BeagleBone with Cramps X stepper vibrates but does not move

[John Hammond]

The Y and Z steppers rotate but the X one does not. I have switched the Polulu driver from the X to Z and it works fine. Where is the pulse rate determined in Linux? Does Machinekit have linuxcnc files that I haven’t seen?

[John Hammond]

When the stepper is plugged into the Y-axis or Z-axis Polulu it rotates, when pluggedinto the X-axis Polulu, it just vibrates. The stepper is not driving anything. What needs to be changed in software to repair this?

[ce...@tuta.io]

Hi,

Mar 13, 2020, 20:17 by hammon...@gmail.com:

> When the stepper is plugged into the Y-axis or Z-axis Polulu it rotates, when pluggedinto the X-axis Polulu, it just vibrates. The stepper is not driving anything. What needs to be changed in software to repair this?
>

Frankly, I have no idea. But I take it that you tried the problematic driver in other socket? And there it was working? How many drives do you need, CRAMPS has 6 sockets, so can you live with (six-one not working)?

I think what needs to be determined is if the problem with socket/driver is hardware one or software one. (It could be that the BBB pin is dead.)

Cern.

>
> --
> website: http://www.machinekit.io blog: http://blog.machinekit.io github: https://github.com/machinekit
> ---
> You received this message because you are subscribed to the Google Groups "Machinekit" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to machinekit+...@googlegroups.com.
> To view this discussion on the web visit https://groups.google.com/d/msgid/machinekit/6df717cf-2d7b-430a-ac12-b525f1dac1ca%40googlegroups.com.
>

[Charles Steinkuehler]

Typically the pulse rates will be determined by settings in your HAL
file. Using the BBB, it is quite easy to generate rates so high you
overwhelm the stepper driver and get no actual movement from the
steppers. Often, this is an issue with the scale values, but there can
be other causes as well. Provide your HAL and INI config files, and we
can review.

--
Charles Steinkuehler
cha...@steinkuehler.net

[Tom M]

Are the steppers the same between the x and the z?

Have you adjusted the pots on the drivers?

Are they the same drivers?

Are you sure you have the cables wired correctly?

Is voltage, motors etc... Spec'd to the load?

I don't know your skill level. I hope this does't come across as Captain obvious.
(When i built my MPCNC I used a 5/16-18 threaded rod as the lead screw that caused me nothing but pain. I get these frustrations)

What kind of Cnc are you making?

[John Hammond]

I noticed that one of the connectors had slipped back a little in its housing. When I pressed it in and increased the voltage to the stepper from 12 to 24 volts, it started working. When I hooked up all three steppers in place in the CNC, the fuse in the power supply blew. I will work on a better power supply which eliminates spikes. Perhaps it was a spike that bricked the last two BeagleBone Blacks. Thanks all for your help.

[John Hammond]

I have a DIY CNC. It was powered before with LinuxCNC on an old laptop. The laptop became unreliable soI have been attempting to get it to work with Machinekit on a BeagleBone Black with Cramps board.

[John Hammond]

Hello Charles,

Attached are the hal and ini files that I believe are being used. Now all of the steppers are working. The CNC is moving. The X and Z are moving in the wrong direction. I suppose there is some documentation that shows me what to do next. I need to adjust the scale, I think. Sorry that it took me so long to remember how to copy the files to the SD card so I could send them.

[John Hammond]

Not sure how to capture Axis program startup log. Sometimes when I hold down continuous button in Axis for X-Axis it translates less than one inch and sometimes it will translate 10 inches without pausing. What values for velocity and acceleration should I start with to eliminate pausing? Is the machine not entering real time?