this machine real max. rapids are around 2000mm/min, or let say 3m/min just to be sure we can reach them. With 5mm ballscrews that's 600RPM or 10RPS.
Servo has 2.4Nm flat torque @ 0-600RPM / 3 Phase closed-loop stepper has 8.5Nm@0 RPM- > 6.2Nm@600RPM.

Reading Leadshine note on their "easy servos" = closed loop 3phase high-voltage steppers:
When driven by a Leadshine 3 phase ES-DH easy servo drive to take direct 120/220/230 input voltage, the position loop between the motor and drive is fully closed. Therefore, loss of steps which limits adoption of stepper systems is totally eliminated. Because there is no torque resolution needed like in open loop stepper systems, you can much better high-speed performance than open loop stepper systems by increasing up to 30%. Such systems are also ideal to replace brushless servo systems to offer huge starting and low speed torque.
Based on latest DSP technology and adopting Leadshine's advanced control algorithm, ES-DH2306 easy servo drive applies servo control on easy servo motors. When adopted with an easy servo motor, it combines features of both open loop steppers & brushless servo systems, and offers many unique advances features for excellent motion control system performance.
Same as servo drives in traditional brushless servo systems, an ES-DH2306 easy servo drive takes encoder feedback from a driven ES-MH series easy servo motor to close the position loop and eliminate the possibility of lose of movement synchronization. Therefore, loss of steps which limits adoption of stepper systems is totally eliminated in ES-DH2306 driven easy servo systems. Compared with constant output current in open loop stepper drive, output current from an ES-DH2306 servo drive to the driven motor is load based. When torque requirement is low, the output current is automatically lowered to the level of "just enough". But when the torque requirement is high, an ES-DH2306 easy servo drive can boost the output current quickly, up to 6.0A. This can significantly improve control system response time, offer excellent acceleration performance, and reduce motor heating by as much as 50% over open-loop stepper systems. Also, there is no torque reservation needed for an ES-DH2306 driven easy servo system. In an ES-DH2306 driven easy servo system, it always allows 100% torque implementation available from the driven easy servo motor and thus improves system high speed performance by as much as 30% over comparable open loop stepper systems. In addition, smoothness and quietness are also significantly improved in ES-DH2306 driven easy servo systems over steppers.
Compared with traditional brushless servo systems, cost for ES-DH2306 driven easy servo systems is significantly lower. Starting and low-speed huge output torque from an EM-DH2306 driven easy servo motor is way higher than torque from simliar size brushless servo motors. Such systems also outperform comparable traditional brushless servo systems for high standstill stiffness, no hunting (shaking), no overshooting, almost zero settling time, and plug-and-play setup with no tuning for most applications. In addition, plug-and-play setup for almost all applications makes ES-DH2306 driven easy servo system much simple to set up, over hard-to-configure brushless servo systems which usual involve configurations of tens of parameters.

Based on this information, which drive would you go with?

Thank you so much for your input! I'm literally a click away from one of this offers, but I don't know which one to take as optimal or inferior.

Best regards,
Jure

Quote:

---

Originally Posted by JKSniper

The problem is that I'm deciding between:

Option 1:
-2x DMM DYN4 driver & 0.75KW Servo Motor for X,Y (Direct drive)
-1x DMM DYN4 driver & 0.75KW Servo Motor for Z axis with Holding Brake (1:2 or 1:3 with GT3 or HTD belt)
Servo link: https://dmm-store-shopify.myshopify....ac-servo-motor
Driver link: https://dmm-store-shopify.myshopify....ac-servo-drive

Option 2:
-3x ES-MH33480 8Nm 3phase highvoltage closed-loop stepper (direct drive on X,Y,Z)
-3x ES-DH2306 230VAC closed loop driver for this motor
Stepper link: Leadshine Technology Co., Ltd.
Driver link: Leadshine Technology Co., Ltd.

Both options are basically the same price. On this machine real max. rapids are around 2000mm/min, or let say 3m/min just to be sure we can reach them. With 5mm ballscrews that's 600RPM or 10RPS.
Servo has 2.4Nm flat torque @ 0-600RPM / 3 Phase closed-loop stepper has 8.5Nm@0 RPM- > 6.2Nm@600RPM.

Reading Leadshine note on their "easy servos" = closed loop 3phase high-voltage steppers:
When driven by a Leadshine 3 phase ES-DH easy servo drive to take direct 120/220/230 input voltage, the position loop between the motor and drive is fully closed. Therefore, loss of steps which limits adoption of stepper systems is totally eliminated. Because there is no torque resolution needed like in open loop stepper systems, you can much better high-speed performance than open loop stepper systems by increasing up to 30%. Such systems are also ideal to replace brushless servo systems to offer huge starting and low speed torque.
Based on latest DSP technology and adopting Leadshine's advanced control algorithm, ES-DH2306 easy servo drive applies servo control on easy servo motors. When adopted with an easy servo motor, it combines features of both open loop steppers & brushless servo systems, and offers many unique advances features for excellent motion control system performance.
Same as servo drives in traditional brushless servo systems, an ES-DH2306 easy servo drive takes encoder feedback from a driven ES-MH series easy servo motor to close the position loop and eliminate the possibility of lose of movement synchronization. Therefore, loss of steps which limits adoption of stepper systems is totally eliminated in ES-DH2306 driven easy servo systems. Compared with constant output current in open loop stepper drive, output current from an ES-DH2306 servo drive to the driven motor is load based. When torque requirement is low, the output current is automatically lowered to the level of "just enough". But when the torque requirement is high, an ES-DH2306 easy servo drive can boost the output current quickly, up to 6.0A. This can significantly improve control system response time, offer excellent acceleration performance, and reduce motor heating by as much as 50% over open-loop stepper systems. Also, there is no torque reservation needed for an ES-DH2306 driven easy servo system. In an ES-DH2306 driven easy servo system, it always allows 100% torque implementation available from the driven easy servo motor and thus improves system high speed performance by as much as 30% over comparable open loop stepper systems. In addition, smoothness and quietness are also significantly improved in ES-DH2306 driven easy servo systems over steppers.
Compared with traditional brushless servo systems, cost for ES-DH2306 driven easy servo systems is significantly lower. Starting and low-speed huge output torque from an EM-DH2306 driven easy servo motor is way higher than torque from simliar size brushless servo motors. Such systems also outperform comparable traditional brushless servo systems for high standstill stiffness, no hunting (shaking), no overshooting, almost zero settling time, and plug-and-play setup with no tuning for most applications. In addition, plug-and-play setup for almost all applications makes ES-DH2306 driven easy servo system much simple to set up, over hard-to-configure brushless servo systems which usual involve configurations of tens of parameters.

Based on this information, which drive would you go with?

Thank you so much for your input! I'm literally a click away from one of this offers, but I don't know which one to take as optimal or inferior.

Best regards,
Jure

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It's what you want to go with AC servos will always be much better over all that any stepper system no matter what they say DMM only have ( 3 ) Parameters to set and ( 2 ) other selections so a total of ( 5 ) settings to make, and have auto tuning, so basically nothing to set if you don't want to play with the Servo Drive, Encoder 16 Bit 65,536 ppr this is the part you lack with steppers, which is needed for any CNC machine if you are serious about any type of machining wood working does not matter so much, the Encoder ppr will determine how smooth the machine runs, so the bigger this number is the smoother your machine will run

For the servo you would have to be looking at the Peak Torque not the Rated Torque, to do any comparison, when you command a move the servo will ramp up to the max Rated Torque at any RPM even from zero RPM the rated Torque is what the holding torque will always be

How do I say this without sounding insulting. People who have no practical experience should not be giving advice about AC servo motors. They are very different from even closed loop steppers.

On paper, the steppers seem to be just as good until you realize that the thousands of steps are frequently very random in the amount they move. Micro-steps should be called micro-guesses. Most of the drivers are toys, some even using old centronics d shell connectors and other DIY type parts to keep the price down. Most of the designs I've seen were just home type circuits with little noise, current or any sort of interference or safety built in. While they have their applications, steppers are just a low cost option and you get what you pay for.

A proper AC servo and amplifier is designed for 20+ years of continuous use, can control torque, spin at 3000 rpm and stop within a fraction of a degree. They have proper logic, faults, and good inertial modeling. The hybrid stepper idea is not a new one, yet nobody uses them in industry. My Panasonic drives can happily hold in place or turn at 1 RPM if they need to. Adding a reduction timing belt to it is going to add complexity and inertial slop with no added benefit. A gear is going to add backlash. Nobody does this, and while industrial mills can go quicker than our home toys, they still don't use near 100% of the motors RPM capacity.