This thread is a little old but I have been having similar issues recently with my ender 5. I had to replace the heater cartridge and thermistor recently. I was carful not to solder wires together as I have been warned not to. Ihad used a crimp splicer to connect the cartridge wires together. And proper connector for the thermistor. I have had random spikes on the temperature with the ocational thermal safeguard triggering.
I may try to replace the spilce with a proper connector and see if it makes a difference.
One other thing I noticed the when I cool down the got hotend it spikes at that time. One other thing I should mention I also had to replace the part cooling fan a short while ago as it was not spinning for a good 6 month. I repeatedly ran PID tunning with the new parts of course.
Ps is there a possibility this is more due to a part cooling fan blowing to high up or main fan starting to die instead of the thermistor/cartridge issues?
Pushing this post to a new thread, Was tagged on an old one.
Generally speaking, if you get sporadic spikes or drops in the temp is a bad connection somewhere.
I know a lot of people generally put “quick change” connections at the hot end which is generally not an issue. The connections just have to be right and tight. I would concentrate on looking for a loose or weak connection somewhere in the track
I suspect I may have two issues occurring. Any suggestion on what the curves or symptoms would like depending on where loose connection was? thermistor , heater or fan. I suspect I know the answer (little difference) as its a closed loop system. Except for the fan as it’s a mechanical device. I checked all the connectors for play and see if ticking would cause it but no sign yet.
I suspect I also have an issues with the shroud for the part cooling fan. Possibly a crack , I manage to replace it with a printed one directing the blow to the tip. It seem to have resolved the spikes at the moment.
Do you sell custom part cooling shroud for ender5 /3 hot end. Specially for my case compatible with the micro swiss hot end. (same difference)
Generally speaking, thermistors are pretty easy to troubleshoot, when you just boot up the printer it should show something close to the ambient, 20-21 deg. If it shows -14 (yes negative) that means the thermistor has a broken wire or is disconnected somewhere, If it shows 300plus that means the thermistor is shorted out, (both sides are contacting each other). If the varies wildly across say a 30-50 deg spread but never goes limit low or Limit high the thermistor is not seated properly inside the heater block.
Here in the store one of my guys has designed a mount for the micro swiss that places the BLtouch right next to the print head, the other option is one on Thingiverse called the Santana, this is a duel duct shroud that gives you options of what fan you want to use with it. This is generally a good option.
A good plan is if anything is cracked or broken replace it as it can cause more issues than you realize, and always use the silicone sock on your hot end, without it the heat can fluctuate enough to trigger a runaway.
I guess it may not have been a Brocken connection as the spike never went to the limits just the 30 -50 deg spread. The thermal couple was out once and I reseated it but still got swings but not as great or as often. (more like 2 over 4-6 hrs of printing)Likely due to the part cooling fan or may be the sock. it was in bad shape but I replaced from the sales last weekend.
On another topic, for the misroswiss direct drive when is the wear on extruder gear and arm gear past it’s useful life? last round of cleaning a cleaned them up and groove has started on the gears. I’m assuming issues with retraction or flow could be symptoms of the gears. Even after usually calibration steps…
Thanks for your help Jason, took a few attempts to get a clean shroud printed but printing nicely now. Replaced all the wear outables and I think I found the micro swiss model of the shroud.
perfect that’s awesome, Generally, the little “swings” in temp would be rectified by a PID tune, Past that if it gets a little flaky, I would just pull it and replace it. Costs less than $10.