Should the extruder fan always be on?

[Ken Hoven]

I have the M2 and my extruder fan is not on. Should this run all of the time or does it come on and off as needed.

I just want to make sure its ok to be off.

Regards,

Ken

[Ketil Froyn]

You don't need to run the cooling fan if each layer takes long enough to cool down before the next layer. Your slicer should usually switch it on automatically if layers take less than a predefined time, for example a minute. However, I usually run with the fan always on (not at full speed though), except for the very first layer, but the fan speeds up for stuff like small layers and bridges. Haven't done extensive testing to see if always on improves my results, though, I've just always done it.

--
You received this message because you are subscribed to the Google Groups "MakerGear - Make Today, Change Tomorrow" group.
To unsubscribe from this group and stop receiving emails from it, send an email to makergear+...@googlegroups.com.
For more options, visit https://groups.google.com/groups/opt_out.
 
 

--
-Ketil

[Ken Hoven]

I just wanted to make sure.

There are 2 fans... the lower one is on but the upper fan is off. Is that ok?

Thanks,

--
You received this message because you are subscribed to a topic in the Google Groups "MakerGear - Make Today, Change Tomorrow" group.
To unsubscribe from this topic, visit https://groups.google.com/d/topic/makergear/T2cs4x7GjYQ/unsubscribe?hl=en.
To unsubscribe from this group and all its topics, send an email to makergear+...@googlegroups.com.

[Ketil Froyn]

Using this picture (first one I found on google images) as a reference:

http://columbusideafoundry.com/wp-content/uploads/2012/11/IMG_2682.jpg

the smaller top one should always be running, and the bottom one doesn't have to be on. The top one makes sure heat doesn't creep up the hotend, as far as I know, so you want that on at all times, at least when your hotend is hot. If it's not on, you should be able to start it with a M108 S155, and switch it off with M108 S0. If that doesn't work, you probably have a loose connection.

Sorry if I was initially confused about which fan you meant.

Cheers, Ketil

[Ken Hoven]

M108 S155 operated my electronics fan, do you know the code for the extruder fan?

Its a pre-assembled unit that was working fine until now.

Regards,

Ken

[Ken Hoven]

Hi again... no worries... I found the issue. 3 of the fan blades broke off and one was jamming the fan.

Thanks,

Ken

[Karl Williams]

I had to replace the washers that separate the fan from the laser cut plastic 'M2' cover on mine because they were too small and the fan would not turn at all. The laser cut plastic cover was so close to the fan that it was stopping the blades from turning. I still need to add a couple more washer or just remove the cover because I can hear the fan blades hitting the cover during fast X-Y moves. 

[Raymond Caron]

Thanks for the post Karl. 

I just realized my extruder fan wasn't running and I couldn't figure out why at first. Your post solved the problem. 

[Bryan Boettcher]

You guys still have your fan covers on?

--

[Charles]

I don't use the fan covers they add extra weight (mass) to the extruder, just keep your fingers and tools away when they are running.

[Bryan Boettcher]

Yeah I figured the little plastic fans probably aren't the dangerous part of the printer and took mine off as well.  That, and I also run a 40mm print fan (straight 24v, ball bearing fan, the thicker 3/4" profile)

[Tony Shulthise]

Those fans are pretty bad about failing either by broken blades or the bushings fail. What is needed are ball bearing fans vs bushing fans

[Tony Shulthise]

BTW, the top fan should always be on.

[Bret Allen]

Ken, Maybe I missed it but I didn't see that anyone answered your question regarding the fan control M code. It's M106 for the lower bed fan.