Extruder fan specification ?  

Re: Extruder fan specification ?

Since I have started to use my HEPA/activated carbon filter inside the enclosure, the noise from the fan has become negligible compared to the noise of the filter fans 😀 😀 😀

Re: Extruder fan specification ?

temperature and noise... But then the fan is controlled in PWM, and for any value you set beside 255 you'll get a high pitched coil wine. That coil whine is even more annoying than the fan itself... absurd. Back to 255 and 100 ohm resistor.

You can filter the PWM signal, I did that for my Velleman k8200 fans, works very well:

http://bukobot.com/pla-print-cooling-fan

Just a diode and a capacitor.

Carsten

Re: Extruder fan specification ?

Ah! at last, a benefit of Age...

I can't hear the whine from the PWM...

😀

Joan

Re: Extruder fan specification ?

Just a diode and a capacitor.

A resistor and capacitor would work better to generate an analogue voltage from a PWM signal (which is entirely positive; the diode will only serve to drop the voltage by about 0.6V).

The resistor value needs to be calculated, based on the load such that the charging and discharging of the capacitor is pretty much constant.

Peter

Re: Extruder fan specification ?

Yes this is maybe right, but as I did understand the diode is something that would permit the discharge of the cap to the output driver. However, I did use it in a 3d printer and some pwf fan control for a different project and it ot only eleminates the whine but also ensures that the fan starting reliable for low PWMs!

Carsten

Re: Extruder fan specification ?

Carsten

Unreliable fan starting is more likely with a low analogue voltage than with PWM, where at least it is "kicked" into operation by a 12V pulse.

I play around with model railways; the same is true of the motors in the locos. It is much easier getting consistent low-speed running using PWM at full voltage (DCC digital control) than when using a low voltage analogue controller.

Peter

Re: Extruder fan specification ?

I never compared analog low voltage with PWM at low settings. I only gave my experience that with that circuit my fans do not wheeen and start much more reliable at low PWM. YMMV of course.

Carsten

Re: Extruder fan specification ?

Carsten

Many fans nowadays (even very cheap ones) usually come with some on-board circuitry designed to prevent reverse polarity and that same circuitry may also be designed to coax the fans to start up at low voltages; some sort of boost/pulse circuitry would be very easy to implement so your experiences may be totally correct and simply depend on the different electronics employed by the various fan manufacturers.

Peter

Re: Extruder fan specification ?

I would like to revive this thread.

Is anyone using a 40mm Noctua fan at the moment?

Have there been heating problems? Melted ABS parts near the heatsink?

If yes, can anyone post the link of the adapter they are using? it seems the one from Patrik is not there anymore.

Re: Extruder fan specification ?

I would like to revive this thread.

Is anyone using a 40mm Noctua fan at the moment?

Have there been heating problems? Melted ABS parts near the heatsink?

If yes, can anyone post the link of the adapter they are using? it seems the one from Patrik is not there anymore.

I am using a 40mm Noctua fan with the adapter from GrabCAD.

I was also able to get my hot end up to 410C with no ill effects.

Re: Extruder fan specification ?

I would like to revive this thread.

Is anyone using a 40mm Noctua fan at the moment?

Have there been heating problems? Melted ABS parts near the heatsink?

If yes, can anyone post the link of the adapter they are using? it seems the one from Patrik is not there anymore.

I am using a 40mm Noctua fan with the adapter from GrabCAD.

I was also able to get my hot end up to 410C with no ill effects.

Is that a typo? 410C hotend sounds wrong. 😉

Re: Extruder fan specification ?

I would like to revive this thread.

Is anyone using a 40mm Noctua fan at the moment?

Have there been heating problems? Melted ABS parts near the heatsink?

If yes, can anyone post the link of the adapter they are using? it seems the one from Patrik is not there anymore.

I am using a 40mm Noctua fan with the adapter from GrabCAD.

I was also able to get my hot end up to 410C with no ill effects.

Is that a typo? 410C hotend sounds wrong. 😉

No, it's not a typo. See this thread.

Re: Extruder fan specification ?

no problems whatsoever with stock fan + 100 ohm resistor either.

I was thinking to replace the nozzle blower now, as it's currently the most noisy thing. Sunon makes good blower replacement with 2cm depth, which are more silent (nozzle duct should be easy to modify and accomodate the bigger aperture)

Re: Extruder fan specification ?

I would like to revive this thread.

Is anyone using a 40mm Noctua fan at the moment?

Have there been heating problems? Melted ABS parts near the heatsink?

If yes, can anyone post the link of the adapter they are using? it seems the one from Patrik is not there anymore.

I am using a 40mm Noctua fan with the adapter from GrabCAD.

I was also able to get my hot end up to 410C with no ill effects.

Thank you very much ayourk,

I'm gonna try this !

And thanks to the others for their feedback, you've been very helpful.

Re: Extruder fan specification ?

I read through the entire thread and then tried Mark's version ( https://grabcad.com/library/mk2_40mm_fan_duct-1 ). I thought this one showed the most initial promise, but I found that I could not print the part for a couple reasons:
1. The part needed to be rotated ~119.6 degrees
2. The overhangs didn't work, even with support
I also did not like the holes in the print designed to carry the screws.

Instead I made a few changes:
1. I added tapered pins to hold the near side (now only uses 2 screws.
2. I extruded the inside 40mm screw mounts so the supported the overhang.
3. I (mostly) filled in the overhang.
4. I rotated it so it was ready to print

Now it prints pretty nicely and mounts up. I added the file as an attachment to my comment in the link above.

Re: Extruder fan specification ?

I modified the 30mm to 30mm version.

Re: Extruder fan specification ?

James, you said you attached your updated file to a comment at this link:
https://grabcad.com/library/mk2_40mm_fan_duct-1

I don't see it. Please double check and upload again.

Re: Extruder fan specification ?

James, you said you attached your updated file to a comment at this link:
https://grabcad.com/library/mk2_40mm_fan_duct-1

I don't see it. Please double check and upload again.

I removed it because I modified the wrong version. I modified the 30mm to 30mm version. I requested the 30mm to 40mm STP file so I can make the same changes to that version. Once done, I will upload the correct part.

Re: Extruder fan specification ?

James, you said you attached your updated file to a comment at this link:
https://grabcad.com/library/mk2_40mm_fan_duct-1

I don't see it. Please double check and upload again.

I removed it because I modified the wrong version. I modified the 30mm to 30mm version. I requested the 30mm to 40mm STP file so I can make the same changes to that version. Once done, I will upload the correct part.

Hey guys,
I also got a Noctua fan but reading through this thread now I am not sure it's a safe mod.
James, did you ever get around to uploading your modified version?
The original one does seem hard to print.

Re: Extruder fan specification ?

James, you said you attached your updated file to a comment at this link:
https://grabcad.com/library/mk2_40mm_fan_duct-1

I don't see it. Please double check and upload again.

I removed it because I modified the wrong version. I modified the 30mm to 30mm version. I requested the 30mm to 40mm STP file so I can make the same changes to that version. Once done, I will upload the correct part.

Hey guys,
I also got a Noctua fan but reading through this thread now I am not sure it's a safe mod.
James, did you ever get around to uploading your modified version?
The original one does seem hard to print.

I ended up slicing in Cura and it came out perfect. Make sure it is rotated correctly. I have not installed it yet.