Print The Porto

A collection of tips about 3d printing.

Purge and nozzle wipe starting gcode

Use this gcode to purge and wipe filiment before printing.

Simplified version

M107 ;turn off fan
G28 X0 Y0 Z0 ;home X, Y and Z axis end-stops
G29 ;initiate z-probing
G1 X0 Y0 Z.10 ;move to corner of bed
G92 E0 ;zero the extruded length
G1 F200 E3 ;extrude 3mm of feed stock
G92 E0 ;zero the extruded length

Advanced wipe and purge

M107 ;turn off fan
G28 X0 Y0 Z0 ; home X, Y and Z axis end-stops
G29 ; initiate z-probing
G0 X0 Y0 F9000 ; Go to front
G0 Z0.15 ; Drop to bed
G92 E0 ; zero the extruded length
G1 X40 E25 F500 ; Extrude 25mm of filament in a 4cm line
G92 E0 ; zero the extruded length
G1 E-1 F500 ; Retract a little
G1 X80 F4000 ; Quickly wipe away from the filament line
G1 Z0.3 ; Raise and begin printing.

Categories: gcode, printrbot simple metal

Tags: gcode, printrbot simple metal

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Increase printing speed

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How to calibrate your 3d printer Extruder Steps

Step 1

Enter M501 in the control software of your choice. This will show the current stored settings on your firmware.

The section we are looking for begins with, M92. This sets the number of steps which, in turn controls the accuracy of our printer.

To Calculate Accurate Steps

( Distance to Travel / Distance Traveled ) * Number of Configured Steps

For example, on the (40 / 39.90) * 84.40.

This gives new steps of 84.612 ( we only need a few places of accuracy, the real calculation gives more).

Enter this with the command M92 X84.612 (Make sure the letters are capitalized)

If you're using smoothie firmware it's M92

Example of distance traveled:
Mark 120mm from your reference point.
Extrude 100mm.
After extrusion, the mark is now 17mm from marked point.
120mm – 17mm = 103mm actually extruded.

Step 2 Measuring

We need to measure the amount of filament the extruder is pushing through to make sure we don't over extrude. Mark the filament, with a piece of tape or post-it.

Place a flag of tape 100mm above the extruder.

Extrude 50mm of filament.

Measure the distance from the top of the extruder to the 'flag' of tape, to see how much filament was extruded.

Use the formula above (amount told to extrude/real amount extruded) multiplied by Number of steps in firmware.

Type the new value with M92 Exxx

Save all the settings with M500 and M501 to check the new settings.

Repeat until you get the exact extrusion length you asked to print out.

You can also do this with a 100mm, but measure out to 150mm and extrude 100mm of filament to see if it changes, if so, repeat the steps above until it's accurate.

Categories: Calibration, printrbot simple metal

Tags: Calibration

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