Nozzle swap issues i3 MK3S
I recently swapped my .4mm brass nozzle for a .4mm hardened nozzle. I had zero issues prior and the only reason for swapping was to use copper filled filament. I followed both the online and guide book instructions when swapping, i.e. 285°c nozzle temp, first layer calibration, etc... However now I get melted filament on top of and oozing all around the hot end heaterblock. I made sure everything was seated and allowed the proper gap between the nozzle base and heat block. I’m stumped. I asked Prusa support and was told the heat break needed to be tightened. I’ve tried everything I can think of.
Anyone else ever have this issue?
RE: Nozzle swap issues i3 MK3S
Have you seen the Knowledge base article
https://help.prusa3d.com/en/article/changing-or-replacing-the-nozzle_2069
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 swap issues i3 MK3S
If you have filament leaking from the top of the heater block, the heatbreak was not properly installed down into the block. If the nozzle can still turn to a point that it is possible to tighten the nozzle against the block, the heatbreak is not fully inserted. In other words, if the heatbreak is properly installed, it will be impossible to fully tighten the nozzle hex against the block. There is no magic to that small gap between the nozzle hex and the heater block. It should be there, but just the gap doesn't ensure a seal.
and miscellaneous other tech projects
He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan
RE: Nozzle swap issues i3 MK3S
@joantabb
Yes that is the same link Prusa sent me during a chat.
RE: Nozzle swap issues i3 MK3S
@bobstro
Why would you want to loosen the heat break to change the nozzle? If you hold the heat break in place and don’t allow it to rotate, can you not remove/replace the nozzle and have the proper seating since the heat break didn’t move? This is the part I think I’m messing up on as the wires attached to the heater seem to impede the ability to tighten the heat break. It never feels like it’s tight.
RE: Nozzle swap issues i3 MK3S
[...] Why would you want to loosen the heat break to change the nozzle? If you hold the heat break in place and don’t allow it to rotate, can you not remove/replace the nozzle and have the proper seating since the heat break didn’t move? This is the part I think I’m messing up on as the wires attached to the heater seem to impede the ability to tighten the heat break. It never feels like it’s tight.
You would not want to, but it can happen. The hotend can rotate a bit, and if you straighten the heatbreak out, you can inadvertently loosen it. That's why I emphasize the importance of the gap between the nozzle hex and the heater block after tightening at 285C. If the nozzle isn't tight until the nozzle is flush, your heatbreak -- for whatever reason -- is not inserted deeply enough into the heater block. The block should act as a nut between the nozzle and heatbreak.
You may be at the point that you want to move the printer to a table with good lighting and tear down the extruder far enough that you can clearly see the hotend components and check out what's going on.
and miscellaneous other tech projects
He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan
RE: Nozzle swap issues i3 MK3S
@bobstro
I’ve done that as well. I’ve torn everything down and need to find some thermal paste to put it back together. I ordered some of that from Prusa, along with an assembled hot end. I don’t want to take any chances. Thanks for the input.
RE: Nozzle swap issues i3 MK3S
@gmenear
In the worst case, some folk try to fit shorter than normal nozzles to their Prusa's
the E3dV6 has 7.5mm of thread on the nozzle, the Mk8 and Mk10 nozzles have about 6mm thread, in this case there is about 1.5mm gap which is disasterous...
with the e3dV6 nozzles, if the heatsink twists during dissassembly or reassembly then you end up with a tiny gap between the nozzle end and the heatbreak end. which causes the leak!
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 swap issues i3 MK3S
@joantabb
So is it better not to allow the heat break to move when remove/replacing the nozzle? The video shows the heat break being rotated.
RE: Nozzle swap issues i3 MK3S
I believe the idea of moving the heatsink, is to effectively Preload the heatbreak towards the nozzle to ensure a tight fit when you restore the nozzle. but it onlt works with E3Dv6 Size nozzles, I believe Mk8 and mk10 Nozzles and Olhsson Ruby nozzles are different lengths... If they are shorter, you are in for a world of pain with leakage...
the nozzle should become tight, before the hexagon section touches the heatsink,
If your nozzle tightens against the heatsink, then your heatbreak is too far out of the heat block!
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