Notifications
Clear all

When is the nozzle fan supposed to turn on?  

  RSS
Tim Harper
(@timcharper)
New Member
When is the nozzle fan supposed to turn on?

I've been watching my printer extrude a really messy plastic string lately, and I'm wondering, at which temperature should the nozzle fan turn on? (I have an mk3s). I'm printing PLA plastic and the nozzle is at 215C. It extrudes and it is printing ok but leaving a lot of messy plastic wads otherwise and I'm concerned something isn't working.

If I crank up the fan setting to 20 in the settings then the nozzle fan turns on. But at 10 it does not. Maybe my fan is incapable of running at lower speeds?

Posted : 17/09/2019 10:58 pm
You liked
Nikolai
(@nikolai)
Noble Member
RE: When is the nozzle fan supposed to turn on?

Hi Tim,

The fan usually turns on from the second layer. This is being set in the slicer settings. Please check your PLA profile in the cooling section if it's not happening. For PLA it's usually set to 100% from layer 2.

In the printer settings the number for fan speed is maybe misleading for non IT guys. The value goes from 0 to 255. 0 = 0%, 255 = 100%. And yes, based on the firmware and fan it starts to spin around 10-20 value. That's normal. 

Often linked posts:
Going small with MMU2
Real Multi Material
My prints on Instagram

Posted : 17/09/2019 11:41 pm
You liked
Bunny Science
(@bunny-science)
Noble Member
RE: When is the nozzle fan supposed to turn on?

If this is a new behavior without any recent alterations of the printer, I would suspect a wet filament spool.

Posted : 18/09/2019 12:00 am
Tim Harper
(@timcharper)
New Member
Topic starter answered:
RE: When is the nozzle fan supposed to turn on?

Okay, I was asking because the filament leaks out a lot and it is leading to print issues. I'm using the PLA filament that came with the printer assembly kit and I'm getting this weird extra stringiness and leakiness.

Posted : 18/09/2019 12:00 am
Tim Harper
(@timcharper)
New Member
Topic starter answered:
RE: When is the nozzle fan supposed to turn on?

Ah, yep. https://all3dp.com/2/how-to-dry-filament-pla-abs-and-nylon/

"Excessive stringiness" that totally describes it. I live in the desert! I guess I need to learn how to store my filament better.

Posted : 18/09/2019 12:02 am
--
 --
(@)
Illustrious Member
RE: When is the nozzle fan supposed to turn on?

Ooze is part of printing; but moisture in the filament can make it worse than it needs to be.  The little voids in your Live-Z extrusion hint at moisture, too.

For ooze in general, most of us use an alternate warm up to minimize the ooze before bed leveling.  I heat to about 180c, and most of the PLA filament out there won't ooze too much at that low a temp.  Once mesh level is complete, then do the final heat to print temps.

This post was modified 5 years ago by --
Posted : 18/09/2019 3:30 am
Nigel and liked
Nikolai
(@nikolai)
Noble Member
RE: When is the nozzle fan supposed to turn on?

It looks like your live-z is a little bit too low. Raise up the nozzle a little bit. Plastic has no way to escape and the pressure is building up. Because you're not printing second layer, the plastic under pressure is just being released in air.

Please try to print couple objects. It's usually no issue as it will normalize after couple layers.

Often linked posts:
Going small with MMU2
Real Multi Material
My prints on Instagram

Posted : 18/09/2019 6:38 pm
Nigel liked
Share: