So in the middle of my x (or y) travel I suddenly get the dredded HUMMMM while rapiding to a known good location, I am not at the end, if I stop and restart the rapid it goes for a few more revolutions then hums again, (I know i am in the center of my usable area so that is not it) the gibs do not seem too tight, I can if I take the stepper off, hand rotate through the entire range with no apparent effect, what could be the issue guys?

Bryan

Could be several things: motors not tuned properly, motors not installed properly (binding), poor output waveform from parallel port, bad stepper motor, bad driver...

Give us a better idea of your setup. What types of steppers, what driver, what are your motor tuning settings. Then I bet someone can give you some good pointers.

Jeff...He has the Older Deepgroove Driver..

Try setting your Rapid to 10 ipm...might help....Keep in mind too loose on the gibs can bind also under rapid.....

Bring your acceleration Slider over to the right more so that you have a Flat line....You don't want a Pointy curve....Make sure you do this with all axis's and Save....Should Help

It is a deep |groove 1 controller box
280oz stepper motors
Running mach 3 as software
Rapid set to 12 IMP (300mm/min)
my acceleration curve has a ramp up, then a flat top, then a ramp down

I have gibs just lightly-snug (hard to explain) but no loosness but not too tight.
I will get rid of ramping in Acceleration curve and slow it down to 10 ipm (254mm/min)
Motors well they seemed to work before, I hope nothing has happened to them in the short time I have owned them.

Jeff u sell the gekko 540 right, how hard is it to change over from the deep groove to the Gekko?

What would the big changes be that I would notice when using it compared to the Deep Groove?

DO you want to buy a deep groove so you can compare.... (I could swap ya ),
( ok I had to try that last one)....

Bryan

Bryan...you will have a Ramp up ...just try to get the Flat Portion as long as Possible at around 10 ipm......

Mine Worked fine like this when I had that Controller....Just Kinda Slow

Hurray Yes it does work at 10 ipm (254mm/min), and the hum is gone, yes there is a little ramp at start and end but essentially flat, thanks for the help, you know its help like this that would lead to long frustrating hours sitting in front of your machining center if it were not for guys like you and Jeff and the others who are so helpful here!

PS the results are on the Cut 2D and Cut-3D page.
http://taigownersclub.forumotion.net/taig-cnc-mill-f1/vectric-products-software-cut-3d-etc-t319.htm

Bryan

Glad it worked out for you....Thats why I originally said 10-12 ipm....some are able to get away with 12 but most 10 seems like the sweet spot for those Drivers

You May or May not get the humm every once in awhile there.....If you do go to 9 and see if that Helps

Just have to Find out whats best for your Setup......

Looks like you are Having Fun with it anyway and thats the Main thing.....