Noisy/vibraty
December 27, 2008 05:16AM
Happy post-Christmas everyone,

My z-axis motor is extremely loud and it vibrates vigorously, but the problem isn't the motor since I've switched stepper boards, motors, tried another arduino, tried it without the breakout shield and the result is the same: whatever motor, board connected to these pins will have a noisy motor....

and the only common factor is (analog) pins 2,3,4,5 (Analog pins 2,3,4,5 are the same as Digital pins 16,17,18,19 respectively). Other common factors include the firmware that runs it (and plus I'm the operator grinning smiley). [dev.www.reprap.org]

What could be the problem? Anyone else having a noisy motor problem on those pins?

Arthur
Re: Noisy/vibraty
December 27, 2008 11:33AM
Arthur Wrote:
-------------------------------------------------------
> Happy post-Christmas everyone,
>
> My z-axis motor is extremely loud and it vibrates
> vigorously, but the problem isn't the motor since
> I've switched stepper boards, motors, tried
> another arduino, tried it without the breakout
> shield and the result is the same: whatever motor,
> board connected to these pins will have a noisy
> motor....


Arthur,

A few questions about what you're seeing/hearing:
Is your Z-axis motor rotating, or just vibrating in place?
Do you have other steppers (x, Y) behaving differently?
Do you have the jumper set for half (vs. full) stepping?
Have you adjusted the current (e.g. tried to turn it down somewhat?)

All stepper motors I've worked with "sing" as they're bing stepped, the faster they move, the higher pitch they emit. The noise is louder when you're driving the max current. Assuming the motor is rotating under load, you might try reducing the current until the motor drives the load (plus a bit of margin), but not a whole lot more.

You might use youtube to listen to smoe other peoples' stepper-driven machines in operation. That will give you a basis for comparison regarding the noise levels.
There are a wide variety of stepper-driven machines, in addition to reprap, that people have posted audio/video on youtube (and probably vimeo as well.) searching for CNC or stepper (in addition to reprap) should turn up a bunch. For the stepper-driven machine tools (mills, routers), note the sounds they make before they start cutting wood/metal/whatever; that way, you'll be listening to the steppers only -- not to the sound of the cutter blades on the workpiece.

Hope this helps,


Larry Pfeffer,

My blog about building repstrap Cerberus:
[repstrap-cerberus.blogspot.com]
Re: Noisy/vibraty
December 27, 2008 03:53PM
Hi Larry--

> Is your Z-axis motor rotating, or just vibrating
> in place?
// The loud noise/vibrations affect whatever motor is connected to those pins. The motor connected to Digial-pins-16,17,18,19 is rotating and working, though with lots of noise/vibrations and is slower than the other 2 motors.

> Do you have other steppers (x, Y) behaving
> differently?
// Yes, the other 2 motors are working fine. Noise seems appropriate.

> Do you have the jumper set for half (vs. full)
> stepping?
// all set to half stepping. All set to "master".

> Have you adjusted the current (e.g. tried to turn
> it down somewhat?)
// I've adjusted the current and there isn't a specific current where it just "works". You know how when everything is working right, there's this noisy period and then you add more current and then it goes smooth and sounds right? Well, for the one that's connected to Digial-pins-16,17,18,19, it does speed up a bit, but the noise doesn't really go away. When the motor/stepper-board combo is placed on pins occupied by X, Y, then it works great, so I know there isn't anything wrong with the motor/board per se.


Nice blog grinning smiley Looking forward to reading more about Cerberus.

Arthur



> You might use youtube to listen to smoe other
> peoples' stepper-driven machines in operation.
> That will give you a basis for comparison
> regarding the noise levels.
> There are a wide variety of stepper-driven
> machines, in addition to reprap, that people have
> posted audio/video on youtube (and probably vimeo
> as well.) searching for CNC or stepper (in
> addition to reprap) should turn up a bunch. For
> the stepper-driven machine tools (mills, routers),
> note the sounds they make before they start
> cutting wood/metal/whatever; that way, you'll be
> listening to the steppers only -- not to the sound
> of the cutter blades on the workpiece.
>
> Hope this helps,
Re: Noisy/vibraty
December 27, 2008 04:03PM
It may just be that the motor is more noisy because it is running slowly. If you change the preferences so that the z-axis motor moves at the same speed as the x and y does it get quieter?


[www.hydraraptor.blogspot.com]
Re: Noisy/vibraty
December 27, 2008 08:15PM
Arthur Wrote:
-------------------------------------------------------

> > Do you have other steppers (x, Y) behaving
> > differently?
> // Yes, the other 2 motors are working fine.

Well, for
> the one that's connected to
> Digial-pins-16,17,18,19, it does speed up a bit,
> but the noise doesn't really go away. When the
> motor/stepper-board combo is placed on pins
> occupied by X, Y, then it works great, so I know
> there isn't anything wrong with the motor/board
> per se.
>
>
> Nice blog grinning smiley Looking forward to reading more
> about Cerberus.

------

Arthur,

One thing you might try is to put one of the X or Y driver/stepper combos onto the pins that drive the Z axis. If that's noisy, then it suggests something is strange with those pins (voltages, currents, noise, etc.)

Thanks for your kind words re my (just started) build blog. (You may well be my first reader -- thanks!) I now have some photos of some parts/subassemblies for my repStrap; I'll try to put them up before the weekend's over.


Larry Pfeffer,

My blog about building repstrap Cerberus:
[repstrap-cerberus.blogspot.com]
Re: Noisy/vibraty
December 28, 2008 02:06AM
Yeah, thanks guys. I'll try nophead's suggestion. It makes sense since the noise/vibrations sound just like the noisy zone as you're slowly turning up the trimpot current on the stepper-board. Will need to look at the code -- my 2 college C/C++ classes should come in handy grinning smiley

In any case, I have full control of all the axis albeit with a noisy Z.

Arthur
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