A Dumb Idea? Stepper Motors As Power Feeds.

tomw

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Dear All,

I really don't know anything about CNC or stepper motors. Whew, I confess. But, I notice that these motors are very small. Can stepper motors be adapted to be a power feed for an axis? I am thinking of some simple controller that allows you to:

1) adjust the feed speed
2) change direction of feed
3) start and stop feed

One would have a CNC ready machine, but with the 'manual' controls of a typical power fed lathe or milll.

This would be beneficial for:

1) me
2) others?

I am thinking of X and Z axis power feed on the lathe, and X and Y axis power feed on the mill.

So, how badly have I embarrassed myself?

Cheers,

Tom

P.S. I don't need a safe space. Feel free to threaten my manhood due to my ignorance.
 
Dear All,

I really don't know anything about CNC or stepper motors. Whew, I confess. But, I notice that these motors are very small. Can stepper motors be adapted to be a power feed for an axis? I am thinking of some simple controller that allows you to:

1) adjust the feed speed
2) change direction of feed
3) start and stop feed

One would have a CNC ready machine, but with the 'manual' controls of a typical power fed lathe or milll.

This would be beneficial for:

1) me
2) others?

I am thinking of X and Z axis power feed on the lathe, and X and Y axis power feed on the mill.

So, how badly have I embarrassed myself?

Cheers,

Tom

P.S. I don't need a safe space. Feel free to threaten my manhood due to my ignorance.

Steppers are routinely used to drive a machine axis. They are made in many sizes. Check for posts here that address or describe what others have done.
 
No reason that you can't run a stepper manually. Just select one with enough torque to run your feed. The steppers on my Tormach 770 are Nema 34 500 oz-in. torque. Your requirements may differ, depending on the size of your mill.
 
Cool. Thank you for the information.
tomw, I would also do some research on the 3d printing front.

Stepper motors are key in running a quality 3d printer. There is an open source collective known as the RepRap community. This collective specializes in building 3d printers from scratch. I would imagine there is a treasure trove of info about the best stepper motors and how to control them. Best of all its open source!! You can use an arduino with a stepper shield to control a motor, then get fancy with it and make it Bluetooth enabled or something. The possibilities are endless.
I will be happy to answer any of your 3d printing questions in the future, I have been printing for about 5years now and have just ventured into machining. But I don't want to intrude, seeing how this is a machinist forum and not a 3d printing forum.

P.S. RepRap stands for Replicating Rapid Prototyping

Thanks

Sent from my XT1097 using Tapatalk
 
I'm thinking about motorizing the X axis on my mill in a similar way - with a simple manual system (left, right, stop push buttons buttons and a speed control pot), plus a couple of moveable limits so it can automatically change direction and move back and forth between two positions (say, while I manually feed the Y axis each time it changes direction).

My thought was for a simple system like this a dc motor would be more suitable, and using a stepper motor would over complicate it. Stepper motors are great if you want to keep track of position (i.e. moving a fixed distance can be controlled but sending a fixed number of steps). But if you just want simple movement and speed control a dc motor can be used without the need for all the control electronics (and expense) needed to control a stepper motor.

Obviously of you want to do it as a stepping stone towards full cnc control them using a stepper motor is the way to go. But if the system you describe is the end result I think it can be done simpler with a dc motor.
 
I'm thinking about motorizing the X axis on my mill in a similar way - with a simple manual system (left, right, stop push buttons buttons and a speed control pot), plus a couple of moveable limits so it can automatically change direction and move back and forth between two positions (say, while I manually feed the Y axis each time it changes direction).

My thought was for a simple system like this a dc motor would be more suitable, and using a stepper motor would over complicate it. Stepper motors are great if you want to keep track of position (i.e. moving a fixed distance can be controlled but sending a fixed number of steps). But if you just want simple movement and speed control a dc motor can be used without the need for all the control electronics (and expense) needed to control a stepper motor.

Obviously of you want to do it as a stepping stone towards full cnc control them using a stepper motor is the way to go. But if the system you describe is the end result I think it can be done simpler with a dc motor.
What kind of DC motor are you planning to use, how would you handle the speed control? As far as I know, unless it's some kind of DC Servo it won't have much low speed torque which is what you need for a power feed. You could use a gear reduction with motor but by that time, I think, the complication/cost would be on par with using a stepper or DC servo motor with a driver.
 
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In my situation I will need a couple of gears (or a belt drive) to connect from the motor mount to the lead screw anyway - the mill already has a mounting flange arrangement below the leadscrew on the leadscrew bearing plate at the opposite end from the handle. So yes I was planning to have reduction gear.

I have a couple of 24Vdc, 100W, 2700rpm motors from an old automatic gate opener and was planning to try and use one of those. A 10:1 gear reduction (my initial guess, still have to work out what number of teeth, DP, etc that will work in the space available) would give me a max table speed of around 1250mm/min with my lead screw and speed control would just be by reducing the motor voltage.

Maybe a stepper motor wouldn't be so complicated if you could source a suitable stand-alone controller/driver that just took the necessary control inputs. My (limited) experience with them has always been with a driver board, then a breakout board, then a PC with controller software which would obviously be overkill for the system proposed. My proposed control design requires only 3 push buttons, three relays and a potentiometer.
 
In my situation I will need a couple of gears (or a belt drive) to connect from the motor mount to the lead screw anyway - the mill already has a mounting flange arrangement below the leadscrew on the leadscrew bearing plate at the opposite end from the handle. So yes I was planning to have reduction gear.

I have a couple of 24Vdc, 100W, 2700rpm motors from an old automatic gate opener and was planning to try and use one of those. A 10:1 gear reduction (my initial guess, still have to work out what number of teeth, DP, etc that will work in the space available) would give me a max table speed of around 1250mm/min with my lead screw and speed control would just be by reducing the motor voltage.

Maybe a stepper motor wouldn't be so complicated if you could source a suitable stand-alone controller/driver that just took the necessary control inputs. My (limited) experience with them has always been with a driver board, then a breakout board, then a PC with controller software which would obviously be overkill for the system proposed. My proposed control design requires only 3 push buttons, three relays and a potentiometer.

You don't need a PC to run a stepper, just the motor, a drive, and a pulse generator. I have a couple on the shelf that I use for testing systems.

From my post above:

You can use one of these to run the stepper manually http://www.ebay.com/itm/Stepper-Mot...d87660&pid=100338&rk=6&rkt=26&sd=281570110066

Or a little more sophisticated, with drive,
http://www.ebay.com/itm/Reversible-...d=100338&rk=8&rkt=26&mehot=pp&sd=281570110066

Or even with remote control,

http://www.ebay.com/itm/Adjustable-...87660&pid=100338&rk=11&rkt=26&sd=281570110066

And this controller will give you almost 100% torque at zero RPM with a DC motor
http://www.ebay.com/itm/MAX-10-50V-...689235?hash=item2ee45b6013:g:w1kAAOSwHnFVvr2I
 
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