nozzle temp
if i hold the nozzle fan i can get the temp of the nozzle to go to the 210 but when i let it go the temp drops to 162. is there a solution to this problem?
RE: nozzle temp
if i hold the nozzle fan i can get the temp of the nozzle to go to the 210 but when i let it go the temp drops to 162. is there a solution to this problem?
Such an extreme drop in temperature is unusual. I think that either the thermistor or the cartridge heater is not working properly. I would check all wires and connectors.
Thermsitor internal resistance = 100kohms at 25 degrees C. Room temperature
heating cartridge 12V/40W internal resistance = approx. 3.6ohms
heating cartridge 24V/40W internal resistance = approx. 14.4ohms
Statt zu klagen, dass wir nicht alles haben, was wir wollen, sollten wir lieber dankbar sein, dass wir nicht alles bekommen, was wir verdienen.
RE: nozzle temp
ugh i need to figure out how to do that. can you recommend any videos?
RE: nozzle temp
if i hold the nozzle fan i can get the temp of the nozzle to go to the 210 but when i let it go the temp drops to 162. is there a solution to this problem?
Obvious concern is whether the fan is being directed onto the heater block and nozzle improperly. From your description, I'd expect removing the fan shroud completely to allow the nozzle to fully heat. Check the fan shroud alignment. Consider adding a silicone sock to insulate the block from the fan.
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RE: nozzle temp
I once did the work and tested the temperature drops on an original well working MK3 (without silicone sock):
| fanspeed bin. 0-255 | fanspeed in % | max. possible temp bef. mintemp | |||
| 255 | 100% | 232⁰C | |||
| 230 | 90% | 236⁰C | |||
| 204 | 80% | 238⁰C | |||
| 179 | 70% | 258⁰C | |||
| 153 | 60% | 277⁰C | |||
| 128 | 50% | 298⁰C | |||
| 102 | 40% | 305⁰C | |||
| 77 | 30% | 305⁰C | |||
| 51 | 20% | 305⁰C | |||
| 26 | 10% | 305⁰C | |||
| 0 | 0% | 305⁰C | |||
Fullspeed should be no problem at 210degrees C.
With MK2.5 it will probably be similar.
Statt zu klagen, dass wir nicht alles haben, was wir wollen, sollten wir lieber dankbar sein, dass wir nicht alles bekommen, was wir verdienen.
RE: nozzle temp
Did you ever find a solution to this? I am having similar issues, though not quite as dramatic of a drop. Just finished MK2 >> MK2.5s upgrade, version R4. No MMU in my case.
RE: nozzle temp
I believe I found my issue. Hotend heater resistance is 5.7 ohms, which is consistent with a 25W heater. Should be 40W. Though the leads are red at the head, they are blue where they come out to the panel (again consistent with 25W heater). My printer is a mk2 ordered in 2016, so I guess that's what they used back then. It can't keep up with the bigger blower used in the new house extruder.
RE: nozzle temp
@thebrucecrowder
also check your power supply voltage, my mk2 was lower than 12 volts, there is an adjuster by the power connectors on the power supply, under the plastic cover
regards Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
RE: nozzle temp
@joantabb
Thanks so much for the input. I did check the input voltage (on the heat connector while preheating) and measured 11.9 for the nozzle and 11.6 for the bed. I got a new heater cartridge (from filamentone) and though is says 40W/12V, it only measures 5.2ohms. So the output power will be 12^2/5.2 = 28W.
I'm going to start a new topic.
RE: nozzle temp
Try my nozzle fan shroud fix
https://www.prusaprinters.org/prints/56604-mk25-fan-shroud-fix