Quote Originally Posted by cdl0012 View Post
I've searched the forums but couldn't find the solution to probably a very easy problem.

I printed the active cooling duct from thingiverse, wired up a 40mm 24v fan to the "EXTRA" power that is labeled on the PCB of my Flashforge Creator Pro.

When I set the parameters in Simplify3D for cooling (ie. Layer 1 = 0%, Layer 2 = 100%), the fan does not automatically turn on at layer 2.

However, if I go into the menu options and "Set Cooling Fan" on, it turns on without any issues. Thus the wiring is correct, I just can't get it to automatically turn on during the print.

What am I doing wrong? It has to be something obvious that I'm missing.
It's all down to the GCode you are using. It needs to send an M106 command to the printer when it needs to turn on, ie M106 S250 (where S=speed, 0-255)

Since I use makerware alot (and I mean ALOT) for my flashforge and ctc, there is no way to add the fan command unless you use Proftweak and even that has issues. I ended up doing the following to get around it.

I cut the main fan from the left extruder. From its two wires, I piggy backed 2 female connectors (I use XT60 as i use them alot of R/C stuff)

I then copied this on the other extruder - so there is 4 female connectors above my hotends.. 2 for left and 2 for right.

I put a male connector on the cooling fan and on the left extruder and plugged them back in. So I am running 2 x 24v fans off the one output. So basically, the cooling fan runs whenever the extruder fan runs (and this doesn't seem to load the motherboard up much at all) Did the same for the Right extruder fan.

If I want to switch to the right extruder but have cooling for it, I simply unplug the cooling fan and plug it into the female for the rights fan and vice versa, that way no matter which side you print on, you can have active cooling - and only need one extra fan.