12. Detach the thermocouple from the Mightyboard.
The thermocouple attaches to a set of terminals at the bottom right corner of the
Mightyboard. If these terminals are secured by buttons, push the buttons on the
terminals to release the red and yellow leads. If the terminals are secured by screws,
use a small flathead screwdriver to loosen the screws until you can remove the leads.
13. Attach the thermocouple from the new bar mount assembly.
Slide the red and yellow leads on the new thermocouple into the same set of terminals.
Remember to attach them to the "A" terminals rather than the "B" terminals. The
terminals are labeled "Red" and "Yellow" and it's very important that each lead goes
into the correct one. For terminals with buttons, press the buttons on the terminals,
slide the leads all the way in, and release the buttons. For terminals with screws, slide
the leads in and tighten the screws. Tug on the leads to make sure they're secure. You
may find that it's easier to reconnect one lead at a time.
14. Return the electronics bay cover to the bottom of the bot.
Secure it with the eight short bolts and the 2.5 mm hex wrench. Flip the MakerBot
Replicator 2 upright again.
15. Exchange the old thermocouple for the new thermocouple in the extruder
cable.
The extruder cable is a bundle of wires taped together at intervals. At each place where
the bundle is taped, carefully cut the tape, remove the old thermocouple from the
bundle, add the new thermocouple to the bundle, and re-tape the bundle.
16. Slide old the thermocouple out through the active cooling fan mount.
Take the end of the thermocouple closest to the old bar mount and pull it through the
active cooling fan mount. The bar mount assembly should now be completely
detached from your MakerBot Replicator 2. Discard it.
17. Add the new bar mount to the active cooling fan assembly.
Orient the bar mount assembly so the two holes at the left line up with the two holes
on the active cooling fan mount and the nozzle points down, or in the opposite
direction from the extruder cap. Screw the two bolts in using your fingers. Then tighten
them using the short side of the 2.5 mm hex wrench.
Note: At this point you will have two very similar looking pairs of bolts set aside. The
shorter ones are the bolts for the bar mount. The longer ones are the ones you will use
to attach the assembled extruder to the extruder carriage.
18. Connect the new heater wires.
