Fan shroud attached to hot end melting

[Print_This]

Has this ever happened to you guys?
the fan shroud that is attached to the hotend in the center made of ABS started to melt through the hotend right to the tip and drip down to print area.
i have only been printing PLA and noticed the drips but actually were black and the fan housing was blue but as i took it out noticed it turned black maybe because it was burning?
anyways the facts,
i print the PLA about 180-190 depending which color etc.
and the shortest time i print before it starts dripping is maybe 30 minutes,

i wouldn't had thought it would melt since im only printing PLA @ 185-ish

any one else have this issue? maybe my sensors our of whack?

so my next question is, do i really need that fan installed their anyways?
i have 2 other fans blowing underneath that i downloaded from repables. but i took the hotend fan off temp.

thanks for any insight.

[int2str]

Has this ever happened to you guys?

No.

the fan shroud that is attached to the hotend in the center made of ABS started to melt through the hotend right to the tip and drip down to print area.

Which hotend? Stock?
Which fan shroud? Stock?

so my next question is, do i really need that fan installed their anyways?

ESPECIALLY if the hotend gets hot enough to melt ABS, you NEED that fan. It's not for the part like the 2 fans you mentioned underneath. It's there to keep the PEEK (material) section of the hotend from melting and to keep the filament inside the hotend from melting before it hits the nozzle. Because you can't push a "wet noodle"...

Are you sure it's the fan shroud melting and not PLA oozing out somewhere?

And yes, if your hotend gets that hot up top, somethings wrong with your thermistor.

[geneb]

The ABS fan shroud isn't going to drip like that unless someone accidentally made one out of PLA (unlikely) or your hot end is actually close to 240C. I would STRONGLY recommend you validate the thermistor reading against a thermocouple.

g.

[JohnStack]

I've had my peek fan shroud get burned a little bit but not melt and then I followed someone's suggestion and kept it running full time..

[Eaglezsoar]

That is the most important fan that you have on your printer. It absolutely has to be on when the hotend is heating or is hot.
I like to connect that fan directly to 12V so that when the printer is on that fan is on. Irregardless of how it is connected, it has
to be on 100% when the hotend is hot. Do not ever disconnect that fan or turn it off, it is that important.
Even the all metal hotends have a fan blowing on the fins and it also must be on when the hotend is on.
The best thing for you to do is too follow Gene's instructions in the manual on how to connect that fan and for the rest of your
printer's life, make sure that fan works. If it breaks or shuts off for any reason do not print until the fan is fixed. It is that
important.

[Print_This]

The ABS fan shroud isn't going to drip like that unless someone accidentally made one out of PLA (unlikely) or your hot end is actually close to 240C. I would STRONGLY recommend you validate the thermistor reading against a thermocouple.

g.

ok thanks for the replies guys, so i know its 100% the fan shroud dripping because when i took it off its melting etc.... i have checked my hotend with a infered meter and its within 5 degrees of the display reading so im guessing the fan shroud was given to me made out of PLA which makes sense why it was melting at a lower rate.

i see so many videos on youtube people running without that fan which is why i asked.
but i will remake it with ABS and reattach the fan for sure.

thanks for the help/tips!

[Eaglezsoar]

The ABS fan shroud isn't going to drip like that unless someone accidentally made one out of PLA (unlikely) or your hot end is actually close to 240C. I would STRONGLY recommend you validate the thermistor reading against a thermocouple.

g.

ok thanks for the replies guys, so i know its 100% the fan shroud dripping because when i took it off its melting etc.... i have checked my hotend with a infered meter and its within 5 degrees of the display reading so im guessing the fan shroud was given to me made out of PLA which makes sense why it was melting at a lower rate.

i see so many videos on youtube people running without that fan which is why i asked.
but i will remake it with ABS and reattach the fan for sure.

thanks for the help/tips!

You cannot get an accurate temperature from a hotend using an infrared thermometer. They cannot read it correctly because of the reflectivity of the aluminum. You must use
a thermocouple meter and stick the thermocouple into the hotend down to the nozzle to get an accurate reading.