x axis problem? not homing proper acting right

[Arctic Artist]

I have had my machine since the end of Feb. The build went fairly easy and was up and printing with decent results within 3 days except for printing larger objects due to software stall or having to re calibrate bed and axis height. I had noticed the black dust in tower wells but thought it was a sign of machine breaking in. So I then proceeded to build the lcd adapter and install for unattended printing but to no avail my lcd just displays boxes and gives a LCD fail remark in Repeiter software. So I reinstalled the new windows installer but same LCD error. I then proceeded to give up on the LCD for a project I needed to produce but now my x axis homing or otherwise will not stop moving..? even after hitting limit switch it slows to shot step increments and proceeds to eat my belt? I switched out the motors on the rambo but they all are skittery on the x axis. is my card messed up? or is there a software adjustment I can try? I have a CNC machine and am experience with gcode but the belt fed 3d printer thing is very new to me. any advice would be great.

[Flateric]

I had the very same issue after I had fiddled around with my rambo and moving it around.

In the end I found that my stepper motor plugs or rather the pins going into the plug had pushed out and were not fully connecting.

And the second time (yes happened twice but different reason sort of) the pins had not the best crimping (gee wonder who did that poor job ...ok it was me, lol) and were making intermittent connections.

[Polygonhell]

Have you verified the limit switches are working as described in the manual?
M119 to check the state, verify it changes when each switch is pressed etc.

[Arctic Artist]

Thanks for the advice, I will double check connections but I did switch motors to each different axis on board and got same jitter on all of them coming from x axis port on card.. and yes I did initialise the switches prior to this and when loading new firm ware so im still puzzled and hoping board is not damaged..Im not sure how it could have happened though it started when i tried to install the LCD adapter.. grrr

[cassetti]

Maybe a loose connection on the limit switch?

[Eaglezsoar]

Perhaps the digipot value for the X axis is not set correctly?

[Arctic Artist]

After double checking all connections and even setting lower digipot settings in firm ware nothing has changed, also replaced the mechanical end stop and switched out motors but same results ..which is entering G28 to home ..all motors travel to top and press end stops, back off programmed distance tap end stops again and stop..all except x axis which maintains pressure against end stop until it starts popping or rather skipping teeth on belt chewing it up. vice versa in opposite travel say g1 z200 f1200 it will go to programed position but x axis continues to travel in same slight step increments whilst other axis's have stopped. John Olly advised me to send my board back but just wanted to post this in case someone else had a ghost in their machine as well..
Im pretty convinced its my rambo but am sad that my machine will be down for a while.
- Thanx for everyones input here!

[Polygonhell]

I'm going to ask this question again.

Have you verified the limit switches are working as described in the manual?
M119 to check the state, verify it changes when each switch is pressed etc.

If they report correctly, it's most likely not a RAMBO issue.

[Arctic Artist]

Polygon, Yes the switches are all reporting H value in repeiter when pressed but x axis after it reaches top of tower trips limit then raises back up under force continuing to step motor ...I have switched the axis motors from all to x port on card and all do the same thing isolating the issue to the x axis on Rambo or some issue in software for this axis. I uninstalled all software did clean install, flashed new firmware even played with digipot setting to what you are setting at and still same issue occurs. In last ditch effort before sending my Rambo back to john I am re wiring everything from scratch to see if there is a snag somewhere. This all started when I installed new adapter for my LCD(which did not work only came up with squares) The board looks fine, like brand new no visible damage.. Very frustrating. I live in Alaska and not much support here so Im trying everything before sending my card back. You say though that if its recognizing end stops then its probably not the board? then why does this occur with all motors? and from only that axis on the card?I am fairly good at troubleshooting but has me perplexed. could I be overlooking something else?

[Polygonhell]

the switches are all reporting H value in repeiter when pressed but x axis after it reaches top of tower trips limit then raises back up under force continuing to step motor

I assume they all report L when not pressed.
Then it's unlikely to be the RAMBO board (or at least the endstop part of it), M119 is reading the same thing that the firmware is reading to home.

There are a number of things it could be - bad stepper wiring/firmware configuration/bad dir pin not being set by RAMBO board

Has the XAxis ever moved down under motor control?
If you swap the X and Z motors on the board does the problem move to the Z axis or stay on the X?

What firmware are you using?

[Arctic Artist]

Yes the axis all read L when not pressed and all motors move down when commanded but x axis will continue moving in small incremental micro steps on its own. I have switched all motors to the x port on card and they all do same thing. I have owned this since Feb and never had issues other than working out print quality with our very cold ambient temperature here so I would have to print at higher temps and bed temps or no adheision between layers would work. I dont think that has any thing to do with this issue but just suggesting I have had the printer running for a while with no issue until I went to install my LCD after I could not get it to properly display I removed and this problem reared its head..could this be pin problem? I reinstalled the new Arduino 1.03 and rostaller windows version of marlin 1.1a and new version of Repieter v0.85b does this help?

[Polygonhell]

but x axis will continue moving in small incremental micro steps on its own.

This is usually a sign of bad wiring on the stepper.
but

I have switched all motors to the x port on card and they all do same thing.

Then unfortunately I think you are probably right it's likely a blown driver on the RAMBO board.
You could swap X and extruder2 in pins.h if you wanted to get running.

[Arctic Artist]

Polygon you are a god amongst men -Good idea, I will try that and that would narrow it down completely I think.. then there should be no question.. Thank you again you're pretty smart I was out of ideas..I will let you know what happens

[Arctic Artist]

Polygon can you give me brief run down on how to switch these values in pins.h I am going to go tinker but having a mentor would be most helpful?

[Polygonhell]

Depends on the firmware, but basically you find the section for the RAMBO board it will be inside a section that looks like this
#if motherboard == 301

Then you need to swap the pin definitions for the Step, Dir and Enable pins
for example if it's
#define X_STEP_PIN 37
and later in that section
#define E1_STEP_PIN 33

then you swap the 37 and 33 over and do the same thing for dir and enable

[Arctic Artist]

but what about e_min and e_max values?

[Polygonhell]

but what about e_min and e_max values?

You just need to swap over the pins that control the stepper step, dir and enable
No need to touch anything else.

[Arctic Artist]

OK so weird... Polygon I believe you were right about it not being the Rambo. I uninstalled everything and down loaded the new REPIETER firmware from seemcnc download page and uploaded it with 15 tooth pulley and basic info and everything works including my LCD only problem now is the carriage wont go all the way down to my bed. It stops short about 175mm and wont go down any further Im confused and tired now. I wil try again tomorrow but, I just wanted to thank you and everyone else who was trying to help...bad firmware glitch im guessing? but if anyone knows an answer to this bed height thing?

[cambo3d]

OK so weird... Polygon I believe you were right about it not being the Rambo. I uninstalled everything and down loaded the new REPIETER firmware from seemcnc download page and uploaded it with 15 tooth pulley and basic info and everything works including my LCD only problem now is the carriage wont go all the way down to my bed. It stops short about 175mm and wont go down any further Im confused and tired now. I wil try again tomorrow but, I just wanted to thank you and everyone else who was trying to help...bad firmware glitch im guessing? but if anyone knows an answer to this bed height thing?

have you checked your eeprom xyz max heights? also check you have your steps per mm set properly also,

[dbarrans]

Change microsteps from 16 to 8 in the firmware if you have a 1.0 RAMBo.

- dan

[Arctic Artist]

Thanks but I have the newer RAMBO so already at 16 steps and firmware is set right as well as printer set up in Repeiter. what else could it be? the carriage stops 100mm above bed at z0...

[Arctic Artist]

Ok so I entered z value in eprom to 493.80 to get z axis to be @0 ..re-leveled bed and it is now printing.. better than ever..not sure why and i dont care...its printing yea.. i will update later... thanx all.

[dsnettleton]

I had the very same issue after I had fiddled around with my rambo and moving it around.

In the end I found that my stepper motor plugs or rather the pins going into the plug had pushed out and were not fully connecting.

And the second time (yes happened twice but different reason sort of) the pins had not the best crimping (gee wonder who did that poor job ...ok it was me, lol) and were making intermittent connections.

Incidentally, though Arctic Artist had an apparent firware problem, you really helped me out here, Flateric. I've been getting some spotty prints for a while now, and had determined it wasn't the firware, a mechanical problem (delta arms), or the slicing/GCode. I wasn't sure what else it could be. But I read your post and gave my wires a jiggle to test how secure they were. I did this in the middle of a print, causing the hot end to drop into the knob I was printing. Yep. That's the problem. I knew I should have bough some crimpers instead of using those needle-nose pliers. Oh well. I've fixed the wiring and I'm making another attempt at that knob. I should know right away just from the infill on the bottom layer...

[ROBRMI]

I had a similar problem on my X axis motor homing. When i de-constructed, and re-made the connectors i found that the pin on the blue wire was "split" and not making good connection all the time. so even if the wiring looks good be sure to inspect the pins themselves. I actually wish they had a small screw terminal header for the motor and other connections on the Rambo board. I've always hated crimped pin connections.