Got my fan installed only to realize that the third wire is a tachometer not a pwm input. Buyer beware on ebay I guess
Isn’t that always what the third wire on 12v computer fans is?
Yeah, apparently I overlooked the obvious. Derp
There are fans with 4 wires, they have the tach output and pwm input.
@Jeff_Karpinski you tha man bros, you are correct
I really suggest you print some kind of shroud or cover so the fan doesn’t cool your hotend.
@Eric_Moy Is that 3 bowden tubes?
@Tim_Rastall with the important question. Triple extruder?
could be or he just put them there to fool us
@Jeff_Karpinski
Isn’t that what @Stephanie_A basically said?
no
i meant the tubes. he put them there for the pic to make it look like he has a better 3d printer
@zephyrin_JG I replied to @Jeff_Karpinski
@Tim_Rastall 1 Bowden tube, 1 rube with wires, only 2 tubes. I clipped the top so you see 4 legs. I think I only have enough patience for one extruder right now
I needed the MOSFET to be in the fan because I’m driving it from a pwm pin on the Sanguinololu, so it’s only TTL input.
@Shachar_Weis I wish I would have read that before my print last night. Without a shroud and pwm, my hotend quickly dropped temp. Luckily I was watching the print and noticed filament was not extruding. The nozzle temp dropped to 50 and the filament got all bound up in my extruder. It ended up moving the extruder gear, so I need to retighten… Or maybe I need to just bit the bullet and finally finish my minimalist extruder upgrade.
I’m going to try a lower speed on a true pwm fan so I can print a decent shroud. The print quality is so much better with a fan. Without it, I don’t have faith I can print adequate screw holes. Although I can always use the makerbot at work as a last resort
@Jeff_Karpinski actually the brown wire is generally for pwm input on the 4 wire fans. I didn’t want to make a MOSFET driver so I’m opting for a pwm control fan. I did find one laying around today, but the darn thing still spins at 0 duty cycle. I should probably keep looking as I want to be able to shut it off
Again, I should probably expand more before hitting send. I have a sang board so I don’t have a fan output. I’m using a pwm output pin but it’s only TTL. I can make/buy a MOSFET driver to pwm the 12vdc from the board’s pwm output, but I’m opting for the simpler method of using a fan that accepts TTL level pwm. Yet another reason that the sang board is not suited for upgrades. And yes, so true about wire color. I’ll leave by calling it the fan control input line
Yeah, apparently this is one of them, the 5vdc and 24 vdc versions do go to 0rpm. Figured that was the reason
@Jeff_Karpinski
Yeah… it’s power. Power goes in. So it’s input. It’s a wire so it’s an input wire. PWM is on it, so it’s a PWM input wire. And it’s one of four where the other three can be understood as stable VCC, ground and tacho output. It’s what @Stephanie_A said. Just a matter of definition…