SOLVED:Z Axis issues

Hi All,

Thanks for all the input guys, ended up solving it by mashing up nobheads and the original marlin together all is good now have done some test prints and all looks good.

Cheers, Stubbienz

Have just finished building my mendel 90 and am running into a few issues, with the Z axis and homing at the top.
x and Y are not a problem they home at the stops not a problem.

On Z when it homes on the endstop at the top does the axis then change its position to 203 or is it meant to stay at 0.0 as I thought the 0.0 was meant to be when it is down by the glass.

AT the moment where ever the head is when I turn it on up the x axis it takes this as 0.0 and wont go down past here but when I go up it will stop at the endstop at what ever the distance it has gone up by one this happens it will go back down to 0.0 which it where it was at when switched on.

Attached is a link to the marlin im using

[www.dropbox.com]

This was nopheads original but I am running it on a arduino board with the ramps 1.4 controller.

Any help most appreciated thanks for your time.

One other thing I have a 3dgadget controller is there an easy way to integrate the files from the new marlin to nopheads so the info will be displayed?

Cheers Stubbienz

Edited 1 time(s). Last edit at 12/29/2012 03:53PM by stubbienz.

You talk about "close to the glass"; are you sure you aren't talking about the Z axis. The vertically up/down one is the Z axis, the Y axis is the moving bed, and the X axis is the moving extruder sliding along its rails left and right.

Gerv

Whoops sorry it was late when I posted, have updated with the correct info. Thanks

Yes when it starts it assumes 0 and will only go up. When it hits the endstop it should set it to 203 and then be able to go down as far as the glass. The switch needs to be connected to the MAX pin. It sounds like you are using the MIN endstop pin. On the boards I use there is only one pin but on RAMPS there are two,

I think my mods to allow the limit at the top have been incorporated in the main line branch of Marlin some time ago. I never update software unless I have to because inevitably it gets bigger and more buggy.

Edited 1 time(s). Last edit at 12/29/2012 06:39PM by nophead.

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[www.hydraraptor.blogspot.com]

Getting closer, when i hit the home button now it splutters then sets the home to 203.0 if I move the head up through steppng when it reachs the top and hits the end stop it resets to 203. what would need to be changed to allow when hitting home for the head to travel to the top too set it at 203 instead of spluttering and seting it self before getting to the top?

Cheers, Stubbienz

Seems like you have cross talk between the motor wires and the endstop wires. Have you twisted them and run them separately with the double holes and double cable clips?

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[www.hydraraptor.blogspot.com]

Gidday,

No all good, was more me being a muppet when it comes to marlin than anything else, starting from scratch with the code was easier for me than trying to get the other to work. Did a few prints last night and very impressed

Great Success

Thanks for all your help.

Cheers, Stubbienz

Edited 1 time(s). Last edit at 12/30/2012 02:23PM by stubbienz.

One more quick question,

When conducting the home sequence, should the steppers not 'bounce' off the switches after it is homed?

Thanks,
Chris

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Custom all metal CoreXY
- Duet 2 Wifi w/ PanelDue 7i
- 330mm x 360mm x 500mm
- 750w Silicon heater

Custom Mendel90
(Backup printer - Old reliable!) - Sold

yip clicks one forward on the xy but not on the Z

It should hit, back off, hit again slower and back off 1mm on X & Y, less on Z.

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[www.hydraraptor.blogspot.com]

nophead Wrote:
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> It should hit, back off, hit again slower and back
> off 1mm on X & Y, less on Z.


Thanks, that's what I thought, it's not doing that... just hits the switch and stops....
Is that in your revision of Marlin, or is that feature/function in all Marlin versions now?

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--------------------------------------------------------
Custom all metal CoreXY
- Duet 2 Wifi w/ PanelDue 7i
- 330mm x 360mm x 500mm
- 750w Silicon heater

Custom Mendel90
(Backup printer - Old reliable!) - Sold

My fork does it but I didn't change anything code wise. It is just what Marlin did at the time. I haven't tried any more recent versions.

It might just be a configuration option. Certainly the reason it backs off the second time is because I defined the home position is 1mm away from the min pos on X & Y and 0.1mm on Z.

// ENDSTOP SETTINGS:
// Sets direction of endstops when homing; 1=MAX, -1=MIN
#define X_HOME_DIR -1
#define Y_HOME_DIR -1
#define Z_HOME_DIR  1

#define min_software_endstops true //If true, axis won't move to coordinates less than HOME_POS.
#define max_software_endstops true  //If true, axis won't move to coordinates greater than the defined lengths below.
// Travel limits after homing
#define X_MIN_POS -100
#define X_MAX_POS 100
#define Y_MIN_POS -100
#define Y_MAX_POS 100
#define Z_MIN_POS 0
#define Z_MAX_POS (Z_HOME_POS - 0.1)

// The position of the homing switches. Use MAX_LENGTH * -0.5 if the center should be 0, 0, 0
#define X_HOME_POS (X_MIN_POS - 1)  
#define Y_HOME_POS (Y_MIN_POS - 1)
#define Z_HOME_POS (203.0)

#define X_MAX_LENGTH (X_MAX_POS - X_MIN_POS)
#define Y_MAX_LENGTH (Y_MAX_POS - Y_MIN_POS)
#define Z_MAX_LENGTH (Z_MAX_POS - Z_MIN_POS)

The amount it backs off the first time is in Configuration_adv.h.

//homing hits the endstop, then retracts by this distance, before it tries to slowly bump again:
#define X_HOME_RETRACT_MM 2 
#define Y_HOME_RETRACT_MM 2 
#define Z_HOME_RETRACT_MM 1 
#define QUICK_HOME  //if this is defined, if both x and y are to be homed, a diagonal move will be performed initially.

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[www.hydraraptor.blogspot.com]

Hi Nophead,
Sorry for being a pain, I'm not getting the bounce off the limit switches.
The retracts are there as you described, but not happening?
Other then the bounce, the setup is now working correctly.

const bool X_ENDSTOPS_INVERTING = false;
Now if I change this to true, the axis goes in the opposite direction (away from the limit switch)
and if I manual hit the switch during the home sequence, the bounce happens.

I'll take a video of whats happening if I'm not describing this well enough.

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--------------------------------------------------------
Custom all metal CoreXY
- Duet 2 Wifi w/ PanelDue 7i
- 330mm x 360mm x 500mm
- 750w Silicon heater

Custom Mendel90
(Backup printer - Old reliable!) - Sold

X_ENDSTOPS_INVERTING should be false for a switch wired NC to ground as the signal goes high when it is pressed.

Changing it should not change the homing direction although it might think it is already at the end stop so back away to start with.

I have no idea what the latest Marlin does. It is in a constant state of flux so I had to take a snapshot and work with that as I can't support kits with software that changes daily.

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[www.hydraraptor.blogspot.com]