Downward cooling... really?

[Andy Cohen]

In my opinion using the two extruder box fans for downward cooling is not a good thing. Not at all. Why not?

1. You need to be able to turn them down or lower their speed for some filaments

2. You do not want the cooling to the extruders to be diminished at all

3. Taping over the duct is NOT an appropriate approach. 

4. Box fans do not provide enough downward cooling for the level of control on the molten plastic an experienced operator will need

I would like to add a radial fan to the back of the block that rides the rails and I'd add a shaped duct to direct a controllable blast of air to areas around the extrusion/fusion areas. Designing replacement cowlings for the current box fans to direct their blow to the extruders would be easy. Since the N2 is a Rumba board I would assume there's a place on it for a downward fan and that it be controllable via gcode. Is this possible? Can we get a bit of info about where on the board? How to get to the board? Voltage?

[Andy Cohen]

That is a slick design.

On Friday, February 5, 2016 at 3:29:54 PM UTC-8, Jetguy wrote:

FYI, the board at the head has extra Gcode controlled fan output.

My vote is one or two of these. https://www.digikey.com/product-detail/en/BFB0312HA-A/603-1112-ND/1014443
Hint, same fan SeeMeCNC uses for print cooling on their Delta printers.
Same fan I used on Fredinni's Core XY.


Yes, they are $12 each.
Yes, worth EVERY penny
Yes, the fan outputs are 12V thanks to the built in 12V regulator on the motion control board.
Yes, as far as I know, normal M106 S255 and M107 turn on and off the fan output and it is PWM.

These are very quiet, very light, reasonably powerful, double ball bearing last forever kind of fans.
I also bought these 35mm thicker fans with higher CFM before i got my printer (in the process of installing them) to better cool the cold end of the extruders https://www.digikey.com/product-detail/en/ASB03512HB-F00/603-1722-ND/3444176

[Derek@Raise3D]

We are working on V2 hotend right now. After that, we will move onto new cooling system. Still takes some time.

在 2016年2月6日星期六 UTC+8上午9:18:52，Andy Cohen写道：

[阿俊]

I have got myself a 0.5A 12V 40mm fan and it was an overkill that even stopped the alum block from being heated up despite all the possible tape shielding (apart from the fan noise as loud as a operating hairblower)

Now I have a slicker 40mm fan and it's working great.

[Andy Cohen]

The air should be pointed to the areas around the fusion spot not on it and not on the block. The flow needs to be quite focused and not wide angle. This was one thing MBI did correct in the Rep2 and in the Gen5s, although they made speed control impossible. I ordered the fan Jetguy suggested. i really like the low profile. I design dieting for it.

[Derek@Raise3D]

You hacks are welcomed! :D

在 2016年2月7日星期日 UTC+8上午7:15:02，Andy Cohen写道：