554,259 active members*
3,922 visitors online*
Register for free
Login
IndustryArena Forum > WoodWorking Machines > DIY CNC Router Table Machines > I want to add a high speed 4th axis, Will a servo motor run at high speeds?
Results 1 to 7 of 7
  1. #1
    Neuer Benutzer
    Join Date
    Jan 2013
    Posts
    222

    I want to add a high speed 4th axis, Will a servo motor run at high speeds?

    I want to add a high speed 4th axis on my machine to use like a lathe. To get clean cuts I need to spin the workpiece up to 3000 rpm (I think). It will also need to have a decent amount of power as I'd like to spin some alrger pieces, up to 20 lbs. I don't know anything about servo motors. My questions are:

    Can a servo motor spin this fast?
    How big a motor do I need?
    Can the motor speeds go as low as 1 rpm up to 3k?
    will the motor maintain positional accuracy at all it's speeds?
    Where can I learn about servos and configuring them?

    I went down this road because I got a SEM MTS30M4-48 servo motor for free. I do not have anything else other than the motor. Would this motor work?

  2. #2
    Member
    Join Date
    Nov 2020
    Posts
    361

    Re: I want to add a high speed 4th axis, Will a servo motor run at high speeds?

    small servos 60-110mm spin 3000-2500 and the bigger you go the slower they get, you'd have to compute how much torque you need to spin 20 lbs at 3000 rpm plus machining load and then you can go and search for a servo, at this high speed though the torque gets really small. Also the pieces diameter matters too because you wanna know how much N is at the circumference, servos specs are in Nm so you have to convert it.

    are you sure you need 3000? the range on mill turns is usually around 300-800RPM and they do just fine.

    Since you already have a motor I'd make a good stiff housing for the components and then just see how far you can go with what you have. You can make it future proof as well so that you only have to upgrade the servo when needed.

  3. #3
    Community Moderator Al_The_Man's Avatar
    Join Date
    Dec 2003
    Posts
    23976

    Re: I want to add a high speed 4th axis, Will a servo motor run at high speeds?

    Are you talking about a Live Axis?
    Usually the X axis on a lathe.
    Although it sounds as though you want to spin the part like a lathe chuck, not so clear what you are doing? You also mention positioning?
    The three axis that rotate around the X,Y,Z are noted as A,B,C axis.
    What is the nature of the present machine?
    AC servo motors can easily achieve 3krpm.
    CNC, Mechatronics Integration and Custom Machine Design

    “Logic will get you from A to B. Imagination will take you everywhere.”
    Albert E.

  4. #4
    Community Moderator Al_The_Man's Avatar
    Join Date
    Dec 2003
    Posts
    23976

    Re: I want to add a high speed 4th axis, Will a servo motor run at high speeds?

    That motor looks as though it is DC brushed so limited to around 2krpm-2.5k5rpm tops.
    CNC, Mechatronics Integration and Custom Machine Design

    “Logic will get you from A to B. Imagination will take you everywhere.”
    Albert E.

  5. #5
    Community Moderator Jim Dawson's Avatar
    Join Date
    Dec 2013
    Posts
    5601

    Re: I want to add a high speed 4th axis, Will a servo motor run at high speeds?

    Quote Originally Posted by TTalma View Post
    I want to add a high speed 4th axis on my machine to use like a lathe. To get clean cuts I need to spin the workpiece up to 3000 rpm (I think). It will also need to have a decent amount of power as I'd like to spin some alrger pieces, up to 20 lbs. I don't know anything about servo motors. My questions are:
    Can a servo motor spin this fast?
    Yes

    How big a motor do I need?
    Good question, it depends on the required torque for the operation

    Can the motor speeds go as low as 1 rpm up to 3k?
    Yes. That type of motor should produce near full torque from 0 to near max RPM.

    will the motor maintain positional accuracy at all it's speeds?
    With the right controller it will be pretty close. However for a spindle drive, positional accuracy is not normally a factor until you are doing indexing, or rotary axis profiling, which is normally done at reasonably low speeds.

    ........Would this motor work?
    Maybe, depends on how much torque you need. The torque requirement depends on how much material you are trying to remove at one time, and the diameter of the workpiece.

    Based on the scant information available for your motor it looks like it is about 1HP and has a maximum RPM of about 2900. As near as I can tell, the -48 means 48 volts/1000 RPM. It's a brushed DC servo motor.
    Jim Dawson
    Sandy, Oregon, USA

  6. #6
    Neuer Benutzer
    Join Date
    Jan 2013
    Posts
    222

    Re: I want to add a high speed 4th axis, Will a servo motor run at high speeds?

    Thanks for all the feedback. It sounds like what I have may not be ideal. I injured my shoulder and will be out of the shop for a few weeks. This should give me some time to do more research and figure out what I need.

  7. #7

    Re: I want to add a high speed 4th axis, Will a servo motor run at high speeds?

    4 th axis , do you have find rotary ? such as chuck size ,diameter ,length ?

Similar Threads

  1. Replies: 2
    Last Post: 12-16-2018, 04:25 PM
  2. High Speed Spindle Add-On
    By RTP_Burnsville in forum Tormach Personal CNC Mill
    Replies: 9
    Last Post: 01-23-2017, 02:37 AM
  3. Help. HobbyCNC 3 Axis, Want To Add 4th using Servo Motor.
    By PatrickMM in forum General CNC (Mill / Lathe) Control Software (NC)
    Replies: 0
    Last Post: 04-14-2012, 07:53 PM
  4. High Torque , High Bandwidth Motor or Servo
    By mastabib in forum Benchtop Machines
    Replies: 0
    Last Post: 09-26-2007, 08:09 AM

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
  •