Printing Issues

I'm having a horrible time trying to get my Ormerod to print correctly.

I've put the Z Probe Homing and Bed Plane Compensation in the config.g file. (Screenshot.)

Then I run a G32 command after starting Pronterface to set the compensation.

I then home all axes and set the Heater to 205 and Bed to 65 (I'm using PLA.)

After waiting a few minutes for them to stabalise at those temperatures I send ormaxis.g to print. This is where the problem arises.

It either prints nothing (crashes the head so it can't extrude) or looks to print correctly, then promptly begins to drag the cooling string of plastic around, forming what I would describe as a tangled mess.

I really have no idea what is the best way to set it so that this doesn't happen! Any suggestions?

(Also on a non-related issue, sometimes when trying to print, I recieve the error 'Not SD Printing' in Pronterface.)

Happy New Year to everyone, I'm popping out to a party now, so I will read your replys in the New Year!

Thanks in advance,
Josh (Red RS Ormerod #323)

1. I think you need to home all the axes before doing the bed plane compensation. This is my setbed.g file:

; RepRap Ormerod bed setting procedure
G1 Z2 ; raise 2mm
G28 X0 Y0 ; home the X and Y axes
G1 X60 Y0 ; move to nearest corner foil
G28 Z0 ; home the Z axis
G32 ; execute bed plane measurement procedure
G1 Y190 ; get the head out of the way so we can clean the bed

I have the appropriate G31 and M557 commands in config.g. I'm going to add a command in setbed.g to turn on the bed heater at the start, then wait for the temperature to stabilise before executing the Z home and G32, because I've heard that the bed temperature can affect the bed height.

2. If it's crashing the head then it sounds like you have a z axis calibration problem. The Z sensor board as supplied is extremely sensitive to sunlight and to bright incandescent light (I've changed some component values on mine to make it less sensitive, and swapped a halogen ceiling bulb for an LED one). So you need to determine the correct G31 command with little sunlight or incandescent light, and run setbed.g under the same conditions.

3. Clean the Kapton bed surface with isopropanol or acetone before you start to print.

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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].

Hey Josh,

Had my first print-attempt (Ormaxis) yesterday and had a somewhat similar problem.
The bed compensation and homing seems right, but after a while the print gets dragged around by the print head.

Have you solved your issue, and can you tell me what you did plus your temperature settings?

Thanks in advance!

Henrik

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RS Ormerod No 080

I always home the Z axis by hand immediately before any print job as I have not found the present automatic method to be reliable.
The bed compensation (G30) commands are in my config file so they are already loaded at the start, as is the axis compensation.

1) Home X and Y
2) Get the bed up to temperature and clear any plastic that may be hanging from the nozzle.
3) Ensure the nozzle is above bed height then move to the position you used for your first bed compensation point (i.e. the position at G30 P0). For me that's G1 X30 Y60
4) Put a sheet of paper under the nozzle and slowly lower it until the paper is just catching under the nozzle. You should be able to move the paper but feel it dragging - you can feel the vibration of the steppers through the paper as you slide it around.
5) Send the command G92 Z0 to zero the Z axis.
6) Check the reported position (M114) just to be sure the Duet knows it's at X30 Y60 Z0
7) Start the print

If the head still drags or is too high (perhaps only on part of the print), re-do your bed compensation (it means that the bed has shifted significantly, which I have found it is prone to do)

Edited 1 time(s). Last edit at 01/08/2014 08:13AM by dmould.

Quote
dmould
5) Send the command G32 Z0 to zero the Z axis.

Did you mean G92 Z0 ?

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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

Quote
dmould
5) Send the command G32 Z0 to zero the Z axis.

Did you mean G92 Z0 ?

Yes - I've edited my post to correct that mistake - thanks for pointing it out.