Drehmoment Düse Volcano?

[ManAtArms 59]

Ahoi!

 

Habe mir vor kurzer zeit einen Kobra 2 Pro zugelegt und da habe ich mir diese Woche Gedanken gemacht, wie ich die Düsen wechseln werde.

 

Für den UM2E+ verwende ich ein Olsson Nozzle Tool das die Düse mit 0,5Nm anzieht, was bei dem kurzen Gewinde Sinn macht.
Jedoch verwendet der K2P Volcano Düsen (soweit ich das rausfinden konnte), die wesentlich länger sind.

 

Leider konnten mit weder das 3D Druck Forum noch Anycubic selbst einen passenden Wert nennen, der für die Düse optimal wäre.

 

Ich habe mir auch schon Drehmomentschlüssel mit fixen Werten ausgedruckt mit 1,5 / 2.0 / 2.5 Nm.
Es gibt auch noch welche darunter mit 0.5 und 1.0 Nm, aber 3.0 Nm will ich nicht ansatzweise probieren da das doch etwas zuviel sein könnte und in den Kommentaren einer seine Düse damit abgebrochen hat.

 

Was meint ihr dazu?

 

Edited March 22 by ManAtArms

[GregValiant 1,253]

You have a lot of thread engagement there.  The specification for a steel M6 into a steel thread is 3.84Nm.  The weak point is threading them into a soft aluminum block.

Repeatedly changing nozzles and tightening them will shorten the life of the block as eventually the threads will strip.  The brass of the nozzles has much higher shear strength than the aluminum heater block.  The nozzles will eventually win.  The only real fix is to put a threaded insert (heli-coil) into the heater block.

 

For the short nozzles in my hot end I use the precise specification "Snug".  As long as molten plastic can't get by you are good to go.

[ManAtArms 59]

My guts say i should not use more than 2Nm for this, but i could be wrong too since i habe no experience in this section.

 

The anycubic support gave me a great recommendation: if the nozzle can´t get tighter, make it tighter.
If i follow this i have a two part nozzle very soon.

 

I also can screw it in with the regular wrench that was included, but i have almost no feeling in my right hand if something is thight or loose, i got a nerve damage there so i am depended on torque wrenches.

[GregValiant 1,253]

There are two things that can happen

1. If the nozzle isn't tight enough then plastic can squeeze past it.  It will collect in the silicone boot and then drip onto your print.  There have been instances where the plastic cannot move down so it goes upward.  That creates a real mess.
2. Over-tightening the nozzle can stress the threads and repeated high stress can lead to stripping the threads.  You have enough thread engagement that 2Nm should be fine.

After tightening the nozzle and starting a print, just keep an eye on it.  If you see a drip forming then you will need to tweak it a little more.  I would inspect under the silicone insulator after the first print just to make sure it's OK.

 

The hot end should be warmed up before removing or installing a nozzle. ~180° is good,  They come out hot enough to burn you so make sure you have needle nose pliers or industrial tweezers ready to handle it.