diffrent x axis problem

[hornby chopper]

Hi every one had my nm-200 running today and the problem has gotten worse.

my x axis is feeding to the x+ side of the table further with every cut but the counter keeps reading the same numbers that it's to run at.

( stepper maybe missing some counts in one direction )

i have been having a problem with the x axis just stop feeding and the counter keeps going

what are the thoughts out there.

the z and y axis are fine

[ihavenofish]

a few possibilities.

1: you have a loose wire on the stepper drive for that axis and its intermittently disconecting.

2: the drive isnt recieving a good pulse train from the PC. if its not stalling (making noise) you can try chanding to "sherline mode" in porst and pins. this extends the pulse width and sometimes makes the drives happier. ive had to do this on a few machines, incuding the nm200. this is a geckodrive issue technically.

3: if it IS, making noise when its loosing position, it can be the stepper timing as above, your speeds or acceleration could be too high, gibs too tight, or even the program if its complex contouring (mach3 has some issues with special cases).

so, a few questions.

is it making stall noises?
it it losing position in the same spot every time?

[hornby chopper]

thanks for repling

not making any noise and it looses about 0.040 to 0.050 on a pass

dos not seam to stall out when it is loosing stepps

it will on the first start of the day run x axis 10" maybe then just stop

then reboot the system and go .

i will look at loose connections in the morning.

how mutch torque shude it take to tourn the x axis with stepper connected and how hot should the get running at about 9" per minute

thanks

[ihavenofish]

thanks for repling

not making any noise and it looses about 0.040 to 0.050 on a pass

dos not seam to stall out when it is loosing stepps

it will on the first start of the day run x axis 10" maybe then just stop

then reboot the system and go .

i will look at loose connections in the morning.

how mutch torque shude it take to tourn the x axis with stepper connected and how hot should the get running at about 9" per minute

thanks

heat on a stepper is more or less constant no matter if its moving, loaded, or idle. the nm200 motors should have in the 5-10nm torque range at stall, maybe even more. if its stoppable or movable by hand, then theres something wrong.

[Dynoray]

thanks for repling

not making any noise and it looses about 0.040 to 0.050 on a pass

dos not seam to stall out when it is loosing stepps

it will on the first start of the day run x axis 10" maybe then just stop

then reboot the system and go .

i will look at loose connections in the morning.

how mutch torque shude it take to tourn the x axis with stepper connected and how hot should the get running at about 9" per minute

thanks

Hi Hornby, the first thing I would check is X axis ball screw for binding.
Power down the mill, then turn the "hand wheel" on the left end of the X ball screw. It should turn freely, you will feel the cogging of the stepper.
The NM-200 doesn't have a bearing or even a bushing on the floating end (left side) ball screw mount. So if you haven't replaced the mount already with a bearing unit or at least taken it apart and greased it with in the last few hours of use, it will bind up.
If you don't find that is the problem, power back up and "0" the X axis at a point and then jog back and forth until it misses steps (when your zero point is no longer zero)
If the stepper is missing steps, you'll hear a "stripped gear" sound when it does.
If you don't hear the "stripped gear" sound, but X zero is no longer where you zeroed it and the axis hasn't stopped working all together, then your X axis ball screw to stepper coupler is loose.
If the axis stops working all together, open the rear panel and remove the screws from the center to right side of the upper left aluminium pannel (4 screws I think), it is hinged on the left side of the pannel and once you remove the screws it will hinge open so you can see the Gecko's. Look and see if you have any red lights on (the far right Gecko is the X axis)
If you have a red light, it means the gecko has faulted. If this is the case, there's a good chance it's a connection where the screw terminals (green) plug onto the pins of the gecko's.
These are just some of the problems I have had and the solutions to them.
Hope it helps.
Ray

[hornby chopper]

Hi i got at it today and i found that if the ground wire is hooked up it will fault the drive. the screws holding the wire housing on the stepper were to small and you could just pull them out as soon as i put on right size screw in in faulted constantly. thanks for the support guys .

so i think there is a short in on set of windings or wire in the stepper.

still any more ideas for me to check please keep them coming


thanks to all

[ihavenofish]

Hi i got at it today and i found that if the ground wire is hooked up it will fault the drive. the screws holding the wire housing on the stepper were to small and you could just pull them out as soon as i put on right size screw in in faulted constantly. thanks for the support guys .

so i think there is a short in on set of windings or wire in the stepper.

still any more ideas for me to check please keep them coming


thanks to all

try the easy things first. set mach to sherline mode under ports and pins and see if anything changes.

[Dynoray]

Hi i got at it today and i found that if the ground wire is hooked up it will fault the drive. the screws holding the wire housing on the stepper were to small and you could just pull them out as soon as i put on right size screw in in faulted constantly. thanks for the support guys .

so i think there is a short in on set of windings or wire in the stepper.

still any more ideas for me to check please keep them coming


thanks to all

You might want to try swapping out the screw terminal from the X and Y axis to see if it's a pin connection problem. The green screw terminal slide straight on to the pins of the gecko (pull straight towards you to remove). I had a bad one that didn't contact the pin fully and it would fault the driver constantly.
Ray

[hornby chopper]

Hi and thanks for the info found out the x axis coupling was just to big for the shaft machined it out and bushed now go and tight.

for the faulting of the drive it was the screws on the stepper connector housing were putting to mutch pressure on the ring in side of the motor causing the fault when the cable was draging in one direction.

got new stepper from novakon and it has been running for about 1 hour now and no faults.

thanks to rodney and khai at novakon and every one here at the zone