Dashcam forced cooling 40mm fan

Outbacknomad

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Dash Cam
4 x Garmin 56 plus 100Ah auxiliary battery
Garmin 56 with Noctua 40mm x 10mm 12v fan temporarily cable tied to Garmin camera bracket & wiring is temporary for the test. There is some recorded noise but it is an acceptable level. The fan with the resistor to reduce fan speed to quieten it is basically not audible in the car with other noises, and the car itself is pretty quiet.

The air flow is not a lot but I feel it is enough. One could add a heatsink if there is space on a camera to increase surface area. Mounting the fan a touch further away if one is really fanatical and on a rubber isolator. The recorded fan noise is minimal, so not really an issue.

One just needs to make up more presentable bracket if cable ties are not acceptable out of a piece of aluminium or look for something in the hardware store to modify. A good excuse to get out. Or maybe bend up a piece of wire as a bracket. A bit of grey matter exercise required!

These fans are not cheap, but they are very good. This 40mm fan has been running a few 1000 hours for a different purpose. I have used about a 100 of the larger size Noctua fans, 80, 92 and 120 in computers for more than a decade. A few have been running continuously over this period at a reduced speed with their supplied resistor.

A 40mm fan at a reduced speed will be a lot quieter than a 25mm fan at full speed.

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(A linear polarising filter on stepup ring)

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(Spare camera)

A 9MB 1 minute file with Noctua 40mm x 10mm fan running. Compressed video but sound left at a high bit rate.
 
Great DIY!
Have similar idea for years (6-7y.) with fan running from mini-solar "bracket" powering the cooling fan, this way doesn't consume car battery. Still haven't seen any factory-produced solutions, however I do see this idea does have a potential.
 
Since this project came about due to questions that arose from a thread about parking guard on sunny days, I guess the question would be the sound of the fan when parked and the temperature differences of the camera with and without the fan.
 
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Noctura fan.
Also the brand i am using in a mothballed PC project, but their industrial line in 140 mm, those move a lot of air at a reasonable noise, though i will not be running them at full tilt.
 
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fan is likely to be a lot more noticeable when parked, for those where overheating is an issue it could be a worthwhile compromise, that is of course if the fan is enough to overcome the heat problems, certainly two things that would need testing
 
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fan is likely to be a lot more noticeable when parked, for those where overheating is an issue it could be a worthwhile compromise, that is of course if the fan is enough to overcome the heat problems, certainly two things that would need testing

So often lately when you quote me, you state the obvious. Why is that?
 
I agreed with what you said, and added my thoughts, is that a problem?

What's the point in repeatedly repeating my comments and thoughts with essentially redundant posts? Do we really need you to explain to everyone what was already addressed with my questions?
 
Looking at the specs of the Noctua 40mm x 10mm and 20mm thickness fans, the 20mm is the one to go for.

40mm x 20mm:
5000rpm 9.4m³/h 14.9dB(A) 2.26mm H₂O
4400rpm 8.3m³/h 12.2dB(A) 1.75mm H₂O
3700rpm 6.9m³/h 8.5dB(A) 1.23mm H₂O

40mm x 10mm:
4500rpm 8.2m³/h 17.9dB(A) 1.78mm H₂O
3700rpm 6.6m³/h 12.9dB(A) 1.21mm H₂O

I already had the 10mm thick fan. The 20mm at 3700rpm has basically the same pressure but is considerably quieter, 8.5 vs 12.9

Maximum input for both fans is 0.6 watts. So 1.2AH over a 24 hour period. Not something to stress over too much.
 
Noctura fan.
Also the brand i am using in a mothballed PC project, but their industrial line in 140 mm, those move a lot of air at a reasonable noise, though i will not be running them at full tilt.
I replaced the 92mm fan in my Waeco fridge with a 120mm Noctua industrial fan, running it at full speed, with acoustic material around the edge & fridge insulation cover the fan is adequately quiet. Actually it's pretty good!

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normal_IMG_3507.jpg
 
An idea for a universal bracket for fan using cable management hardware.

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(I haven't tidied up screws)
 
An interesting article on the design of Noctua fans:


Someone who has got a touch carried away with 40mm fans but apparently they are surprisingly quiet even though there are so many.
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