y axis homing direction issues and endstop question

Hey again,

Anyone have a simple reason why when I home x,y,z the y goes the wrong direction ?? The motors are all hooked up in a similar fashion. I suppose I could wire it differently but it just seems odd. also, I installed (switch) endstops for the three axes. When I auto home, it hits the switch for each axis and stops..However, having hit the switch, I must move the axis by hand to open the switch again. Anyone have any ideas here ?? Thanks

You can either reverse the wire sequence so that 1234 becomes 4321 (180 degree) to reverse the motor in all axes or you can edit the firmware.

Thanks brnrd,
It's what I thought. It just seems odd to me. Any thoughts on the endstops ?

... which firmware is installed?

With my "FiveD_on_Arduino" i had X and Z inverted, but Y not

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Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

Arduino-21 for the extruder and Arduino-22 for configuration. Which way did you to solve the issue Viktor, changing the wires or the software ?? and if you changed the software, could you tell me where and what.

thanks

... i'm working with the Arduino-19 or -21 IDE's, as the -22 has some glitches.

My firmwares are the official Gen3-firmware (slightly modified) on the Gen3-electronics (i think it's the Sanguino-motherboard 1.3 and Extrudercontroller 2.2) and the "FiveD_on_Arduino" for my Arduino-Mega 1280 and 2560 with RAMPS.

You have to edit the settings in the firmware for inverting the specific directions ...

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Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

Rather than change the wires around I looked for and found this code in the configuration.h file and made the change to invert the y dir, noted in the last line. A simple change and things work fine. I'm just reluctant at this early stage to start hacking "known code" but oh well...it works!!


#define Y_STEPS_PER_MM 10.047
#define Y_STEPS_PER_INCH (Y_STEPS_PER_MM*INCHES_TO_MM) // *RO
#define INVERT_Y_DIR 1 // changed from 0 to 1 by BB 0509201

It is not "hacking" when you change define values that are there for the purpose of adapting the firmware to your hardware.
It is called "configuring"...

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Bob Morrison
Wörth am Rhein, Germany
"Luke, use the source!"
BLOG - PHOTOS - Thingiverse

Thanks Bob...and I agree. Now on to the current dilemma. As I mentioned above, for endstops, I used mechanical switches from makerbot

[store.makerbot.com]

and after configuring them to work with the RJ plugs they (appear to ) work fine. However, once the switch is made, it seems to disable the stepper motor board for that axis and I must manually move (the axis) to release the switch. Is this correct ? Does homing the unit rely on making contact with each of the endstops or are the endstops there as a precaution. If they are there as a precaution then do we "configure" the software somewhere for the proper homing location for our machine or if homing the unit does requires the endstops then how do we continue. Phew...so many questions..

thanks again

That's clearly not correct. When it trips the end-stop it should stop moving in that direction but should allow movement in the opposite direction.

A couple of things to try: use a mutli-meter to check the output voltage from the microswitch when it is open and when it is pressed - make sure it switches from VCC to GND as expected. Not sure about your hardware if it should be at VCC when normally open or if it should be at GND.

The other thing to check, in your firmware, make sure it doesn't expect multiple end-stops. One at home and one at the extreme. Some electronics determine a missing end-stop as a 'hit' end-stop. So it could be when you home the axis the missing end-stop prevents the axis from moving in the other direction because it thinks it is tripped too. Look for:

#define ENDSTOPS_MAX_ENABLED 1

somewhere in configuration.h, set it to 0 if you find it (and you only have home end-stops, of course).

Regards,

James

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Check out my blog: AdventuresIn3-DPrinting

If the steppers are able to move in both directions, then your endstops are probably wired correctly. If not, they will only move in one direction since the microcontroller thinks that you are already at the endstop. The direction that it moves, in this case, is the positive direction.

I change my wires to be consistent with the default for the firmware so that I don't have to change it everytime I change versions.