Klipper started throwing an error and shutting down while trying to heat the extruder. The extruder was cold, which basically meant a heater wire break. Thankfully it was very easy to find. So much for buying a nicer harness. Grumbles aside, I wonder if this wire got pinched when I assembled the chains, which lead to an early failure.
I didn’t have any spare PTFE wire on hand, so I spliced in a length of 16 gauge silicone wire and made sure to land the solder and heat shrink sections well away from any possible motion. I have replacement wire on order, but am tempted to run as is until it fails again…
Disclaimer: I’m not a 3dprinter guy. I want to be, but I never found the time beyond a partially assembled prusa mendel i3.
…however, I have done an extensive amount of wiring, in various environments, a lot of it on moving parts, and what I can say is that wires of these gauges don’t break like this just from movement along that cable chain (or whatever it’s called), unless it’s incredibly cold environment and/or incredibly cheap wiring.
I’m thinking that you’re most likely correct in that it has been pinched.
Agree. The rest of the wire is pristine and you can see plenty of red insulation on one of the open links. In a non-electrical context I would call that self machining and call the red marks on the chain a witness mark. The printer is fully enclosed most of the time with bed fans to help warm the chamber up, so it’s certainly not cold.
I had the same issue after about a year of use. To fix it, I ran the temporary heater power cables alongside the reverse-bowden tube until my replacement wires came in. Learned along the way that the wire size I had been using for a Pharos Rapido was insufficient despite being the recommended size in the docs for standard heaters.
I have a rapido HF. The thing heats up really fast, so it must be pulling some juice. What wire gauge did you wind up going with? It looks like the heater is rated for 115 watts, which is roughly 5 amps.
I think I have 16 AWG on it now, which is definitely overkill. It’s been a wild journey of mods so I’m not even sure what I last installed. I got rid of drag chains and the Huvud CAN board was finicky about voltage drops so I went a bit overboard. I just remember the 24 AWG copper was insufficient for CAN + Rapido HF despite the shorter run and being an IGUS branded cable.
Here is the 16 AWG wire I used: https://www.amazon.com/dp/B089CW1YGM