Extruder

9.0 lb extruder pull force measured on D3D Pro 3 with heater, thermistor, stepper wire plugged in to control panel.
Set motion with knob, held scale and extruder in opposite hands.

Carriage Bearings

Tried plastic bushings, which were not tight. ID was oversized, OD slightly under.
Replaced with metal bearings. They have less friction.
Prior to replacement, carriage would shift from side to side. Now with metal bearings, it goes straight back and forth.
Time: it took 45 minutes to replace the bearings and get machine back to ready.
- Take off the idler
- Take off heatbed
- Take off belt. When replacing belt clamp, put the head to the outside - it should be to inside. Belt threaded right in and out.
- Take out and replace bearings - bearings are tight in carriage with tape.
- Replace all these.
Notes: belt definitely takes longer to connect - the clamp requires a screw, which takes time. One improvement could be a captive nut, right now nut is semicaptive and it falls out.

Modify the carriage so that the set screws go in through side of top rods - the other way did not work, set screws actually didn't hit the rods.