PNConf step scale calculation

Hi All,
           Just had an interesting calibration attempt.
Here is the scenario, X axis is driven by a 25 tooth 1/4-inch sprocket directly to a chain.
In the step calculator I set the following values:
Checked Pulley Teeth: 25, 25 
Microset Multiplication Factor: 125
Motor steps per revolution: 200

This gives a motor step per unit of 25000.
Testing this value nearly launched my x of the transom.

The DM542T is set to 25000 step/rev giving 125 microsteps per step.
Obviously, I am missing something here, can someone point me in the right direction

hirst689




 

A scale of 25000 only makes sense if the axis moves 1mm per sprocket turn

What is the pitch of the chain?

If its 1/4", that's ~1 inch of chain motion per sprocket turn so a scale of
984.251 (steps per mm)  would be closer
 

If the sprocket has 25 teeth and the chain is 1/4 inch, then surely one rotation of the sprocket should be 25 X 1/4 inch? That would be 6.25 inches (158.75 mm)
The outside diameter of the sprocket is 53.5mm that is a circumference of 168mm, I do not know the tooth bottom to tooth bottom diameter, but it seems about right.
I have the stepping scale at 200 and it seems to give a large movement for a 10mm jog, way more than 10mm.
Is a microstep setting on the DM542T excessive?
I am very confused by what I am seeing,

Hirst689

microstep setting is 25000.

Sorry 157.480 usteps per mm
(25000/(6.25*25.4))

Note that this is a really high gear ratio
and I would not expect accuracy better than
say 1/4 full step ~= 0.2 mm