Q1. I have stepper rated at 2.9V and 1.7A (Model: STP-57D113 ) Whats the best driver for it. Easy driver will not have that much current or can it handle it ?
Q2. Its a stepper with 6 leads so whats the best config for a CNC ( uni / bi ) ?
Q3. Why i can't just use 2xH bridge with GRBL (2 run steppers ) whats the limitation ? Is there some limitation or it wont even work ?
Q4. I have dagu mini driver that has Atmega8. Can it handle GRBL ?
Q5. Any substitute to GRBL ( As far as software part is concerned ) ?
If i am missing any details that should have been provided please ask
Details if someone interested
Just started on making my first CNC.
M not that good financially so m trying to keep things as much low cost as i can.
Visited the local junkyard and found two steppers there to start with. Both had stickers worn out so didn't know what their model was. some part of sticker of one motor was visible so after googling i found it to be Model: STP-57D113. The other one is still unknown though its exactly identical to the first motor the only diff is the shaft is a bit shorter rest all is same. However m sure the manufacturer is different as its remaining part of sticker was diff. Voltage and current ratings might be different as well but m not sure neither i have any idea how to find that out.Also if someone can get me the datasheet of Model: STP-57D113 cause i was unable to find it on google Any idea Guys ?
I tested both are spinning fine so far but i tested using L293D which cant give enough current so they were humming. Though the humming might be due to some other reason but i think of the current limitation.
Use a Pololu DRV8825 or, 2nd best, a Pololu A4988 or BigEasydriver (which also uses the A4988). The DRV8825 can handle a little more current. These are all bipolar drivers so you need to connect to 4 of the motor wires and leave the other two (the centre taps for the two coils) unconnected.
Specialized stepper motor drivers allow you to power the motor with a high voltage and significantly reduce the computational load on the Arduino.
Beret21:
Q1. I have stepper rated at 2.9V and 1.7A (Model: STP-57D113 ) Whats the best driver for it. Easy driver will not have that much current or can it handle it ?
Q2. Its a stepper with 6 leads so whats the best config for a CNC ( uni / bi ) ?
Q3. Why i can't just use 2xH bridge with GRBL (2 run steppers ) whats the limitation ? Is there some limitation or it wont even work ?
Q4. I have dagu mini driver that has Atmega8. Can it handle GRBL ?
Q5. Any substitute to GRBL ( As far as software part is concerned ) ?
If i am missing any details that should have been provided please ask
Details if someone interested
Just started on making my first CNC.
M not that good financially so m trying to keep things as much low cost as i can.
Visited the local junkyard and found two steppers there to start with. Both had stickers worn out so didn't know what their model was. some part of sticker of one motor was visible so after googling i found it to be Model: STP-57D113. The other one is still unknown though its exactly identical to the first motor the only diff is the shaft is a bit shorter rest all is same. However m sure the manufacturer is different as its remaining part of sticker was diff. Voltage and current ratings might be different as well but m not sure neither i have any idea how to find that out.Also if someone can get me the datasheet of Model: STP-57D113 cause i was unable to find it on google Any idea Guys ?
I tested both are spinning fine so far but i tested using L293D which cant give enough current so they were humming. Though the humming might be due to some other reason but i think of the current limitation.
stepper motor voltage is only the maximum you can use in a dead short.
the L293 is a CHOPPER style driver and you can use up to about 24 volts with it.
if you have it connected already, just put 12VDC power to the driver power pins, and try again.
the Dagu is a controller, first and has power transistors to switch loads. it does not have the circuits needed to act as a chopper driver.
the ones Robin2 mentioned are a step easier to use than the L293, they only use 2 pins, not 4, one for your step pulses, the other for direction. another thing about those Robin2 mentioned is that they can do microstepping.
microstepping is not micro-POSITIONING, the micro-steps only offer a smoother movement at lower speeds.
but, what you have are near the top of the line for hobby motors. low voltage, high amps, for hobby motors.
what makes them so great is the low voltage. the ratio between the voltage you feed them and the rated voltage sorta/kinda the force multiplier. if you bought the exact same amps, same model, but with a 12v rating, then you would need to feed them about 48 volts to get the same performance these will deliver with 12 volts. (4:1)
do not expect any better performance from the A4988 or DRV8825 at full or half steps
only a benefit is the 2 wire interface and the larger variety of microstep options.
but they will offer a smoother ramp if you use microstepping.
Beret21:
Q1 n Q2 are completely solved by your Stepper motor guide thanks for that.
actually the guide is very biased against the L293.
There are no actual performance gains, and if you have the L293 running, try it with 12 volts.
then buy one of the other drivers and try that.
ease of use for a newbee makes them preferred.
dave-in-nj:
actually the guide is very biased against the L293.
There are no actual performance gains, and if you have the L293 running, try it with 12 volts.
then buy one of the other drivers and try that.
ease of use for a newbee makes them preferred.
Thanks for replies i really love when someone help another.
As far as L293 is concerned i am just worried about the current limitation as my motors will be requiring 1.7A per phase and total would be 3.4A i guess ( m not sure if we just simply double it like that ) While the L293D can deliver a max of 600mA per channel. One IMP thing i want to know is that while i was trying an example to check my steppers with Arduino UNO and L293. If i gave Vcc(Motor voltage to L293D i.e voltage to pin 8) it made the motor to stop and hanged my arduino just like it was shorting something but as soom i remove the voltage from 8th pin the motor rotate fine !
I understood that voltage is not a concern for steppers that much as current is.
Also i read that torque suffers a lot when micro-stepping is increased ( m not that concerned about it atm )
I just want to get a cheap stepper driver atm. As the drivers like DRV8825 will cost me 3 times more then L293.
I can even buy L298 that will solve my current limitation but the major issue is GRBL. I really hate coding stuff and all that so i really do not want to get into software troubles as H bridges are not supported but if there is a chance to get H-bridges work with GRBL i will try my best but i really need someone to tell me if its even possible.
One more question regarding CNC. I want to go for 2x2 feet CNC what would be best timing belts or threaded rods i need an advice on this too.
as for you question about altering voltage. a stepper driver has two major sections.
the high voltage, high current section and the logic section.
as far as the Arduino is concerned, the logic is is either 5v or 3.3 volts.
as far as the power side, most of the driver chips in the hobby sector can run up to about 24 volts input.
an industrial version will run up to about 70 volts. as you put more power into a stepper it gets hot, cooking eggs hot.
wasted heat and all that. so steppers have a definite limitation on size.
post a link to your data sheet, the board may need to share grounds externally or may have an internal reference.
As for the current, everything is driven by APPLICATION. the reason they make small and large steppers is because every application needs to be properly sized.
if your stepper, running at 0.6A and 24 V works perfect, then all is good.
if you want to run at at 12v, but need to run it at 2 A, then you have to get a different driver.
if you are buying a different driver, would HIGHLY recommend you follow Robin2's preference for 2 wire drivers. one for step and one for direction.
my point is that if what you have now can work, make it work. if you find it is under powered, then you have to do something to get more power. higher voltage is one option, more current is another.
nathancamp:
I can't give an expert answer, but I can tell you what I am doing.
I'm using ball screws not timing belts. I plan on having roughly 5 ft x 3 ft of travel.
I don't think that timing belts can stand torque generated by 1/2 hp or higher motor.
timing belts are chosen for power. if you need to use them on a simple 100 hp motor, you just select the correct size.
not sure of how much HP a Harley Davidson SuperGlide delivers to the back wheel, but the timing belt they use seems to work fine.
also, laser cutters that run 3 meter x 5 meter tables at over 100 IPS travel have to use timing belts because of speed (APPLICATION) because you cannot get ball screws that large at a price you want to pay, nor spin them fast enough without vibration. and because timing belts are so easy to use. mechanical gear racks are also used, but it often the builders choice.
dave-in-nj:
as for you question about altering voltage. a stepper driver has two major sections.
the high voltage, high current section and the logic section.
as far as the Arduino is concerned, the logic is is either 5v or 3.3 volts.
as far as the power side, most of the driver chips in the hobby sector can run up to about 24 volts input.
an industrial version will run up to about 70 volts. as you put more power into a stepper it gets hot, cooking eggs hot.
wasted heat and all that. so steppers have a definite limitation on size.
post a link to your data sheet, the board may need to share grounds externally or may have an internal reference.
As for the current, everything is driven by APPLICATION. the reason they make small and large steppers is because every application needs to be properly sized.
if your stepper, running at 0.6A and 24 V works perfect, then all is good.
if you want to run at at 12v, but need to run it at 2 A, then you have to get a different driver.
if you are buying a different driver, would HIGHLY recommend you follow Robin2's preference for 2 wire drivers. one for step and one for direction.
my point is that if what you have now can work, make it work. if you find it is under powered, then you have to do something to get more power. higher voltage is one option, more current is another.
Thankyou for the detailed answer.
As far as motors data sheet is concerned i didn't find it any where. The only thing i know are some basics specs and i found them on only 1-2 sites on the whole WWW. These seem to be pretty rare motors. And this is the story of one motor. The other stepper is apparently same from outside as well as inside but its model/ spec sticker was almost completely worn out so i know nothing about it (Though i am sure that its not the same model/ manufacturer as the other stepper )
This is the one i know about and its all i know
model : stp-57d113
• current 1.7 A
• voltage of 2.9 V
• 1,8 deg/step
• pin 6 wire
• body length 39 mm
• width / height 56 mm
• total length 68 mm
• axis diameter of 6 mm
• 16 mm diameter of the rack
• weight 0.40 kg
dave-in-nj:
timing belts are chosen for power. if you need to use them on a simple 100 hp motor, you just select the correct size.
not sure of how much HP a Harley Davidson SuperGlide delivers to the back wheel, but the timing belt they use seems to work fine.
also, laser cutters that run 3 meter x 5 meter tables at over 100 IPS travel have to use timing belts because of speed (APPLICATION) because you cannot get ball screws that large at a price you want to pay, nor spin them fast enough without vibration. and because timing belts are so easy to use. mechanical gear racks are also used, but it often the builders choice. https://www.youtube.com/watch?v=7XwM_azm1so
I may have misspoke. I agree that belts can drive heavy loads. I see 400 hp motors driving agitators with a belt all the time. My concern is with the belt stretching or flexing when the cutter goes into the material it is cutting. Laser cutters, 3-D printers, and all applications that do not fight back are fine for belts (actually preferred).
Take a plunge router and plunge the bit into plywood and try to move it in a straight line (without a straight edge). The spinning bit will try to move away from where it is cutting making the router want to move side to side instead of front to back. You could probably find a belt strong and stiff enough by sacrificing flexibility and size, but that would require larger pulleys and belt drive gears.
While cutting, the acceptable feed rates will be much lower than the speed limit imposed by the ball screws, so the speed of movement is not my primary concern.
This is the reason I decided to use ball screws over timing belts for my project. The belts would have been much cheaper (I have ~$400 just in the ball screws).
Need advice about the threaded rods's diameter. What should be the diameter to avoid flexing for a 27" rod. I am getting deeper into CNC and at every step down there is something new to learn
I am going with the DRV8825 as suggested by robin. The current is good and its supports GRBL but will cost a bit but i think it worth it.
Update : I was able to run my steppers just fine after a lot of research and hit n try.
All the questions i started this thread for are answered / solved.
I went for A4988 Reason is that the steppers i have are all rated under 2A which this board can and is handling well. ( I set the current limit according to my steppers ) and these are much cheaper then 8825 here.
I was also able to find the model n info regarding the stepper whose sticker was worn off ( Unknown stepper motor )
It took me a whole week to find em out. The best way u can get info regarding any unknown motor is to search by specs that can be known easily like height length width ( face plate ) weight colors of wires it has ( helps only in case has more then 2 off course ) Write all these specs in google images and hope u will be able to find.
I would like to thank Robin2 and dave-in-nj for their time n for pushing me in the right direction and thanks to everyone else too who help me with my issues here.
