548,605 active members*
2,621 visitors online*
Register for free
Login
Page 1 of 7 123
Results 1 to 20 of 128
  1. #1
    Member
    Join Date
    Dec 2018
    Posts
    49

    Controller Advice Needed

    Hello,
    I am trying to decide which way to go with the controllers/motors for my build. I really like the idea of the Blackbox and the xPRO V5 for their simplicity but I am not sure if I would be getting the best bang for my buck. From what I have read they are great controllers but due to the limited power (24v) I would be limiting my motor selection/performance.

    I originally planned to purchase the stepperonline nema 23s (425oz) but have read that it is better to go with lower torque ones with either of these controllers. I read this snippit from an article comparing the two control systems.
    So what do the values imply in terms of the stepper motors that can be run by these controllers?

    The peak current of 6A for the driver implies that the xPRO v5 can run stepper motors with up to a 6A rating (theoretically).

    But since you need to extract the full output (torque at high speeds) of the stepper motor, ideally the peak current of the driver should be 1.4 times that of the stepper motor.

    Using this thumb rule, you can use a 4.2A stepper motor (NEMA 23 and some NEMA 34 stepper motors) with the xPRO v5.

    And you can use up to a 2.8A stepper motor with the BlackBox controller such as this highly popular 269 oz.in NEMA 23 stepper motor.

    However, even with the xPRO v5, the power that you can supply is limited to 24 volts.

    High torque NEMA 23 motors such as this 425 oz.in NEMA 23 motor requires 36V of power to deliver the high torque you need at high RPMs.

    Powering it at 24V is fine but it will limit the torque you get.

    For knowing how much torque you can extract out of a stepper motor at each voltage and RPM, you need to refer to the torque vs RPM chart of the motor.

    To know if you'll get higher torque out of your stepper motor with the xPRO v5 compared to BlackBox, you need to see how much torque the high torque stepper motor can generate at 24V, which is the maximum recommended power for the xPRO v5.
    I have tried to find torque specs for the different nema 23s at 24v but have been unable to. Was hoping you guys can help shed some light on this for me (and others in my same situation).

    The above snippit mentions that you can use up to 4.2a motors on the xPRO and 2.8a on the Blackbox. Does this mean that although we would be limiting the performance because of the lower volts, the xPRO would provide higher torque/performance than the BB using the same motors? It is my understanding that...
    • Speed is proportional to voltage
    • Torque is proportional to current (amps)
    • Power is the product of speed x torque

    Please correct me if I am completely off here. Still trying to learn all this.

    I am having a hard time really understanding what all this means.

    I would be open to buying individual pieces instead of one these if it is not too technical or difficult to get up and running and if it were a much better value to performance ratio.

    Would love to get some advice and personal experience with any/either/all of these options.

    BTW, my setup is a 48"x48" with plans for wood, plastics and aluminum.

    Thanks for any advice!

  2. #2
    Registered
    Join Date
    Nov 2013
    Posts
    1478

    Re: Controller Advice Needed

    HI,
    don't waste your time trying to run steppers at 24V. They will have their rated torque but the torque will fall off a cliff at any speed.

    with stepper:

    Current=Torque (and heat!)
    Voltage=Speed

    You want stepper drivers that can handle 80VDC....then they will move for you.

    You need low inductance steppers:
    With 23/24 size stepper look for 1mH-2mH inductance, 1mH preferred and reject anything over 2mH
    With 34 size steppers look for 2mH-4mH inductance, 2mH preferred and reject anything over 4mH

    Craig

  3. #3
    Registered
    Join Date
    Jan 2018
    Posts
    1041

    Re: Controller Advice Needed

    Seriously?.
    Those tiny things are designed for a light engraver or 3D printer type machine.
    Have a look at you bog standard 6x4 (6040) Chinese aand see what they have fitted.
    You are talking about something similar size.

    Talk to this guy who builds routers for a living:
    View Profile: JAZZCNC - MYCNCUK


    • Speed is proportional to voltage
    • Torque is proportional to current (amps)
    • Power is the product of speed x torque


    These above are correct.. If you want both speed and torque (as budget as poss) you want:

    These: https://www.aliexpress.com/item/1005003297280563.html?spm=a2g0o.productlist.0.0.4e 1b28eaKWREIi&algo_pvid=e090419e-ee20-42be-a9b5-94895ee68812&algo_exp_id=e090419e-ee20-42be-a9b5-94895ee68812-52&pdp_ext_f=%7B%22sku_id%22%3A%2212000025077653105%2 2%7D

    These (or as close as poss): https://www.aliexpress.com/item/3286...51a318c1O1cImV
    *****Wired in PARALLEL****** This gives only 1.8mh inductance at 5.66A which the 860 drivers will do easy. They'll fly!
    The 425oz ones are 4.2A but 3.8mmh inductance so will be slower than the above and prone to resonance.

    Run it all off one of these: https://www.aliexpress.com/item/1005...45015322%22%7D
    This will be comfortable with running 4 of these 5.6A motors above. (60v 1000w).

    You can control it with the usual board in the 6040: https://www.aliexpress.com/item/1005...99820315%22%7D

    Or offline: https://www.aliexpress.com/item/4000...01269453%22%7D
    Or arduino with GRBL.
    Or Linux based board.
    Or something like a uc400eth (best in my view).

    It all seems extreme but
    1 You want it to be reasonably good and be strong enough to cut aluminium.
    2. Give it a month or two and you'll move all this kit onto something bigger, so will need it!.
    3 Simple, pre-build, ready to go equipment, in the diy hobby world normally means..... Absolute CRAP!!!!

  4. #4
    Registered
    Join Date
    Nov 2013
    Posts
    1478

    Re: Controller Advice Needed

    Hi,
    all steppers lose torque the faster they go, that's just the physics of how they work.

    Inductance (of the windings) is a good measure of how bad the torque degradation will be, the lower the inductance the better.

    Most newcomers do not understand inductance and focus solely on torque. A 800 oz.in stepper has got to be better than a 400 oz.in stepper right?
    If the 800 oz.in stepper has 8mH inductance its torque will drop off rapidly, probably only have 5% at 1000 rpm, that is only 40 oz.in. The 400 oz.in stepper
    on the other hand with an inductance of 2mH may have 30% of its torque at 1000 rpm, that is 120 oz.in. Thus you can see that the low inductance stepper outperforms
    the higher torque (with comensurately high inductance) at speed, so the machine would stall with the high torque stepper but carry on machining with the lower
    torque motor. Go figure!!!

    Stepper manufacturers know very well that newcomers focus on torque alone so they make steppers that have really great torque but shocking inductance....just to get the
    sale. Smart buyers know that a balance must be struck between inductance and torque.

    The classic method to minimise torque degradation with speed is to use high voltage drivers with a high voltage supply. I would strongly recommend both, if you buy well you'll have
    them for years......if you skimp you'll have to throw them out in a month.

    Craig

  5. #5
    Registered
    Join Date
    Jan 2018
    Posts
    1041

    Re: Controller Advice Needed

    Quote Originally Posted by joeavaerage View Post
    HI,
    don't waste your time trying to run steppers at 24V. They will have their rated torque but the torque will fall off a cliff at any speed.
    with stepper:
    Current=Torque (and heat!)
    Voltage=Speed
    You want stepper drivers that can handle 80VDC....then they will move for you.
    You need low inductance steppers:
    With 23/24 size stepper look for 1mH-2mH inductance, 1mH preferred and reject anything over 2mH
    With 34 size steppers look for 2mH-4mH inductance, 2mH preferred and reject anything over 4mH
    Craig
    I've just given some examples. I think I'm with you on most of this.
    In fact. I've just tested my new DM860T (110vdc) driver on 80vdc supply for running my 1080oz/in nema34 stepper. It's made it surprisingly so smooth and quiet with only a 20v jump.


    These look pretty good 24's: https://www.omc-stepperonline.com/ne...m-4-wires.html

    I have these type but they still fly on 60v: https://www.omc-stepperonline.com/ne...s39-4204d.html

  6. #6
    Registered
    Join Date
    Jan 2018
    Posts
    1041

    Re: Controller Advice Needed

    Quote Originally Posted by dazp1976 View Post
    You can control it with the usual board in the 6040: https://www.aliexpress.com/item/1005...99820315%22%7D

    Or offline: https://www.aliexpress.com/item/4000...01269453%22%7D
    Or arduino with GRBL.
    Or Linux based board.
    Or something like a uc400eth (best in my view).

    It all seems extreme but
    1 You want it to be reasonably good and be strong enough to cut aluminium.
    2. Give it a month or two and you'll move all this kit onto something bigger, so will need it!.
    3 Simple, pre-build, ready to go equipment, in the diy hobby world normally means..... Absolute CRAP!!!!
    In the controller list. I always forget to mention the AXBB-E as well.

  7. #7
    Registered
    Join Date
    Jan 2018
    Posts
    1041

    Re: Controller Advice Needed

    People rate these quite highly If you're planning to uae Mach3, Mach4 or UCCNC:
    https://cncroom.com/en/product-categ...terface-cards/
    Not exactly cheap though.
    However, they are more or less, All-in-one.

  8. #8
    Registered
    Join Date
    Mar 2017
    Posts
    913

    Re: Controller Advice Needed

    I cut aluminum and wood just fine with 465 oz/in and 381 oz/in stepper motors on 48v via a Gecko G540 with linuxcnc.

    They're more than capable of exceeding any feed rates I could realistically use and, breaking tools if I make a mistake. I do use 20mm lead ball-screws but I never use more than half it's top speed.

    I'd run into issues with stalling my 7.5hp spindle before running out of stepper power on my build.

    The choice of stepper should be based on the amount of weight it will move.

    If you're moving a lightweight aluminum table + a lightweight spindle, you can probably use 3.5a Nema 23 motors. If you're moving a 500lb+ cast iron knee or table on an old Bridgeport, you'll want 6a - 8a+ Nema 34's.

    With that said, it never hurts to get the best you can afford.

  9. #9
    Member
    Join Date
    Dec 2018
    Posts
    49

    Re: Controller Advice Needed

    Wow. Great information guys! I did not expect so much help. Much more help than the other forum I was on. I will read through these and research all the links when I get some time. I am sure I will have some follow up questions. Thanks!

  10. #10
    Member
    Join Date
    Dec 2018
    Posts
    49

    Re: Controller Advice Needed

    I am not apposed to running steppers other than 23s (although I want the best performance for my $) but the z-axis assembly I have coming has a nema 23 mount. The x/y axis's can be whatever as I have not figured out how I am going to mount them yet. I have received my 1605 ballscrews (1550mm) for them. The 400oz.in steppers linked above look like they might work well. Is there anything better that I should look at that has the same/better performance and price?

  11. #11
    Registered
    Join Date
    Jan 2018
    Posts
    1041

    Re: Controller Advice Needed

    Came across these:
    https://www.omc-stepperonline.com/ne...m-4-wires.html
    Theses look damn good on paper. (prob the best ones I've seen there amidst their rubbish!).

    I rate these drivers:
    https://www.omc-stepperonline.com/di...or-dm860t.html

    Throw in this supply:
    https://www.aliexpress.com/item/4000...1ba04c4dch0jTj
    Rated 60v 1000w per 4 motors.

    If you decide on a nema34 for say Z axis at all then up the supply to a 80v instead (only if using 110vmax drivers though, stick to 60v on a 80vmax).
    It will run them all giving great performance on the 34 and will not harm the 24's at the same time.

  12. #12
    Member
    Join Date
    Dec 2018
    Posts
    49

    Re: Controller Advice Needed

    Quote Originally Posted by joeavaerage View Post
    Hi,
    all steppers lose torque the faster they go, that's just the physics of how they work.

    Inductance (of the windings) is a good measure of how bad the torque degradation will be, the lower the inductance the better.

    Most newcomers do not understand inductance and focus solely on torque. A 800 oz.in stepper has got to be better than a 400 oz.in stepper right?
    If the 800 oz.in stepper has 8mH inductance its torque will drop off rapidly, probably only have 5% at 1000 rpm, that is only 40 oz.in. The 400 oz.in stepper
    on the other hand with an inductance of 2mH may have 30% of its torque at 1000 rpm, that is 120 oz.in. Thus you can see that the low inductance stepper outperforms
    the higher torque (with comensurately high inductance) at speed, so the machine would stall with the high torque stepper but carry on machining with the lower
    torque motor. Go figure!!!

    Stepper manufacturers know very well that newcomers focus on torque alone so they make steppers that have really great torque but shocking inductance....just to get the
    sale. Smart buyers know that a balance must be struck between inductance and torque.

    The classic method to minimise torque degradation with speed is to use high voltage drivers with a high voltage supply. I would strongly recommend both, if you buy well you'll have
    them for years......if you skimp you'll have to throw them out in a month.

    Craig
    Yeah I almost fell for the low quality kits. Glad I found this forum before purchasing. Thanks for the info.

  13. #13
    Member
    Join Date
    Dec 2018
    Posts
    49

    Re: Controller Advice Needed

    Quote Originally Posted by Goemon View Post
    I cut aluminum and wood just fine with 465 oz/in and 381 oz/in stepper motors on 48v via a Gecko G540 with linuxcnc.

    They're more than capable of exceeding any feed rates I could realistically use and, breaking tools if I make a mistake. I do use 20mm lead ball-screws but I never use more than half it's top speed.

    I'd run into issues with stalling my 7.5hp spindle before running out of stepper power on my build.

    The choice of stepper should be based on the amount of weight it will move.

    If you're moving a lightweight aluminum table + a lightweight spindle, you can probably use 3.5a Nema 23 motors. If you're moving a 500lb+ cast iron knee or table on an old Bridgeport, you'll want 6a - 8a+ Nema 34's.

    With that said, it never hurts to get the best you can afford.
    The Gecko looks like a nice unit. It looks like the support and warranty is top notch. The price seems a little steep. BUT I also like that they are here in the US. Although I am not against purchasing from China, I would rather purchase (even some of the highly recommended Chinese products) from a US based company mainly for warranty and support purposes.

    I will keep the Gecko in my list to compare.

    Thanks

  14. #14
    Member
    Join Date
    Dec 2018
    Posts
    49

    Re: Controller Advice Needed

    I want to apologize up front for my ignorance when it comes to all these controller/driver boards.

    When comparing boards and their features, what exactly am I looking for in a controller/driver board? All the different chipsets and technical info is like greek to me. I will (most likely) need a controller/driver board(s) to run one of the two following steppers.

    As for the steppers I am leaning toward the Nema 23 (400oz.in/1.8mH) from stepperonline or the Nema 24 (if I can find some that are not too expensive). The Nema 24s (that you linked to) are at about $60 vs $42 for the 23s. My budget for the electronics is now WAY over what I had originally planned for. Need to do what I can to keep it down where I can.

    Comparing these two stepper motors:

    Nema 23
    Manufacturer Part Number: 23HS33-4008S
    Motor Type: Unipolar/Bipolar
    Step Angle: 1.8 deg
    Holding Torque(Bipolar): 2.83Nm(400oz.in)
    Rated Current(Bipolar Parallel): 5.66A
    Phase Resistance(Bipolar Parallel): 0.4ohms
    Inductance(Bipolar Parallel): 1.8mH ± 20%(1KHz)


    Nema 24
    Manufacturer Part Number: 24HP39-5004S
    Number Of Phase: 2
    Step Angle: 1.8 deg
    Holding Torque: 3.5 Nm(495.74oz.in)
    Rated Current/phase: 5.0 A
    Phase Resistance: 0.48 ohms± 10%
    Inductance: 1.85 mH ± 20%(1KHz)

    Which one is better and why? Or are they pretty close in terms of performance? I am trying to determine if paying 50% more for the 24s is worth it.

  15. #15
    Registered
    Join Date
    Nov 2013
    Posts
    1478

    Re: Controller Advice Needed

    Hi,
    there is little to pick and choose between them.

    Earlier I posted that inductance largely determines how fast a stepper will go, that is a slight simplification, the true metric is the inductive time constant, which
    is the product of the resistance and the inductance.

    23: inductive time constant = 0.4 x 1.8 mH = 0.72 ms
    24 inductive time constant = 0.48 x 1.85mH = 0.888 ms

    Thus the 23 size stepper is slightly better in terms of its potential speed.

    '23' is a standard NEMA size and means 2.3 inches across the flats. '24' is not a standard size, it is about 2.4 inches across the flats, but is in fact exactly 60mm across the flats.
    24 size refers then to the metric equivalent of 23 size. A 24 will not fit in the hole for a 23 motor and vice versa.

    In hobby CNC circles Gecko have established themselves as the premier brand. There are in fact plenty of other Japanese, US and European brands that are as good or even better....
    but are even more expensive again! Look up Sanyo Denki or Vexta or Pacific Scientific and you'll see what I mean.

    If you are trying to conserve budget then the Chinese made DM860 that Dapz1976 linked to are great quality and reliability at half the cost of a Gecko. Supporting the 'home team'
    is a laudable reason for paying the extra however. Your choice.

    Craig

  16. #16
    Member
    Join Date
    Dec 2018
    Posts
    49

    Re: Controller Advice Needed

    Thanks Craig for the added explanations.

    So based on your numbers the 23s have a slight step up in terms of speed. Does the 24s have an advantage over the 23s in other aspects that would justify the additional costs? IF not then I guess it is kind of obvious to go with the 23s in this case?

  17. #17
    Member
    Join Date
    Dec 2018
    Posts
    49

    Re: Controller Advice Needed

    Does the Gecko include the controller board as well as the driver boards or is it just the driver boards all-in-one?

  18. #18
    Registered
    Join Date
    Jan 2018
    Posts
    1041

    Re: Controller Advice Needed

    The G540 is old tech.
    It's ran off pc parallel port which is obsolete or have to fork out for an extra controller.
    Is only 3.5A per axis.

    Waste of time putting this on those nice motors. They'll be crippled.

  19. #19
    Member
    Join Date
    Dec 2018
    Posts
    49

    Re: Controller Advice Needed

    Quote Originally Posted by dazp1976 View Post
    The G540 is old tech.
    It's ran off pc parallel port which is obsolete or have to fork out for an extra controller.
    Is only 3.5A per axis.

    Waste of time putting this on those nice motors. They'll be crippled.
    Thanks for confirming my thoughts on that.

    Here is where I am at so far...
    1. Nema 23s (400oz.in/1.8mH)
    2. DM860 Stepper Motors
    3. AC to DC 60V 16.7A 1000W Switching Power Supply


    Question: Will using these components allow me to get the most out of the motors? Is there any bottleneck that will hamper them? Not completely understanding the electrical piece I wonder if there is enough amps (current) coming from the PS to reach the full 5.6 amps per motor. My math shows that 4.166 amps is the max the PS can supply. Please correct me if I am understanding this incorrectly.

    Still need to figure out the controller board. Not real sure what I am looking for in one of these boards. I know you mentioned the Mach3 board, and that may be the way I go, but I kinda want to understand why I am choosing something. I don't have much experience building a CNC from scratch and piecing the electronics together. So I am not sure exactly what is needed and how I get it all working. I have used the Arduino Mega 2560 + v1.2b Shield that came with a Maslow CNC. It was super easy. I just plugged the unit it, loaded the G-code software on my old laptop, plugged the laptop into the Arduino and sent the file and started my projects. I am trying to understand how to get to that point with all these pieces.

    I appreciate everyone's patience and guidance. I guess everyone started here at one point.

  20. #20
    Registered
    Join Date
    Nov 2013
    Posts
    1478

    Re: Controller Advice Needed

    Hi,

    So based on your numbers the 23s have a slight step up in terms of speed. Does the 24s have an advantage over the 23s in other aspects that would justify the additional costs? IF not then I guess it is kind of obvious to go with the 23s in this case?
    Unless 60mm motors are required then no, the 23 size are faster and cheaper.

    Does the Gecko include the controller board as well as the driver boards or is it just the driver boards all-in-one?
    You might be confusing the G540 and the standalone single driver like the G203. The G540 has four drivers incorporated into it and a basic breakout board. Given its price
    and that it represents a near complete solution it is very popular. Unlike dapz1979 I don't regard them as a waste. They are limited to 50V, which is a little low in my opinion and limited
    to 3.5A and so your motors would be somewhat underdone but not disgracefully so.

    If you are going to make comparisons between the DM860 then you need to compare it to the G203....the G540 is a different animal. The G203s are about $131 each whereas the
    DM860 can be had for $50 and yet in practice they perform near identically.

    Craig

Page 1 of 7 123

Similar Threads

  1. Controller Advice needed
    By robwiacek in forum Servo Motors / Drives
    Replies: 0
    Last Post: 01-05-2018, 01:34 AM
  2. Advice Needed servo drives and controller software
    By Krebomatix in forum Servo Motors / Drives
    Replies: 0
    Last Post: 09-10-2017, 08:01 AM
  3. [ADVICE NEEDED] Z-Axis not moving - CNC builder needed
    By baodogg in forum Australia, New Zealand Club House
    Replies: 2
    Last Post: 06-03-2014, 12:42 PM
  4. Material advice and advice needed
    By kiyoukan in forum Mechanical Calculations/Engineering Design
    Replies: 0
    Last Post: 02-15-2012, 08:20 PM
  5. CNC Controller Advice Needed For homemade cnc mill
    By crashing in forum General CNC Machine Related Electronics
    Replies: 2
    Last Post: 06-26-2010, 09:12 PM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •