Extruder swap

K8200 3D Printer K8200 - Your printer, creations, and ideas for imp
1

Hi there can some tell me if at a later date i want to change back to the 3mm extruder
will have to change the rod and replace the old one and re/ firmwae will that have to changed

2

You should be able to swap the stock extruder back onto the machine in place of the K8203 without any other physical modifications. You will need to re-flash the firmware to have the correct STEPS_PER_UNIT for the stock setup, however.

I’m not sure what “rod” you are referring to? If you mean the Z axis upgrade, you can use this with the stock extruder - it is a completely separate upgrade.

3

the rod i am speaking about is the K8204 Z axis upgrade with the finer threading

4

Sure, you can leave the z-axis upgrade in place with either extruder.

When you installed both the K8203 and K8204 upgrades, you would have changed a line in Configuration.h to modify the STEPS_PER_UNIT for the Z axis and also for the exturder, like this:

#define DEFAULT_AXIS_STEPS_PER_UNIT   {64.25, 64.25, 2133.333, 150}  // K8203+K8204

The values in the list are for the X, Y, Z, and Extruder motors, respectively. To restore the settings for the stock extruder, set the steps per unit back to the original value of 600.

#define DEFAULT_AXIS_STEPS_PER_UNIT   {64.25,64.25,2133.333,600}  // K8204

Then reflash your firmware and reload your EEPROM settings by sending gcode M502 followed by M500.

I haven’t tried this myself, but it may be possible to edit the steps per unit in the EEPROM settings directly, which would mean that you wouldn’t have to reload the firmware. This might be easier if you intend to switch back and forth between the two extruders regularly.

Personally, I prefer to have the actual machine values hard-coded into the firmware.