I got a new Biqu H2V2 for my Ender 3 pro , since myold hotend started getting unreliable and that was a great excuse for yet another upgrade.
I wasn't happy with the carriage holder I printed, so I wanted to print a new one. After afew hours of printing, I needed to abandon one part, since it was incredibly messy with blobs of PLA gooped on the print. Since I needed the new carriage mount, I didn't think anything off it and simply abandoned that part and continued the other ones.
Today, I saw that the heating block is completely gooped up with PLA (see pictures). So now, I got two questions:
- How should I remove that gunk? I was thinking o| carefully peeling of everything without the silicone sleeve while the hotend is at a low PLA-bending temp, like 150°C, or 175°C.
- What caused this? Flowrate too high (the prints look the part)? Too fast extrusion? Heatcreep?
Thanks in advance. (:
Harumpf 🙄😤. It came like that. I only attached the extruder to the printer. I didn't expect that I need to open it up.
Maybe I should have fastened the nozzle, though.
@Prunebutt @Fenderfreek
Its not about torque only.
If build up correct, the nozzle flange does not touch the aluminium heater block. There must be a gap, can be a tiny gap.
You dont want to screw the nozzle against the block, but you want to screw the nozzle backside face (around the filament bore) against the heatbreak end face. This is the place where you close the oozing hole, the threads are not tight against liquid plastic.
So that means I need to teardown the extruder and check the seal of the heatbreak?
@Prunebutt
There is no seal like an o-ring.
It is bare metal to metal surface contact.
If there is a gap between nozzle backside end and heatbreak because the outer hexagonal part of the nozzle hit the heater block first (before the nozzle get tight at the heatbreak), it will leak through the treads and ooze out on the top.
If you can rotate the heaterblock after heating up the nozzle, then there is proof of the inside gap.
On a new hotend i disassemble it before mount it into the printer, screw in the nozzle in first and then turn it back half a turn.
Then screw the heatbreak in until it reaches the nozzle. Install it to the printer, heat to max used temperature, and tighten the nozzle again.
The heater block has bigger thermal expansion, so it tends to get loose by heating up.
If done correct you will never have problems like this, if the mating surfaces are even and not damaged.
That's what I meant with "seal". 😅
Thanks for the advice. Gonna implement it.
@Prunebutt Yw