Tuesday, May 5, 2015

Man down!

Metis, my new Wanhao Duplicator 4S, went down last night after an incident involving a snapped piece of filament below the hobbed bolt. When this occurs, there are a couple of steps you can take to resolve the issue, almost none of which are simple. I tried running the extruder motors to get it to feed the piece through the hotend, but as I mentioned, it was below the hobbed bolt. Possible solutions:


  • Heat the hotend to filament temp or just above, and:
    • Run the extruder motor in either feed or retract in the hope that it'll catch and start moving.
    • Push fresh filament through the feed area and into the hotend in the hopes that it'll get the jammed filament moving.
    • Run "extruder floss," aka a strong piece of wire, through the hotend.
  • Use a very fine drill bit in a handle to very carefully drill out the filament. This can cause more trouble than it's worth if you're not careful to avoid scratching up the inside of your hotend, especially if there are plastic pieces.
  • Dismantle the carriage and use pliers to remove the filament.
  • Dismantle the carriage, remove the hotend (if an all metal hotend. I don't know which type of plastic the plastic pieced hot ends use), and soak in acetone (if ABS), gradually cleaning away the dissolved ABS. This is where that drill bit or extruder floss would especially come in handy. Acetone will NOT work if you're using PLA, PET, etc.
These are the ideas that I came up with while trying to clean my jam. In the end, I had to dismantle the carriage, remove the hotend, soak it in acetone because I had used ABS filament, and gradually remove the dissolved ABS. Once I got the jam cleaned up pretty far down, I rebuilt the carriage, heated it up, and used a piece of strong wire as a plunger to force out the filament. I definitely wouldn't suggest using a piece of wire not specifically designed for this task because said piece of wire could have snapped off in the hotend and then you'd really be screwed. Notice I said you. Do this at your own risk.

The whole situation cost me about 9 hours worth of printing time, not including the time I was asleep between last night and today (another 6-7 hours). For what I am doing, that is a huge amount of wasted time. In the process, I nearly had a meltdown as I've had Metis for a whopping 4 days, and this was the second repair I've had to make to her. On the bright side, she's happily chugging away on some stone walls as I speak.

Goodluck and happy printing!