Help! Stepper stalls high speed problem?

First post and wish i had found this forum a few months ago 

They say stepper motor suppliers love newbies

I have a Warco wm18 mill and have added a power z axis stepper but it stalls at high speed



I have set the driver to 4.2a and i think, can't remember without opening enclosure, to 1600 steps/rev

It works quite well but tends to stall at max speed especially raising the head. For info the head does have a gas strut helper

so where have i gone wrong?

I think decreasing the speed will solve your problem ...

But if seriously - you give not to much information to understand more... Attach please configuration files for your servos.
What maximum speed you have? Does steppers are configured right?

I have converted 2 WM18s 
In my opinion nema 17 are a bit small . I would use nema 23 with a drive that will handle at least 60V so a bigger power supply as well.
Welcome to the forum .
 

24v for motors is not enough. I learnt the hard way too. The motors are only 1.5 amps so don't exceed that.
Doubling the voltage will quadruple motor torque. Look for a 48v power supply for your stepper drivers. Say 7-10 amps
Try that first but I suspect you will need to upgrade the motors as stated earlier. At least you will have the drives and power for them.
I know a friend with a very early Syil which was based on a Seig SX3 which is a similar size. It uses a NEMA34 on the Z axis.... and NEMA 23's for X & Y

Nema 17 is to small, it says extruder motor on the link.
@RodW
Doubling voltage does not quadruple torque on stepper systems, it raises the usable high end RPM by a lot.
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As mentioned, use a Nema 23 stepper, try to find a low inductance one, those are much better for higher speeds and can be used with 24V for most applications.

tommylight wrote:

@RodW
Doubling voltage does not quadruple torque on stepper systems, it raises the usable high end RPM by a lot.
 

And increases power and torque 
www.geckodrive.com/support/motor-power
Where the OP is in the journey, its easier for him to increase the power supply voltage than to make new mounts for his existing motors. He will get improved performance but whether it is enough is another matter.

On my first stepper project, I used 24 volts and suffered from lost steps. Replacing the power supply with a 48 V one solved that due to increased power and torque offered,

There is a lot less work following my suggestions  v's replacing motors and the higher voltage will also get better performace with NEMA23's. Long term he probably needs to do both but he might get some improvement quite easilly by changing the power supply, Who knows, that may let him machine some nice mounts for nemaa 23's too.