Mini kossel homing issue - motors skipping and shaking

Hi! First I wanna say that I'm completely new to 3d printing and everything related to it, especially the programs and coding. Also, I'm not an english native speaker, so be kind

Here's my problem: when I try to home the carriages, they basically go completely nuts. They do go up, but they are shaking and skipping steps making a horrible noise. I got my kit from here and it didn't come with the usual stepper wire colours blue red green and black, but with red green grey and yellow. Also, the carriages come really close to the endstops and then start to shake really hard as if they can't make it any further. Yesterday I've noticed that they work perfectly fine when I wire them the wrong way, so that they go down when homing. I tried lowering the homing feedrate and acceleration in configuration.h, but it didn't work. I also tried tightening the belts; didn't work either. Btw. I'm using 12V to power it
Anyone have any ideas? Thanks in advance

If you are using RAMPS electronics, check that you have the jumpers under the driver modules set for 16x microstepping.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Quote
dc42
If you are using RAMPS electronics, check that you have the jumpers under the driver modules set for 16x microstepping.

I'm very sorry to bother you, but I don't know how to do that Could you give me some instructions please?
Edit: figured it out; under the driver modules of every motor there are jumpers on ms1,ms2 and ms3, so I guess they are set for 16x stepping?

Edited 1 time(s). Last edit at 10/04/2015 04:08AM by Lul1811.

It sounds like your carriers hit the endstops, but the motors don´t stop...
This could be related to wrong wiring position on the Ramps board. #see attached picture

The front left endstop should be wired to x-Max pins ( second column from left )
The front right endstop should be wired to y-Max pins ( fourth column from left )
The rear endstop should be wired to z-Max pins ( last column )

If that´s OK, you can also check the switching logic with sending M119 trough pronterface.
All endstops should read "open" when NOT homed, and the MAX-endstops read "triggered" when ( manually ) homed.

Edited 1 time(s). Last edit at 10/04/2015 04:41AM by o_lampe.

Quote
o_lampe
It sounds like your carriers hit the endstops, but the motors don´t stop...
This could be related to wrong wiring position on the Ramps board. #see attached picture

The front left endstop should be wired to x-Max pins ( second column from left )
The front right endstop should be wired to y-Max pins ( fourth column from left )
The rear endstop should be wired to z-Max pins ( last column )

If that´s OK, you can also check the switching logic with sending M119 trough pronterface.
All endstops should read "open" when NOT homed, and the MAX-endstops read "triggered" when ( manually ) homed.

They don't hit the endstops, just get really close to them. I checked the wiring and everything is fine. Sent M119 and it reads open when not homed (except z-min which is triggered) , but there's a problem when i manually home: if i home before connecting to proterface it won't connect and sends this message:
Connecting...
[ERROR] Could not connect to COM3 at baudrate 250000:
Serial error: could not open port COM3: [Error 2] The system cannot find the file specified.

If i connect and then home, it sends:
[ERROR] Can't write to printer (disconnected?) (SerialException): Write timeout
Disconnecting after 4 failed writes.
Disconnected.
and disconnects the printer

Edit: tried homing again, as soon as one carriage hits the endstop, they all start shaking and skipping.

Edited 2 time(s). Last edit at 10/04/2015 04:55AM by Lul1811.

You might have a shortcut in the endstops or wired them the wrong way? So,the controller shuts down, when an endstop is triggered...

Quote
o_lampe
You might have a shortcut in the endstops or wired them the wrong way? So,the controller shuts down, when an endstop is triggered...

I checked everything and all seems to be wired correctly. I tried putting the pins from the endstops the other way - still not working. The wires on the endstops end are wired from top to bottom: red, black, skip ground, green

Use M119 to verify they working correctly.

Issue a M119 to see what is reported back, then manually press and hold one of the endstops while issuing a M119.

Do this for all 3 endstops.

Quote
Lul1811

Quote
dc42
If you are using RAMPS electronics, check that you have the jumpers under the driver modules set for 16x microstepping.

I'm very sorry to bother you, but I don't know how to do that Could you give me some instructions please?
Edit: figured it out; under the driver modules of every motor there are jumpers on ms1,ms2 and ms3, so I guess they are set for 16x stepping?

If you have A4988 or A4982 based drivers, there should be jumpers across all 3 pairs of pins under each driver, as here:



EDIT: OK you checked already, so it is a different problem.

Edited 1 time(s). Last edit at 10/04/2015 06:13AM by dc42.

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

throwing my 2cent in here.

Is the baudrate in the firmware 250000?

Then you connect to pronterface and type in M119 all endstop read open?
Manual press each endstop with your finger and send m119 and see if each reports back as triggered and for the right tower (i.e. Z max for the z motor, x or x etc..)
Also make sure all the wires are in the plug good.
A member had one 1 come out of the connector and cause the carriage to move slowly and shake like it was about to fall apart.

Quote
Lul1811
Yesterday I've noticed that they work perfectly fine when I wire them the wrong way, so that they go down when homing.

I would wire them the 'wrong way', and then reverse the direction in the firmware. In configuration.h I would change the following:
INVERT_X_DIR
INVERT_Y_DIR
INVERT_Z_DIR


Also have you set the current of your steppers, using a screwdriver and a multimeter?

Quote
nebbian

Quote
Lul1811
Yesterday I've noticed that they work perfectly fine when I wire them the wrong way, so that they go down when homing.

I would wire them the 'wrong way', and then reverse the direction in the firmware. In configuration.h I would change the following:
INVERT_X_DIR
INVERT_Y_DIR
INVERT_Z_DIR


Also have you set the current of your steppers, using a screwdriver and a multimeter?

I did it, and its still the same. When they hit the endstops, they back up a little and start shaking.
I didn't check the current, i don't have a multimeter...trying to rule everything else out before i buy one

Edited 1 time(s). Last edit at 10/04/2015 11:28AM by Lul1811.

Quote
xile6
throwing my 2cent in here.

Is the baudrate in the firmware 250000?

Then you connect to pronterface and type in M119 all endstop read open?
Manual press each endstop with your finger and send m119 and see if each reports back as triggered and for the right tower (i.e. Z max for the z motor, x or x etc..)
Also make sure all the wires are in the plug good.
A member had one 1 come out of the connector and cause the carriage to move slowly and shake like it was about to fall apart.

Everything works fine, and they are all wired correctly. And yes, the baudrate is 250000

Quote

When they hit the endstops, they back up a little and start shaking.

Now that's a different story! The endstops seem to work, because the backup indicates it.
Try to reduce the homing speed, I´ve seen versions of marlin where homing was set to 200x60mm/min. I reduced it to 60x60 and it works fine.
-Olaf