Page 1 of 1

How to calibrate the print size?

Posted: Mon Jan 21, 2019 10:17 pm
by onki
Hi,

I have printed a disc with a original diameter of 125mm. The real part just has 122mm.
Is there any calibration possible in the firmware?

Is it better to change the stepper parameter in the firmware which means a recompile & transfer or should I try to scale the object using the slicer?

Best regards
Onki

Re: How to calibrate the print size?

Posted: Tue Jan 22, 2019 2:17 am
by _kaktus_
Hi.
:mrgreen:

In the first step I propose to calibrate all drives.
In the second step, if necessary, I suggest making corrections to the model.

Depending on the type of material (filament) the shrinkage can be different.

Re: How to calibrate the print size?

Posted: Tue Jan 22, 2019 4:43 pm
by onki
Hi,

Thnaks for your suggestion.
I have downloaded the i3A firmware files but I can't find where to calibrate the axes.
The configuration.h is more related to board types etc.
Is there a function in the frontend to set the steps /cm without flashing (and configuring) a new firmware?

Best regards
Onki

Re: How to calibrate the print size?

Posted: Fri Jan 25, 2019 6:22 pm
by onki
Hi,

I have found this line in the firmware source code:

Code: Select all

#define DEFAULT_AXIS_STEPS_PER_UNIT   {78.74, 78.74, 2560, 95}
Are these the default values for the i3 Aluminum?
If so I should be able to set them to higher values for X and Y using G code command:

Code: Select all

M92 X80.71 Y80.71 Z2560
Is that correct?

Can this M92 be used to read out the currently set values?

Best regards
Onki

Re: How to calibrate the print size?

Posted: Tue Feb 05, 2019 6:53 pm
by onki
Hi,

I managed to calibrate my I3 Aluminium without touching the source code.
First I checked the current setting for X/Y axis using GCode M503.

Since the printout was about 2,5% too small I have multiplied the current factors (78.74) to get the corrected value of 80.71.

The new value was sent to the printer using M92 command. I finally saved the new values to the EEPROM using M500 command.

Now the print size is OK.

Best regards
Onki