Since adding the amplifier and car speaker into R2, I have noticed its getting a little warm inside. R2's Asus Netbook sits on top of the amplifier and also generates a fair amount of heat on its own.
I debated a few potential locations to get some air flow going but some of the first thoughts were impractical. The location would block access to something.
Then the obvious appeared....R2 already has two vents, why not use them to draw in cool air? The dome top has a dime-sized opening. I was going to cover it but liked that there was a place for heat to escape.
My local electronics store, ICC North, had many 12 volt fans to choose from. I went with a 4 inch x 4 inch fan rated for 32 cubic feet per minute. Testing it out, it didn't seem to terribly loud. I also have a 2.5 inch x 2.5 inch cpu fan...but I really like that the larger one fits over the entire upper vent.
Using some stock aluminum material, I essentially used some 2 inch long 4-40 thread screws to thread the fan into the bracket. The frame piece that goes down one side of my vents has threaded holes in the back (the newer JAG v5/COM-8 have these too). I added some thin rubber washers to address any vibration issues and threaded the assembly into the back of the vents....
I'm testing this on my newer frame as R2 is at my office.
This will direct a lot of airflow directly over the amplifier and netbook, allowing the heat to flow up and out the dome.
We'll see how well my little prototype works in my functional R2 tomorrow.