Extruder fan specification ?  

Re: Extruder fan specification ?

Just a notice. Brushless fans contain electronics to make it turn. It will most likely die when too high voltage is applied. Be careful when using 5V fan on higher voltage.

True, maybe 5.5V should be the upper limit.

This is definitely highly experimental and if the fan fails during a print....

Just looking for solutions, that's all. 🙂

Re: Extruder fan specification ?

No, I'm the worst one when it comes to electronics! So I shouldn't experiment probably, hehe
But..whats the worst thing that can happen, a small fire 😀

Re: Extruder fan specification ?

No, I'm the worst one when it comes to electronics! So I shouldn't experiment probably, hehe
But..whats the worst thing that can happen, a small fire 😀
Maybe not even that. You may lose HE cooling from failed fan, it most likely leads to clogged extruder, not fire.

Re: Extruder fan specification ?

No, I'm the worst one when it comes to electronics! So I shouldn't experiment probably, hehe
But..whats the worst thing that can happen, a small fire 😀
Maybe not even that. You may lose HE cooling from failed fan, it most likely leads to clogged extruder, not fire.

Clogged extruder at the least. Melted x-carriage possible as well depending on how much time elapses before it's caught.

Hmm. Maybe I can reach out to Noctua and ask them what the hard upper bounds are on the part.

Re: Extruder fan specification ?

Patrik could always use M42 P8 S255 to turn the extruder fan on at full speed, and M42 P8 S0 to turn the extruder fan off.

You can let the 5V fan run for a bit at these amounts or find a lower S value that works better and then adjust the firmware for that value.

Re: Extruder fan specification ?

I did this mod too, using fantastic compact adapter made by christian.v2 (thanks!) - now it is actually possible to be in the same room with the device when printing!

Some cooling time measurements (this is with E3D sock in place) from 215 to 50 degrees (when the fan shuts down)

1. Stock E3D fan: 8:10
2. Noctua fan: 9:46
3. And (maybe the most important metric), fan disabled: 14:53

So E3D fan decreases cooling time vs no fan by 6:43. Noctua (403s) on the other fan results with 5:07 (307s) improvement.
This means that Noctua fan provides very roughly 75% of cooling performance of original E3D fan - this is more than good enough for me.
There might be some more subtleties involved of course (possibly some additional negative effects caused by much lower static pressure on Noctua), but so far everything looks OK.

By the way, I did not use 'low nosie adaptor' with Noctua, the fan is already silent and I did not want to impact cooling performance further.
It is also beneficial to perform PID autotune routine after changing the fan, as he thermal response of the entire system is now visibly different.

Re: Extruder fan specification ?

I have been looking at fans based on the specs listed in earlier posts. I know one of you dislike sunon, but I tried one of their 30mm fans and it easily cut the noise in half, as in it sounds like a small fan, instead of a hair dryer.

The fan is Sunon MC30101V2-000U-A99, purchased from digikey.com for $10.50 (which is cheaper than the noctura 40mm fan). The airflow is 4.6 CFM, and static pressure is 3.05 mm/H20 (.120 in/H20).

To try and keep inline with the data that is already in the other posts:

Stock E3D fan (Xinyujie Electronics XYJ12B3010H) time from 215 degrees C to 50 degrees C was 6:30, room temp was 25.5 degrees C.
Sunon MC30101V2-000U-A99 fan time from 215 degrees C to 50 degrees C was 7:22, room temp was 26.2 degrees C.

The datasheet for the Sunon MC30101V2-000U-A99 lists noise at 20 dBA, while the datasheet for the Noctura 40mm fan is 17.9 dBA.

I also ordered the Noctura 40mm fan, so I can do a side by side comparison between the Sunon fan and the Noctura, which I'm sure is quiter, but is it so quiet as to warrant adding a bulky looking adapter to my printer? I'll report back once the 40mm fan arrives.

Re: Extruder fan specification ?

Just a quick note.

I think I found the paradise on earth for fan search, it's here: http://www.digikey.com/product-search/en/fans-thermal-management/dc-fans/1179730

Re: Extruder fan specification ?

Yep, and their warehouse is only a few hours from me so I get parts really fast 🙂

I will admit their site can leave a lot to be desired when you aren't quite sure of the exact thing you want, I often go to mouser.com as their search and browsing is easier, then compare prices using the manufacturer's part numbers between the two sites.

In this case digikey.com has A LOT more fans to pick from, at least in the smaller sizes.

Re: Extruder fan specification ?

I managed to destroy the 30mm fan while I was dismantling the extruder during it cool-down phase. My own stupidity, but I think a protective grill in front of the spinning blades would help.

I've ordered a 40mm Noctura fan and will print the adapter/s when I have a new standard 30mm fan installed. Looks like Jaycar have a similar 30mm fan in stock. I might even buy a 40mm fan while I'm there.

I 'll also get some connectors so that the fan gets plugged in at the hot-end. I like to leave the Rambo alone when I can.

Re: Extruder fan specification ?

I managed to destroy the 30mm fan while I was dismantling the extruder during it cool-down phase. My own stupidity, but I think a protective grill in front of the spinning blades would help.

I've ordered a 40mm Noctura fan and will print the adapter/s when I have a new standard 30mm fan installed. Looks like Jaycar have a similar 30mm fan in stock. I might even buy a 40mm fan while I'm there.

I 'll also get some connectors so that the fan gets plugged in at the hot-end. I like to leave the Rambo alone when I can.

I am pretty sure that the 30mm fan is direct from e3d-online.com.

Re: Extruder fan specification ?

I am pretty sure that the 30mm fan is direct from e3d-online.com.

I might have to order one just in case other options don't work out.

The fan I bought from Jaycar today is too weak, but much quieter.
https://www.jaycar.com.au/30mm-thin-12vdc-2-wire-fan/p/YX2501

It has about 1/3rd of the airflow of the original fan, I guess it might be enough in some circumstances, but probably not in a hot enclosure.
Considering that the original fan keeps things in order even when the cooling air is 50 or 60degC in the enclosure, or possibly significantly higher with a bed temp of 100degC, I figure that there is a large safety margin when the cooling air is much cooler.

I want to test this weak little fan, and I want to set it up as repeatable as I can.

I think we need some test procedures that are easy and relatively repeatable, so we can compare fan performance without clogging the extruder. I know others have reported some tests earlier in this thread, but I cannot find it right now.

My suggestion for testing fans that are possibly to weak:
A) Have something like polycarbonate in the extruder from the last print (so it will not melt at all).
B) Move the hot-end as high on the z axis as it goes, into the middle of the x-axis, and move the build plate into the middle.
C) Dial up the 'Preheat PLA' option and heat the hot-end to 215degC.
D) Then turn off the heat bed: Push > Settings>Temperature>Bed>set to zero.
E) Then select >Preheat>Cooldown> and note the time it takes to cool from 215 degC to 50degC.
F) Note the ambient air temperature and interpret results in relation to ambient temperature.

As a stress-test for a fan expected to be good, place the extruder in the middle of the hotbed just above the bed, and heat it to 100degC, maybe even with enclosure closed around it.

Re: Extruder fan specification ?

Maybe the fan is not so bad, here the first test result:

Test one Jaycar YX2501 fan: Start cooldown at 21:35hrs from 215degC:
Ambient temp: 26.1degC in bottom half of enclosure, no top half.
0min: 215degC

1 164
2 125
3 96
4 76
5 62
6 51
6min12s: 50degc

It shows how much more effective the cooling is at higher temperatures.

I need to find the other tests the others have done here to compare.

Looking at this, I think problems with clogging extruders due to insufficient fan cooling would most likely occur with PLA, or other low-temperature filaments, and when the ambient air temperature is high.

Re: Extruder fan specification ?

I found Davids test:
Test done. Test conditions:

Both printers preheated to PLA (210/55), extruders homed and moved to X=10, Y=200, Z=50. Both printers in the same room, room temperature 23°C. Heaters turned off on both printers at the same time. Measured time until hotend fan went off.

Original fan extruder cooled down in 6m46s. Noctua fan extruder was at 69°C at the same moment.

Noctua fan extruder cooled down in 9m12s.

My little Jaycar fan compares quite well so far! 😀 Maybe my printer is still in business.

I have tweaked the procedure a little bit to make it more real-world like. Instead of selecting 'cooldown', I selectively turn down the extruder temperature to zero, while the bed stay on. I aborted a print after the auto calibration and the z-axis somehow ended up at Z 15.34 and it is not available to be changed in the settings. So, Z 15.34 it is.

Test 3 Jaycar YX2501 fan: Start nozzle cooldown at 2016-11-06, 2218Hrs:
Ambient temp: 26.6 degC in bottom half of enclosure, no top half.
Extruder temperature: 215
Bed temperature: 55
Extruder position: Z15.43 Centred over bed
Bed position: Centred
Temp at minute:
0 215/55
1 165/55
2 125/55
3 97/55
4 78/55
5 64/55
6 54/55
6:30 50/55
The cooling slows down just a little towards the end, due to the ongoing heating of the bed to 55degC.
Next up: Testing with bed temp 100degC.

Re: Extruder fan specification ?

Test 4 Jaycar YX2501 fan: Start nozzle cooldown at 2016-11-06, 2238hrs:
Ambient temp: 26.4 degC in bottom half of enclosure, no top half.
Extruder temperature: 215
Bed temperature: 100
Extruder position: Z15.43 Centred over bed
Bed position: Centred
Temp at minute:
0 215/100
1 167/100
2 128/100
3 101/100
4 82/100
5 67/100
6 58/100
7 52/100
7:19 50/100

Comparing these results and thinking about them, it becomes clearer that the temperature reduction at high temperatures is less dependent on bed temperature.
I think the results in the first minute or so should also be less influenced by the ambient temperature.

Overall, I conclude that the last 2/3rd of the above tests are not very useful, and that a more efficient routine could be to measure the time that it takes for the extruder temperature to drop to 150degC.

May be someone with several different fans could run a little test series to show if a shorter, high temperature cutoff test will distinguish between fans better than the full test down to 50degC?

Re: Extruder fan specification ?

I should be getting a 30x30x10 fan rated 5 cfm on monday, so while i was messing around with new bearings today, i also I timed cooldown time of my stock fan today. Unfortunately, i used preheat to PLA starting at 215°C irc and didnt start timing at 200°C, but maybe it's still of use to somebody:

Original fan:
After 1 minute 18 seconds reached 150°C
after 2:37 (total) it reached 100°C
and finally after 5:20 it reached 50°C

...

Allright, here are the results.
One printer, the same noctua fan, the same initial conditions, I only changed fan adapters. Both adapters were printed from orange PETG and the same print settings (0.2mm layer, 2 shells, 10% infill).

Patrik's adapter cooldown time: 9m12s
Aaron's adapter cooldown time: 8m55s

My evaluation/comparison:

Aaron's adapter cools a bit (3%) better. The difference is probably caused by a bit cleaner air path (no cutouts for screws inside). Aaron's adapter also provides much better fit at fan side and it seems to me that also angle of the fan is slightly better.
On the other hand, Patrik's adapter provides much much much better fit at extruder side. To be honest, Aaron's adapter doesn't satisfy me at all when talking about mounting to extruder. It keeps falling apart when extruder does rapid movement changes. Maybe if mounting pins were a bit larger...., but I wouldn't trust them anyway.

Re: Extruder fan specification ?

Christian's adapter cooldown time is 9m19s. Almost the same result as Patrik (only few seconds worse), but mechanical design is the best so far (for me).

Re: Extruder fan specification ?

Thanks a lot for your contribution to the community 🙂

However I think I will try to find a stronger fan, I do not feel comfortable having a fan that is cooling with an important difference time from the stock one, even if it seems ok in your case.

Please shout out if you find a better one! I'm still not ready to give up this quietness 😀 (Currently negotiating a second printer with the wifey, the low noise level really helps lol)

Well, I'm going to try out the one bigger Noctura size, using it with the ultra quiet adapter. If it does not cause trouble due to too much mass slowing down to extruder carriage, then it should be silent compared to the rest of the printer, and match or exceed the original fans performance.

http://noctua.at/en/products/fan/nf-a6x25-flx/specification

Re: Extruder fan specification ?

I'll throw another design for an adapter into the mix. I'm not sure I'll be using a 40mm fan, but I'm going to test some before I make my final decision. It seems the noise of the fan has a lot to do with obstructions in front of the fan as much as anything else. If you take the stock fan off and just let it run in the air it is not very loud. Still not as quiet as the Sunon 30mm fan, or the Noctua 40mm fan, but much quieter compared to when it is installed. I would like to see this effect on some other fans to see what the installed noise is compared to the advertised noise.

I added a divider in the adapter to split the flow, as going around a curve will force the majority of the air to try and flow around the back side of the hot end, and do minimal cooling on the front side. I have no idea if this is actually true, just a thought, as the back pressure of the air trying to go around the back side may balance it out and force more around the front side, assuming it doesn't equal the static pressure of the fan, in which case airflow will more or less stop.

Adapter file: https://grabcad.com/library/mk2_40mm_fan_duct-1

Re: Extruder fan specification ?

Hi,

I do not know how to say it but I am really impressed by your modelisation of the full printer !! It's really cool to have this model when you want to try some mod of the printer ! High five for that !

Regarding the fan duct it seems a good idea to me, but only the infamous cooldown test will give a verdict regarding efficiency 😉