Jalapeno fan blade snapped

[julz]

I discovered one of my Jalapenos was running hot. Too hot to touch.

Here's what I found inside:



It looks like the fan somehow hit the heatsink, as you can see a couple of bent fins.

I have no idea how this happened. The unit used to blow air just fine, it didn't make any strange noises while I was around and I haven't dropped it or moved it about - so perhaps it happened during assembly - but the broken blade only just now moved around and jammed up the fan... or maybe the heatsink and fan just moved closer together due to thermal expansion(?)

Keep an eye on your rig temperatures people!

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[dogie]

Multiple cases of this already.

[Photon939]

The fan blades on those are quite fragile and they seem to extend slightly beyond the normal lip of the fan. I trashed the original one and replaced it with a full height 92mm Panaflo ball bearing fan and now it runs without the case. Runs super cool, usually 30C or less.

[tinus42]

Fortunately that looks like a bog standard PC fan so you can easily replace it.

[jimmy3dita]

That's why the fins must be always on the "cage" side of the fan, and not upside-down like BFL is doing.

[dogie]

That's why the fins must be always on the "cage" side of the fan, and not upside-down like BFL is doing.

Yeah its true. The blade array does droop on the bearing when horizontal and 'hanging'. I've had this on my wind tunnel setup, they appear to be fine but then one or two randomly start to droop after the while and scrape the frame below. I guess with a finned heatsink, skim = catastrophic catch and snap.

[jimmy3dita]

I'm quite sure that the "pull" method isn't the best at all: the fan normally pulls air from sides, then pushing it to the center and below the cage, normally the hottest point.

Probably BFL has good reasons for this choice, but I can't figure which ones

[ninjaboon]

How high did the temp go? Over 50 celsius?

[gbx]

Can you get one of those personal Honeywell fan units from Home Depot for like 15 bucks and aim it right in front of it, just to keep it running until you can get a replacement fan?

Might need to break off the rest of the fan blades just to keep it plugged in and the device thinking it's in control of the cooling.

[Photon939]

Can you get one of those personal Honeywell fan units from Home Depot for like 15 bucks and aim it right in front of it, just to keep it running until you can get a replacement fan?

Might need to break off the rest of the fan blades just to keep it plugged in and the device thinking it's in control of the cooling.

I've found that the Jalapeno does not monitor the fan RPM signal. My jalapeno kept mining away even with the fan completely unplugged.

[tinus42]

Can you get one of those personal Honeywell fan units from Home Depot for like 15 bucks and aim it right in front of it, just to keep it running until you can get a replacement fan?

Might need to break off the rest of the fan blades just to keep it plugged in and the device thinking it's in control of the cooling.

I've found that the Jalapeno does not monitor the fan RPM signal. My jalapeno kept mining away even with the fan completely unplugged.

Great. Crappy hardware design. Better put a fire extinguisher on standbye! 

[ninjaboon]

Can you get one of those personal Honeywell fan units from Home Depot for like 15 bucks and aim it right in front of it, just to keep it running until you can get a replacement fan?

Might need to break off the rest of the fan blades just to keep it plugged in and the device thinking it's in control of the cooling.

I've found that the Jalapeno does not monitor the fan RPM signal. My jalapeno kept mining away even with the fan completely unplugged.

sounds like a fire risk.

[julz]

How high did the temp go? Over 50 celsius?

Undoubtedly - though I don't know exactly. It was so hot I was in a hurry to turn it off.
It was doing about 5.2Gh/s just before I discovered the problem.
Now that it's up and running with a new fan its doing about 5.7Gh/s - which seems about right.

The fan was clearly not spinning at the end.  There was a burnt-looking IC inside the fan motor.