They are too expensive related to A4988.
what is the cost of failure ?
the a4988 only costs about $5 and you can drive your motor.
time to order the unit, install it and test it.
you are never going to find the answers on a web page, a data sheet or a forum.
the only place you will find the answer is on your device, in your shop.
would you rather use a $300 linear bearing with the lowest cooefficent in order to use a $3 driver because the $3.25 driver cost too much ?
what will you say if you put on the motor and find the $3.25 driver and motor have 5 times more torque than you need ?
the power of the motor is often used to overcome the poor design of the device. the first mechanical iteration shows the possibility of operation, the second shows the refinement of both over design and under design. be happy if version 5 works flawless. be happier if your first design can actually be built and works at all.
sounds like you are an engineer who wants to know everything before actually doing anything.
and, in the end, if that $5 driver is wrong and underpowered, you will still find uses for it. there are just too many times you want to grab something to try it out and use whatever is at hand.
if you truly only want to build it once, then buy the Gecko 201 vampire. at $143 it WILL power your motor. no questions.
also buy a matching power supply. should not cost over $100. but you are guaranteed that if a stepper can work in that application, that combination will drive it.
spending $5 on the driver you would be KNOW already. this whole thread is really about a part that may cost $15. without any actual measurements, no tests and unknown quantities.
Sorry if I seem abrupt, but this thread is going around in circles and has been answered WITHOUT any actual data.
what is the load ? what is the MEASURED force needed ? how are you driving, belts ? gears ? screws ?
what PROBLEMS with your device are you EXPERIENCING ?
it started on June 27 and it appears that no project is being built and the same questions are being asked. what is the force needed to drive your machine ?
by this time, parts could have been ordered, arrived, the device built and troubleshooting underway.
if your machine is ever going to be built, then build it, tie a string on the pulley and add weight until it moved. calculate force and you do not have to keep others guessing about what is the color of a flower in a room without light.