Heater

Replaced heater with a halogen bulb.
Testing. So far 40 hours (one full print of D3D Pro Parts) + 15 hours of normal duty testing at 45C, natural cycling.
Using 2 second on - off cose, 500k lines, 125,000 cycles, totaling 500k seconds = 5.8 days of cycling.
This amount of cycling (full on-off) is equivalent to about 15x more than this = 90 days or so, as each natural cycle takes about 1 minute.
Gcode Test file - [1]

Bed Clamp

Can't bed clamp be used instead of autoparallel/endstop holder pieces? Unique part count reduction.

It looked like bed burned out, but opening it up, all was fine. Turns out the SSR went bad. The light on SSR turns on, but power is not conducting. Have not seen a bad SSR to date. Failure rate is about 1/25 so far.
Add a ground wire to bed metel. Paint bottom plate. Do not paint top plate or conduit so top plate and conduit conduct and are both grounded. Bottom plate is isolated by carbon fiber blanket and plastic bed holders, so there is limited shock hazard coming from bottom plate. Suggestion - run a ground wire through the wire loom, screw it in to conduit. Keep ground wire on GFCI, run new ground wire from GFCI ground screw to bed. Note that ground wire is not necessary for the GFCI to trip properly, but the ground wire will still protect ground faults independent of the GFCI protection. True?

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.

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.

See D3D_Plotter_Log#Fri_Aug_28.2C_2020 for results
Bolt hole in plotter is oversized, screw is loose now
Back side of pen hole should be a groove so pen stands vertically up, not a round which allows lateral motion.