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i want to change the extruder out for a dual/ with a 2 to 1 gear ratio what setting do i need to change?
this is for the Max.

michaels wrote:i want to change the extruder out for a dual/ with a 2 to 1 gear ratio what setting do i need to change?
this is for the Max.

The biggest required change is to set the steps per mm for the new extruder. If you don't know the proper number you will
need to experiment by changing the value in configuration.h and uploading to the Rambo card. You then need to extrude a
known amount of filament like 30mm and measure what was extruded. You will have to repeat this until you zero in on the proper
steps per mm. Perhaps someone using the same extruder could give you the proper number?
There is a great tutorial on calibrating extruders at http://forum.seemecnc.com/viewtopic.php?f=54&t=1163

If the gear ratio is the ONLY thing that's changing (motor and electronics setup remains the same), then just multiply the previous steps per mm by the exact gear ratio to get the new steps per mm.
It's a really good idea to verify by performing the test Eagle described.