[dmh13433]

I am hoping someone can help me. I want to drive two stepper motors from zero to 750 rpm together sycronized. I don't want to use a laptop. Is there a stand alone programmable driver that I can do this with? I would like to have a switch to turn them on and potentiometer that goes from zero to however fast I can get them.
I bought this kit and thinking instead of Mach3 and my current drivers. Maybe there is some other driver I can use?

【USA FREE】 2AXIS Wantai 1Axis Nema34 Stepper Motor 1700oz-in 151mm 6A CNC plase

This machine will have a string stretched between the two motors and I want to wind another string around the one stretched between while the motors are turning. It's called serving. Making strings and cables for compound bows.
Any help, I would greatly appreciate.

[tinmancarving]

Maybe something like this will work for you....

https://www.aliexpress.com/store/pro...711847030.html


Rob

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Edit: fixed link.

[Jim Dawson]

Any of these would work for what you want to do

stepper motor speed controller | eBay

Just wire the step & direction output to both drives' inputs, that will sync them.

[dmh13433]

thanks Jim
I have been told they will only work with one motor/driver. I guess it is cheap enough to buy one and try it.

[Clackneil]

That's actually an interesting way of serving a bow string. I used to make these by hand myself and I could see that being a real help, if you can get the tension to stay.

For your question, I personally would build a custom circuit to do this. As these steppers will only need to move one direction and at a constant set speed once adjusted.
May I ask ehy steppers and not any other type of motor?

After checking out Tim's option, if your not into building circuits, I'd definately try that out. For 20 bucks, I'd consider it worth a shot.

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[dmh13433]

Specialty Archery is selling a machine with steppers right now. If you use any other motor, I think you would need a driveshaft to go all the way to the other side with some gears or cog belts to keep the timing.(you have to spin the string without getting twist in the string). That would be lot more moving parts, gears, bearings and supports. Steppers seem to be cheapest and can still keep the string from twisting. I am trying to program an Arduino, but having trouble getting the speed over 350rpms and it stalls. I'm thinking maybe getting mach3 and see how fast I can get them to go.
it would be nice to have two programs. ONE- to turn on and off.....have potentiometer to control speed. TWO-have a counter to set how many turns then shut off, with potentiometer to control speed.
I will settle for just turning it on and off for now and control speed with potentiometer.

That's actually an interesting way of serving a bow string. I used to make these by hand myself and I could see that being a real help, if you can get the tension to stay.

For your question, I personally would build a custom circuit to do this. As these steppers will only need to move one direction and at a constant set speed once adjusted.
May I ask ehy steppers and not any other type of motor?

After checking out Tim's option, if your not into building circuits, I'd definately try that out. For 20 bucks, I'd consider it worth a shot.

Sent from my SM-G935V using Tapatalk

[Clackneil]

Specialty Archery is selling a machine with steppers right now. If you use any other motor, I think you would need a driveshaft to go all the way to the other side with some gears or cog belts to keep the timing.(you have to spin the string without getting twist in the string). That would be lot more moving parts, gears, bearings and supports. Steppers seem to be cheapest and can still keep the string from twisting. I am trying to program an Arduino, but having trouble getting the speed over 350rpms and it stalls. I'm thinking maybe getting mach3 and see how fast I can get them to go.
it would be nice to have two programs. ONE- to turn on and off.....have potentiometer to control speed. TWO-have a counter to set how many turns then shut off, with potentiometer to control speed.
I will settle for just turning it on and off for now and control speed with potentiometer.

Let me see what i can cook up for you in the next few hours (ideawise, that is)

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[Jim Dawson]

Specialty Archery is selling a machine with steppers right now. If you use any other motor, I think you would need a driveshaft to go all the way to the other side with some gears or cog belts to keep the timing.(you have to spin the string without getting twist in the string). That would be lot more moving parts, gears, bearings and supports. Steppers seem to be cheapest and can still keep the string from twisting. I am trying to program an Arduino, but having trouble getting the speed over 350rpms and it stalls. I'm thinking maybe getting mach3 and see how fast I can get them to go.
it would be nice to have two programs. ONE- to turn on and off.....have potentiometer to control speed. TWO-have a counter to set how many turns then shut off, with potentiometer to control speed.
I will settle for just turning it on and off for now and control speed with potentiometer.

Might also try one of these units. Can be programmed to run some number of turns then stop. I have one sitting on my test bench, but I havn't had time to play with it yet.

SainSmart 1 Axis CNC Servo Stepper Motor Motion Programmable Controller, New, Fr | eBay

[dmh13433]

Might also try one of these units. Can be programmed to run some number of turns then stop. I have one sitting on my test bench, but I havn't had time to play with it yet.

SainSmart 1 Axis CNC Servo Stepper Motor Motion Programmable Controller, New, Fr | eBay

Jim, do you know for sure this will work? If you try it and it works, I think I would buy that. Does it only work if you input in how many turns?

[Jim Dawson]

It has several modes of operation, I haven't really gotten too deep into it yet. I just bought it because I thought it was cool, and I might have a use for it one day. I have set it up on my test bench and played with it a bit. I know it will drive the motor some number of steps and speed that you program, and then by pushing another button it will reverse and go back to 0.

This is from their product description ''Manual operation functions: position adjustments (manual jog speed and jog the number of steps can be set" So that function sounds like exactly what you need for your application.

EDIT I found the manual for it http://www.variometrum.com/PDF/ST_PMC1_ENG.pdf

[dmh13433]

update on my project.
I got everything built except a box to hold power supply, and drivers.
Mach 3 is running the motors at 1,300RPM
Here is a link to an archery forum showing it, and a link to youtube video.

String Jig/Winder

[Tec22]

update on my project.
I got everything built except a box to hold power supply, and drivers.
Mach 3 is running the motors at 1,300RPM
Here is a link to an archery forum showing it, and a link to youtube video.

recurve bow string

Any luck with getting motors to go above 1300RPM or any downside to doing so?

[dmh13433]

Any luck with getting motors to go above 1300RPM or any downside to doing so?

here is a video of my completed project. I had help from hfjbuis on cnczone with the program. The guy is amazing programing an Arduino.
I only go 800 RPM. It will work faster, but not 1,300RPM I could probably go 1,000RPM. if you want to go much faster, I think you would need some gearing to step up the speed.

https://www.youtube.com/watch?v=mWyiAOYC3QI