We've designed the H-Series to have easy hotend and nozzle changes. Follow this procedure:
- Make sure the filament is retracted from the nozzle (approx 20mm)
- Rotate the turret so you have access to the nozzle (call up Tool2 to access Tool1, T3 -> T2, T4 ->T3, T5->T4, T1 -> T5)
- Make sure the tool is still hot (>180C) and loosen the the nozzle with the 7mm nut driver
- For safety, LET THE HOTEND COOL DOWN.
- If replacing the Heatbreak, remove the (2) M3x5 socket head screws that attach the heatbreak to the extruder body. By hand, unthread the heatbreak from the heater block. (Note: if a leak occurred in the hotend and plastic made its way to the threads, it may be necessary to perform this step while the hotend is still hot. Leather gloves are highly recommended.)
- To reassemble, thread the new heatbreak into the heater block until the back surface of the threaded portion of the heatbreak is approximately flush with the back surface of the heater block (see diagram below). Before reinstalling the hotend to the extruder body, check that the PTFE liner is not discolored. This is more likely with a standard hotend (shown on the right in the diagram). If the PTFE does look badly discolored (more than ~1mm of browned region), replace it before continuing with the rest of the assembly.
- Reinstall the hotend to the extruder block with the (2) M3x5 socket head screws. Install these screws gradually by 1/2 turns alternating between them. Finish by torquing them to 6in-lb.
- Thread the new nozzle in by hand to get it started, then tighten it down with the nut driver (Use pliers to apply countertorque to keep the hotend straight. Apply approximately 8in-lb of torque. At this point, check that the hex of the nozzle is not in contact with the surface of the heater block. As shown in the diagram above, there should be a gap of 0.5~1mm. If this is not the case, disassemble again and thread the heatbreak into the heater block another 1/2 turn.
- Heat the hotend to over 200C, and snug the nozzle again to ensure a good seal to the heatbreak. Apply approximately 8in-lb of torque.