burning out fans ?

[kristen 0]

I've burnt through a number of fans on the hot end so far and the one cooling the PCB sounds like it's bearing is starting to go as well. The ultimaker has only been together for 3 months so far and typically the fans in my pc's last 5+ years. Any idea if this is tied to the UM board and consequently the fans being run at 19V ? I was thinking of adding an70 ohm resistor in-line with the fan to drop the voltage down to 12V, but Daid didn't seem to think that would work due to the pwm control.

Thanks

[owen 19]

I don't think your problem is common. I think you've been unlucky. If you don't change fan speed during your print you could put code in your GCode header to make it run slower. M106 S255 = full speed. M106 S128 = half speed etc.

 

[cora111 0]

The radial fan for the pcb is crap. Throw it away and get some standard 50 oder 60 mm PC fans. Then the UM is MUCH quieter.

 

[billdempsey 0]

My PCB fan has been getting progressively louder, so I expect I'll be replacing it in the not-to-distant future. I already replaced the fan on the print head with a quieter, higher air flow fan. I only run it at 50% and it pushes about twice the air that the old one did at 100%. I imagine I'll do the same sort of upgrade when I replace the PCB fan. The ones they're using are bottom of the line junk. Seems a bit odd to put a $2.50 fan on a $2300 printer. *shrug*

I'm also considering making an EMF shield enclosure out of sheet aluminum to put over the entire PCB with a better fan built into the shield. From all the trouble I've had with the electronics, I want to block out any potential interference.

 

[bomark 0]

I was looking for replacement PCB fans online and found one i recognize on dealextreme: http://dx.com/p/av-752512s-dc-12v-brushless-cooling-fan-for-diy-128160

Guess I'll keep looking.

 

[albert 2]

The fans start to get noisy after a short while. I peeled the sticker off the bottom fan and put a very small amount of grease directly onto the axis of the fan. Since then, no noise, no problem. I will soon try the same one the hot end fan, this also starts to sound like an old motor from the Fifties.

[billdempsey 0]

The fans start to get noisy after a short while. I peeled the sticker off the bottom fan and put a very small amount of grease directly onto the axis of the fan. Since then, no noise, no problem. I will soon try the same one the hot end fan, this also starts to sound like an old motor from the Fifties.

 

Great idea! Did you use a fine machine lubricant or actual grease? With the speed those mouse motors run at, I would think machine oil, right?

 

[kristen 0]

The fan's I've opened up just have a dab of grease in them. There aren't any seals to speak of, so I don't think the machine oil would stay in place very long. Just about anything will do.

 

[calinb 11]

I've been using this fan from Fry's for a few months:

http://www.frys.com/product/4722209?site=sr:SEARCH:MAIN_RSLT_PG

It's actually 160 mA (see the photo of the packaging lower in the page) vs. the 100 mA consumption of the original fan and the air flow is noticeably more powerful too. I often run with a bubble wrap "tent" around my UM and achieve temps of up to 70 C at fan level, to no detriment so far. It's still as quiet as it was the day I installed it.

 

[calinb 11]

The fan's I've opened up just have a dab of grease in them. There aren't any seals to speak of, so I don't think the machine oil would stay in place very long. Just about anything will do.

 

You might try a thickening oil like this one: http://www.corrosionx.com/corrosionx-heavy-duty.html

I love the entire Corrosion-X product line, BTW (but have no financial interest in it).