CAD CAM EDM DRO - Yahoo Group Archive

Stepper motors are still going at the wrong speed........

Posted by apples0_17
on 2005-12-23 04:59:23 UTC
Ihave this system on a plasma table.

Cut area 3m x 2m
Geckodrive G202's
48Volt 13amp power supply
Running two 1200oz-in steppers on the x

axis.
And one 270oz-in stepper for the y axis.

Using CorelDRAW, AutoCAD, SheetCAM and

Mach3.

The motors are all tuned up right. They

have the correct steps per unit etc.

--------------------------------------------

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The problem:

If the velocity is set to 10,000mm/min in

the 'motor tuning' page for both the x and y

axis. And I go and jog the gantry in the y

axis it will move along at the correct speed

of 10,000mm/min. This will be shown in the

DRO.

But, if I jog with the x axis the motors

will move at 14,000mm/min instead of the

10,000mm/min that was setup in the 'motor

tuning' page.

This problem will also happen if I run a

g-code through Mach3. Say for example I run

a square shape. The feed speed will be set

on 5000mm/min. The y axis will feed

correctly at the set 5000mm/min. The x axis

will move faster than the set speed that it

is meant to. It will move at 7000mm/min

instead of the 5000mm/min required.

I have checked that the speeds that the DRO

are reading are correct.
How I done this was, Made the machine run

for a distance of 1meter and counted how

long it would take to travel the 1meter.

From those results it showed that the DRO

are giving me correct readings.

I have alos cut out a part in 10mm steel

with the plasma. You can see how the edges

are smooth and perfect, then the gantry

makes a right turn and the x axis starts

driving. The x axis moves faster than the y

axis and therefore the cut edge is very

poor.

I am only a newbie to this so I have tried

everything that I can think of.

I wiped all traces of Mach 3 then reloaded

Mach3 again. Making sure to re-boot after

the instalation.

So I am stumped as to what is going on.

Can anyone help?

P.s on the gecko's I adjusted a 'trimpot'

which is the 'low speed vibration' trimpot

screw. Maybe this has effected the motors

etc...
I adjusted the screw at the back of the

Gecko untill the vibration in my machine

went away.


Peter
Australia

Discussion Thread

apples0_17 2005-12-23 04:59:23 UTC Stepper motors are still going at the wrong speed........