[stk2008]

Hi all ive finaly done it all be it less limit switches so i have only joged very very carfully.

i have an issue with only the y axis it keeps stalling all the others work great not one prob but just the y axis.

ive not done a hell of a lot as im tired and just got it to this point but realy want to hear a few reasons as to why they do it.

all of my motors are the same so is the drivers there for they are all tuned to the same in mach 3....cant remember the settings will post during weekend.

im just confused as its only that one axis that is doing it.

[ger21]

Could be that there's slight misalignment. Could be that the nut is tighter. Could be that the screw is bent slightly. Could be resonance. Could need lubrication.

Post a pic of your machine, and what drives, power supply, motors, screws, and nuts your using. What are your velocity and accel settings? What speed does it stall at?

[stk2008]

hi cheers for input

yes the trapezoidel spindle is a bit bent but i can turn it from one end to the other with me hand tho and these are very big motors so even a little stiffness shouldent stop these buggers.

you say vibration can do this ummmm ok will look into that as they do vibrate a fair bit but then so do all the other axis and there fine.

heres me other post im on wrong pc i have no pics at moment

http://www.cnczone.com/forums/showthread.php?t=89586

http://www.cnczone.com/forums/showthread.php?t=68626

edit sorry and motors

http://www.motioncontrolproducts.com...per-motors.pdf

im not sure how smooth or what noise motors should make etc mine do feel a little grindy when i hold them but they see to run ok?.

cheers

[pminmo]

Is the stall when moving it slowly or rapidly?

[stk2008]

hi i will be honest ive not done much testing as i was on it from 6:00am till last night and i was tired ive been on it none stop at those times for about a week now hehe.

ive only tested it on rapids and thats when it does it not every time but most

[pminmo]

what is the screw pitch? how fast is the rapid?

[stk2008]

hi again ummm I think its single start 5 pitch trapezoidel spindle.

but why does it only do it on that one axis

[stk2008]

hi again ive just swapped another motor off s different axis and tryed that it works good not one stall so ive checked me wireing thats ok to doh.

edit

ok ive got some weird problems going on here.

z axis at 100% rapid speed works perfect then if i change it to say 75% it starts then just stops making a noise but if i bump it back up to 80% rapid feed its as smooth a silk again?.

same goes for all the others axis not at 75% tho they are all different could it be vibration from motors?

me settings are motor tuning

steps per = 1600
velocity = 600
acc = 200
step pulse = 1 (as per instructions from diagram)
dir pulse = 5 ( as per instructions from diagram)

i do seem to have vibration at some speeds then at others its ok again?.

my psu motion control x2 42v 280w

drivers

motion control msd542

motors motion control fl86s (huge buggers)

i may try and change me kernal speed and allso change the power supply as its not that good
please advise on what i could do to fix this

cheers in advance.

[stk2008]

ok ive been doing yet more testing and im so convinced it vibration making the motors stop is this possible?.

as if i take the motor out of the cnc and place it on the bench it works perfectly but if i put it back in the machine i hear whats like a vibration noise just befor it stops.

im going to get some rubber washers and place them between the mount nd motor see if that helps but befor i do is vibration a possible cause or is the noise im heraing to do with the motor not working correctly any ways?.

[ger21]

Read the stepper motor damper thread. I made some dampers and my machine become perfectly smooth at all speeds.

[stk2008]

Read the stepper motor damper thread. I made some dampers and my machine become perfectly smooth at all speeds.

HI THANKS FOR REPLY YES I DID SEE YOUR THREAD BUT IS IT FULLY POSSIBLE TO HAVE VIBRATION STOP THE MOTORS?.

sorry about all caps just spotted it sorry.

[pminmo]

Sounds like your motors are resonating. You say your pitch is 5, and your steps per is 1600. If you haven't set your driver to a microstep size you need too. Can you post your actual screw pitch and your driver step size selection?

[stk2008]

hi again yes i would say they are its deffo some kind of vibration noise.

ok heres me kit

trapezoidel

http://www.worldofcnc.com/images/Tra...%20Spindle.pdf

its the tr20-4 im sure it is so the pitch is 4

ok heres me drivers btw my motors,psu,bob,drivers all came as a kit from motion control i have not touced the settings on the drivers they are set to

micro step/full step of 8 wich is 1600 micro steps per rev.

the amps set to 4.2amp.

cheers

edit

just for good measure heres me motors again

http://www.motioncontrolproducts.co....0(16%20mm).pdf

[pminmo]

If your screw isn't one revolution per unit, you need to include that figure into your steps per unit. i.e. if it take 2 revolutions to move one full unit, then steps per is 3200.

Assuming your metric and your units are mm, how many revolutions of the screw are necessary to move one mm?

[stk2008]

u are ahead of me i have not looked into that yet i have a dti so will check as soon as i can.

hehe im working in inch thats what we all use at work so thats what ive become use to so i will check asap what one revolution =.

so could this stall the motors at diff rapid speeds?.

[pminmo]

Since it figures into acceleration and velocity settings it will have an effect.

[stk2008]

ah ok then i will get onto setting that up asap and mainly me limit switches :O.

im working all week now tho and dont get a chance to after work as i have the kids only weekends so will check then .

thanks

[ger21]

If you have 4mm/turn, you need 6.35 turns/inch. 6.35*1600 = 10160 steps unit in Mach3.

If your in inches, for starters, set the accel at about 8 and velocity at 150.


First thing you do is go to Config>Select native units and set it to inches. Then close Mach3 and restart it. Then, go to the motor tuning and put in the nu,bers I gave you. Be sure to save each axis. Then, close Mach3 and restart. then you can start testing different velocities and accels

[stk2008]

hi again ive just managed to go out side for ten mins well ive now set it to 200 velocity and the speed to 400 seems good now i will go back out side when i can to set the steps per correct i will set it to what u say ger21 and cut a 1" square then see what i get cheers.

ummm i still think its to do with vibration tho as i could run em great at 500 but if i slowed it down to 75% jog speed then it stoped and made a nasty noise till i let go of key this was just the z axis the others where at diff jog speed that it stoped at.

[ger21]

It definitely sounds like you have resonance.

It also sounds like you have the native units set to mm.