RepRap Firmware settings

The Duet hardware is probably one of the best controller boards out there, and the same goes for its firmware. There are no major surprises or difficulty with settings due to its design and setup for the Flex3Drive is very straight forward.

As you will know, RRF uses a config file which can be edited through the web-interface, or using a notepad type editor. There are several sections within the config file for different parts of the setup. We only need to focus on E axis settings.

The settings below are the parameters that need to be adjusted, along with the suggested values for a safe working baseline to tune up from.

Some of these settings can be tuned during initial testing, such as motor current, Acceleration and jerk for the E axis.

Other parameters are pretty much set and forget such as microstepping and interpolation for the E axis.

For Slicer settings, do the following

1. Get actual filament diameter by measuring in several places with calipers and taking the average value and enter this into the slicer settings

2. Set all nozzle width settings to actual nozzle diameter, and set to manual in S3D.

3. Set extrusion multipliers to 1 or 100%.

4. Set Retract speed to 15mms and retract length/distance to 1.5mm

5. Disable any coast/wipe settings and disable pressure advance if used. No primary calibration is required.

Set running direction of E axis motor. This will be dependent on the motor connection to the board

M569 P3 S0 (set to 0 or 1)

Configure microstepping to your preferences for the XYZ axis independently from the E axis

M350 X16 Y16 Z16 I1

Configure E axis microstepping to x8 with interpolation OFF

M350 E8 I0

Set E axis steps per mm here to 1900

M92 X160 Y160 Z160 E1900

Set E axis jerk/deviation/instantaneous speed change to 0.1mm/sec (6mm/min)

M566 X1500 Y1500 Z1500 E6

Set maximum E axis speed (in mm/min)

M203 X18000 Y18000 Z18000 E2400

Set E axis acceleration

M201 X2000 Y2000 Z2000 E120

Set E axis motor current

M906 X1500 Y1500 Z1500 E400 I60