With my new Tronxy printer I was able to print the mounting hardware to upgrade the hotend on my DaVinci 1.0A to a E3D v6 hotend.
Printing the Mounting Hardware
I originally printed the mounting adapters by Thingiverse user oscahie, thing:707530. I found a few issues with this adapter during assembly and I modified it to better fit my needs, thing:2220188. Specifically I found that the lower mount did not account for the thickness of the extrusion idler mount, see the photos below. The original lower mount is black while the modified lower mount is blue. I also adjusted mounting hole dimensions to match those of the NEMA17 extruder motor, the original design may have accounted for shrinkage that I do not see. Finally I made a slight modification of Z thickness to provide better clamping force on the E3D v6 since the original reqired sanding before making contact with the hotend mounting shaft.
Mechanical Assembly
For assembly I followed the directions given by oscahie and the XYZ Davinci 1.0A 3D Printer now with an E3D v6 hot end video series by StevenQ-NE-UK on YouTube. I deviated from the wiring instructions in an attempt to provide a cleaner wiring harness and connections.
Wiring Harness and Connections
I cut the off the two pin connector from the original wiring harness of the heater cartridge and then spliced in the E3D heater cartridge using 2mm RC bullet connectors, these came with the BLDC motors for my quadcopter but I never used them. They work great for this since they are rated for high current and best of all cost me nothing extra. After soldering them to the wires I installed heatshrink to prevent the connectors from shorting to each other or the printer frame.
I attached the E3D 12V fan to the 12V and ground rails directly on the main board. The connectors on the left of the board expose these pins and I was able to wrap and solder the wires to these points. The video series by StevenQ-NE-UK goes into further detail about this. I added a male connector to be able to adapt these wires to the cable provided in the E3D kit.
The YouTube videos suggest connecting the new thermistor to the small PCB that was originally mounted by the extruder. I decided to remove this PCB and connect the thermistor directly to the controller. Using a multimeter I determined that the black and yellow wires on the six pin connector are thermistor inputs. I spliced in the thermistor with the cable provided with the E3D kit and a male header. Shrink wrap and kapton tape ensure everything stays together. Since the thermistor and fan cables are the same color I labeled the wires accordingly, I have a label maker and am not afraid to use it! Future me will be thankful.
Thermistor Troubles
Now for the moment of truth. I updated the firmware to use the correct thermistor conversion table and then turned on the printer. It must have been a warm day because the thermistor was reporting that room temperature was about 80°C. Hmm something’s not right. I adjusted the thermistor setting in the firmware to use the old conversion table and the temperature reading was closer to actual room temperature but when I heated up the hot end and measure the actual temperature with a temperature probe the actual temperature was 30°C or lower than what the printer was reading! For some reason the thermistor was not being read correctly.
After much frustration and troubleshooting I found a forum post with a few commenters experiencing the same problem. This lead me to Issue:#104 on the Repetier GitHub page that suggested a possible solution to using a non original thermistor on the DaVinci 1.0. After removing R29 on the mainboard the temperature reading was within a few degrees of the thermocouple. See the below photo of R29 removed from the mainboard.
Now all that remains is adjusting the software settings in Simplify3D to produce perfect prints. I am still trying to dial those settings in.
April 2017 Update:
I also printed this layer cooling fan that I found on Thingiverse and then modeled up a 40mm fan adapter to use the fan that came with the DaVinci 1.0. I have been able to print a 20mm calibration cube with ok results but I have had to slow the printer down to 20mm/sec for all travel making anything I print take twice as long as my Tronxy Prusa i3 clone. The quality is not anywhere near my other printer. The DaVinci just may not be worth spending anymore time on, for the cost of the new nozzle I could have bought half of a second Prusa i3 clone not to mention the time. I may devote some more time to the DaVinci printer but I think it will take a major overhaul since I have discovered a majority of the mechanics are worn out. Then again it may only be worth salvaging the motors and anything else to build another better printer.
SD Perry 