Another take on a drive block for the extruder of the Zortrax/Wanhao D6/Monoprice Ultimate clonage for flexible filaments.
Version 2 has a very tight fit for the 10.8mm diameter, 38 tooth Robotdigg Filament drive gear 4 flat shaft for nema17 stepper (RDGFDB) and the Micro-swiss lever for the Wanhao D6. The original D6 drive gear will also fit. You may have to sand the inner diameter a little. Clean up the print by drilling through the filament guide and smoothing the upper entry. I printed this in PETG.
I can finally print large projects in Ninfaflex on the Wanhao D6.