Hello, I’m using my K8200 for over a year now and I’m very happy with it. But now I have a problem I can’t solve:
I’ve swapped the original hotend with an E3D V6 changed the thermistor table etc. all worked well for month but suddently the hotend/extruder jammed.
I’ve cleaned everything pluged in a new thermistor -> still no luck. With further investigation I found out, that the temperature reading is off about 50 to 60°C.
Because everything else(thermistor, pullup resistor, wireing…) is working I think that maybe the ADC or something else with the temperature interface of the board is broken.
So my question is, are there any other pins left on the K8200 board to connect the extruder thermistor to it? If yes do I also need to resolder/rewire the 4,7K pullup resistors?
kind regards
Herb
What thermistor table did you use?
The e3d thermistor should be the same type as the velleman one.
Did you check the readings by swapping heater 2 and heater 2?
That could narrow down the problem.
Hello,
thank you for the quick reply. As thermistor table I used number 5 “ATC Semitec 104GT-2” with 4.7K pullup.
If I heat the hotend up to 240°C and than swap the temperature interfaces the heatbed shows exactly the same value as the readings from the extruder before.
So both interfaces are equal in temperature reading. Where could be the problem? The resistor of the thermistor is about 90K @ room temperature, so nothing special here.
Maybe you can help me further investigate the problem?
kind regards
herb
If both thermistors show the same temperature, how did you tell they’re off 50c?
If you measure on the outside of the Heater block you will get much less values than inside
the thermistor mount.
I checked mine, when i ounted the e3d vs by comparing the shown temp with the actual
temp measured by a thermocouple meter directly inside the nozzle and it gave me about
10-20c less than showed o repetier.
Measuring on the outside of the heater block gave me 50-60 degrees less as well.
The jam can be caused by many other problems as well.
What Material do you print and which nozzle diameter?
Especially black colored filaments tend to block small nozzles because of particles embedded in the filament.
Maybe recheck if the thermistor is correctly isolated. If there is one of the leads in contact to the heater block or else
it will give wrong readings.
Hello, yes I’ve measured the temp on the outside of the heating block. I think the temperature is off by 50°C because normaly I was able to print ABS with 240°C but from the next day to the other the hotend jammed but @290°C I was able to do some printing for about 2h than it jamms again. Than I cleaned everything and also bought a new hotend with new thermistor but the jam presists. It worked all well for month with the E3D and ABS from reprap.cc (atomic green). The extruder is a bulldog XL.
Measured outside the heater block a value about 50c less is quite normal reading.
Again, what material do you print, with what diameter of nozzle?
If your hotend “jams” does the hobbed bolt grind into the filament?
Or does the motor stall?
Hello,
I print with ABS 3mm from reprap.cc. The nozzle diameter is 0.4. The hobbed pulley grinds into te filament but the filament is not moving downwards, because it jamms in the hotend. Retraction is no problem. The pulley is fixes on the motor shaft no slipping etc.
Can you get it back to print if you force the filament through the heated extruder manually?
I sometimes had such issues with black filament, which was impure and thus clogged the nozzle.
After “helping” the extruder by forcibly pushing the filament down the tube while extruding almost
every time the nozzle popped free spitting a large amount of molten plastic.