i3 Pro B Parts cooling fan

[OverGrownDwarf]

Hi all,
So I got an i3 Pro B for my birthday in November and have been constantly improving it to the point I'm really happy with the prints.
However my last modification before I'll be completely satisfied is to add a parts cooling fan.
While i already have one installed I have not been able to figure out how to make it controllable by gcode. The fan just runs at 100% as soon as the printer is powered on. Whilst I havent had any issues with this causing the first layer not to stick, I would still prefer to have this ability.
Any advice would be appreciated.

[William]

I think you should check the port for cooling fan on the motherboard.
It has only one pwm port.

[GAQ]

Hi OverGrownDwarf,

I am about to add my first fan today... the plugs have arrived in the post !...
I have done much research on the forums about fitting, the most helpful post I've found came from "ppf"

I've copied it for you below.

"... Hi,
here is a way to connect a 2 wires fan to the PWM-FAN connector of the GT2560.

Note : my fan is a brushless DC 12v 0.15A, a very common one.

- the POSITIVE wire of the Fan (in general, it is RED) : connect it to the top pin (nearest of the board edge) of the PWM-FAN port of the GT2560 (with a yellow dot on the GT2560 scheme in documentation)
- the NEGATIVE wire of the Fan (in general, it is BLACK, or another color with a black strip): connect it to the middle pin of the PWM-FAN port of the GT2560 (with a black dot on the GT2560 scheme in documentation)
Note that if you revert them, the fan will not run.

You can control the speed of the fan via the LCD, via REPETIER-HOST buttons/slide, via g-code, or via le slicer config :
- via LCD : menu Control / Temperature / Fan Speed : 0 = Off, 1 to 130 slow speed with 'vibrations' (avoid this range !), 131 to 255 real adjustable higher speed range. The 1 to 130 range 'vibrations' is due to the fact that my 1$ fan is not a 3-pins real PWM fan and it cannot start rotating at low power. Perhaps that this range can be reduced with better quality fans, or real PWM fans.
- via Repetier-Host / Manual Control : with the fan slide : can stop the fan, or turn it on with some minimum speed (also with the low 'vibrating' range) to maximum.
- via g-code : M106 Snnn : nnn=0 for off, 255=max speed (also with the low 'vibrating' range). You can also add this code in the Start G-code when using PLA M106 S255 to cool the layer, and in the End G-code M106 S0 to stop the fan.
- via the Slice config : in Filament Settings / Cooling : a lot of options for a clever setting arround the fan for bridges, small parts, layers, ... etc

Hope it helps. ..."

I hope this helped you !

NB - If you use a standard 3 pin lead, you'll find it fits your board with the yellow wire on the top, black middle and red to the bottom...
I've seen a Geeetech drawing saying this is the way the plug is wired, and I've seen several posts saying that this isn't true (As above) !
( I also have a Geeetech drawing with the label "X min" next to the "Z-Min" plug )

[GAQ]

Hi,
Quick addition to earlier post...
I did a quickie bodge job with just twisted wires to see if ppf was correct...
Ye har !
My El cheapo blower fan works a treat.
Repetier ran it first time without any mods to firmware or anything else.
It will happily start up at 50% and runs flat out at 100% just as it's supposed to.
I reckon I'll do without the slower speeds.
I'm going to solder wires and integrate with the loom from the extruder now.
(I'll have a plug near the extruder such that when this £2 fan fails, I can replace without re-wiring !)
Gerry