[q] extruder fan flow direction?

[Gregory Sullivan]

In oem extruder setup does the fan blow or pull on the heatsink...?

Thanks

[Clinton Hoines]

It blows across the heatsink

[Gregory Sullivan]

Thank yo

[Gregory Sullivan]

Thank you....

[Big-E]

Actually, On my Rep2, the fan blows away from the heatsink, it has from day 1; never caused a single problem.

The decal on the fan should be facing out.

In all honesty, it shouldn't matter which way it faces, so long as air is circulating across the heatsink. logically speaking, sucking air through the heatsink fins makes more sense, as it's drawing heat away from the heatsink.

All I know is my machine came that way, and I haven't changed it.

On Thursday, December 5, 2013 5:58:48 AM UTC-6, Gregory Sullivan wrote:

Thank you....

[Gregory Sullivan]

Thanks again

[Jetguy]

Blades facing fins =extra noise at a minimum.

So sure, it might work and that might be how it shipped but that is not as common a configuration and the generally agreed on way is blowing into the heatsink.

[yournam...@yahoo.com]

I have heard several prefer to have them pulling air rather than pushing to help avoid blowing any air onto the part which could help with warping or adhesion issues. I personally don't care either way.

[Eighty]

The fan should always blow into the heatsink. Fans aren't nearly as efficient when pulling air.
Here's a real-world example. Take a regular box fan and block the airflow on the outlet side. You'll get forced air, albeit at a reduced rate. Now go to the back and block the inlet side. That fan won't move any air at all.
Same goes with the heatsink fan to a lesser degree. The fan needs to compress air into the fins. It won't work as well if you're trying to suck air out of the fins. Most of the airflow would come from the surrounding area (not the fins), leaving the middle of the fins with little to no flow.

[billyd60]

You're only thinking about that one way. There is also more turbulence on the push side of the fan and also more turbulence through the fins when air is pushed through them reducing the effectiveness of the cooling flow.

I used to design electronics enclosures for a large aerospace firm, and we always removed air from the enclosures, rather than pushing air in, unless we had no choice.

Also, the supplied fan on the r2 installs easier and better, when the fan is blowing out, because of the location of the wires, and the mounting holes on the fan and shroud allow the screws to be firmly tightened without deforming the casing. When flipped around the install is much more awkward and it's easy to over-compress the fan housing with the mounting screws.

I've had it on both ways and there is no functional difference in the extruder temps or output of the printer.