RepRap Calculator v3

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Useful set of calculators for RepRap users.

Printing

Optimal print settings

This should provide you some solid starting settings. It basically uses all rules I use for my prints. As bonus it shows you some estimates what to expect (maximum overhang angle, ...). For starters just choose your nozzle diameter. In second stage you can tweak the predicted settings. When some of them are not usable, warning will pop up.

Nozzle diameter
Predicted free extrusion diameter Suggested layer height

Free extrusion diameter in mm

Layer height in mm

Width Over Height

  • Multiplier, gives you line width after multiplying layer height.
  • Affects print detail.
  • Affects maximal overhang angle possible.
  • WOH smaller than 2.0 produces weak parts.
  • WOH bigger than 3 decreases the detail of printed part, because of thick line.

Warning! WOH is under 2.0, that will cause your parts to be weak and easy to break.

Warning! You'll have troubles printing infill because your extruded line cross section area is smaller than minimal extrusion cross section area for stable extrusion. Try bigger layer height or bigger WOH. If you need to use this, set up 100% infill. Ideally get a smaller nozzle for this job ;-)

Warning! You will be extruding too much from your nozzle. It will make the unsupported line (infill) soggy and cause many other problems. Try smaller layer height or smaller WOH.

Free extrusion cross section area Minimal extrusion cross section area for stable extrusion Line width Extruded line cross section area Suggested bridge flow-rate multiplier Predicted smallest feature printable in XY Predicted maximum overhang angle

Firmware settings

Steps per mm for leadscrews

The result is theoretically right, but you might still need to calibrate your machine to get the best prints. This is a good start though.

Motor step angle

Driver microstepping

Leadscrew pitch

Motor pulley teeth count Leadscrew pulley teeth count
1:1 for direct drive, like a Prusa.

For example: 2560 = (((360/1.8) * (1/(1/16)))/1.25h)*(1 / 1)

Set it in configuration.h in your firmware.

Steps per mm for belts

The result is theoretically right, but you might still need to calibrate your machine to get the best prints. This is a good start though.

Motor step angle

Driver microstepping

Belt pitch

Tooth count

Steps per mm = ((360°/Motor step size°) * (1/Driver microstepping))/(Belt pitch * Tooth count)
For example:
80 = ((360°/1.8°) * (1/(1/16)))/(5 * 8)

Set it in configuration.h in your firmware.

Extruder calibration

Extruder calibration tutorial

Extrude button clicks

Extruded length per click in host

Old extruder steps/mm (50 is same as in the linked article)

Marked length on filament (30 is same as in the linked article)

Extruder steps/mm = ( extrude button clicks * extruded length per click * old extruder steps/mm ) / marked length on filament


Thermistor lookup table generator

Kindly done by nathan7. This script allows you to create lookup table for thermistors for use on Arduino based electronics. Take the data from the thermistor datasheet. If you don't have a clue what datasheet is, ask someone on IRC to generate the lookup table for you.

r0 t0 Beta r1 r2 Sample count
Thermistor lookup table

Axis calibration

If you move axis in sw for 10mm (demanded length) and actual machine moves for only 8mm, you need to do this calibration. This will calculate new steps per mm value for the axis we calibrate.

Expected move length

Actual move length

Old steps/mm

new steps/mm = (expected move length/actual move length) * old steps/mm


Convertors

mm/s to gcode feedrate

The standard feedrate as used within gcode is in millimeters per minute. For example:

G1 X90.6 Y13.8 E22.4 F3000

gives a feedrate of 3000 millimeters per minute. The calculator below will convert the millimeters per second speed used in Skeinforge to the feedrate used in gcode.

mm/s

Feedrate = (mm/s)*60


gcode feedrate to mm/s

The standard feedrate as used within gcode is in millimeters per minute. For example:

G1 X90.6 Y13.8 E22.4 F3000

gives a feedrate of 3000 millimeters per minute. The calculator below will convert the feedrate used in gcode to the millimeters per second speed used in Skeinforge.

Feedrate

mm/s = Feedrate/60