R2 Improved Fan Duct

That fan doesn't do a great job of cooling one hotend, so it's rather ambitious to think it could handle two.

 

Does this help stop the annoying back pressure whistle on the extruder fan?

 

The whistle comes from a shoddy fan/bearing, not backpressure. Have to put a drop of oil in mine once in a while, a complete replacement would be more appropriate but couldn't bother yet.

 

Guess I was too tired the other night, the 2 back screws actually go in the middle holes so aren't length restricted, 8mm screws work fine.
For the front ones I cheated with a nut and washer.

Even found some magnets, it doesn't look hacked




Unfortunately I don't really know what to print that I have a reference of to see if there's a notable improvement.

 

I'm getting curling on the roof of my benchies and a fair bit of pillowing on prints with flat tops (such as the calibration cube). If you're seeing the same, these should be good test cases for improved cooling.

 

I launched a Marvin since it has some overhangs, but never made one before for comparison.

Benchy was pretty nice, but I printed it smaller and I don't remember at what scale. Need to see if I can find it again and measure to use the same and compare. But then I also changed slicer since, and just S3D will have some significant impact...
Never had pillowing, but then I'm using 3 top layers.

 

Has anyone had issues with the part cooling fans working to good with the new fan duct? I have had to reduce mine to 40% to keep them from cooling the hot end down from 210 to 180 as soon as they turn on for the 2nd layer.

 

I'm not that much of an expert here, but that doesn't sound like they're working too well; it sounds like they're pointing at the wrong place. The airflow should be going just below the nozzle, which shouldn't cool the hotend.

 

Could it be ground effect, though? Maybe just turn off/down the part fan(s) for the first n layers.

Use a smoking match to see where the air's going. It's (kind of) what we do for validating cleanroom air flow.

 

I just wanted to add that a naked heat block like this can really take a hit from direct airflow. I can take one of my FF machines and remove the silicone sock and get a thermal error with the stock cooling fan. While it is fine with the sock on for 3-4 day prints+.

 

I emailed Braydon and Jerry and said nice things, so maybe they will share the step file.

 

They sent me the step file to the little fan shroud they made. This one is screw mounted and does look different to the one posted in the other thread.

I sent them a picture of the part we are after, I probably did not word my email carefully enough. Or since they could be mass producing the new shroud they might not give us the step. Worth asking.

Edit: Jason says they are still testing, he will pass us the file once they are happy with the results.