BI V2.5 Calibration notes

BI V2.5 Calibration.txt

Stepper Calibration (Current)
=============================
Check the Vref of your steppers first, They should be at around 450mV for the X,Y,Z axis. And 700mV for the extruders.

You need a multimeter, a small screwdriver, a steady hand and a lot of patience. With the BI on its side, power it up.  Look at each of the drivers (that would be a row of 4-6 identical daughter boards on the RUMBA board. There is a small (really small) potentiometer, that's the screw.  Look for the point labeled GND.  Take the ground lead from the multimeter and touch it to the GND point, then put the hot lead of your multimeter on the screw -- that will give you the current voltage.  

For safety's sake, turn off the printer before adjusting the pot.  Use a small screwdriver to adjust the pot. A tiny movement may make a big difference in the voltage so go slowly. Check the voltage. Adjust. Check again. Adjust....


Bed Levelling
=============
First use digital calipers to adjust bed levelling bolts so that they are all evenly spaced from the top of the aluminium to the metal base of the printer.
     
        Adjust Bolt so that
______/--\___  _____
             |       Distince between here
    Bed      |       
_____________|    
       ||           
       ||            
----------------------------------- and here is the same for all 3 sides of bed


Enter the following gcode, one line at a time, with bed and extruder heated, measuring and adjusting the bed height to be 0.1mm from the hotend when it is fully deployed. I highly suggest using feeler guage instead of paper to measure the height.

G28 
G1 F8000 X-77.94 Y-45 Z0
G28
G1 F8000 X77.94 Y-45 Z0
G28
G1 F8000 X0 Y90 Z0
G28
G1 F8000 X0 Y0 Z0

For me:
Z Max length:     401.400
Extr. 1 Y-offset: -900



Extruder Steps/mm
=================
measured when feeding filament but not pushing through hot end.

current firmware steps/mm * 100 / actual extruded length
=188.011917147

Set the steps per mm in your eeprom settings for the extruder you are configuring.
if this makes no sense to you watch https://www.youtube.com/watch?v=YUPfBJz3I6Y


Horizontal Radius
=================
If you compare the outside diameter height to the center height you'll either have to increase Horizontal Radius if the center is higher and decrease if it's lower.
You'll have to readjust the Z_Max_height in your eeprom settings every time you change the Horizontal Radius.


Tower steps/mm
==============
Eeprom values in Repetier are under Configure >>Firmware Eeprom configuration.  It is listed as "Steps per mm" and should be @ 72.9.

If you used Arduino to set up your printer instead of just the one value in Eeprom there is an X/Y/Z value in the configuration.h file

From the configuration.h file

#define XAXIS_STEPS_PER_MM 72.9
#define YAXIS_STEPS_PER_MM 72.9
#define ZAXIS_STEPS_PER_MM 72.9

X Tower (front left)
Y Tower (front right)
Z Tower (back)

To recalibrate "Use a caliper and move the platform to a spot 10cm or so above the
glass. make a mark on the tower where the carriage is.. then move up or down 100mm and mmeasure how much it actually moved, and your new steps/mm will be the old steps/mm * 100 / caliper result."

eg.
x 80.50 *100 / 100.61
y 80.50 * 100 / 101.24
Z 80.50 * 100 / 101.11