Hi I haven’t got one yet, but looking at the heat-trapping structure formed by any pi-hat, I worry a bit about cooling. Pi4 needs a fan even without a hat, and as the hat likely obstructs airflow, fan support seems to become more urgent.
Q:
Location: Where do I put that fan? Do I potentially need a new case? Does yours have space for it?
Power: Do I still have a GPIO pin left to power the fan? If not, is there an alternative way to power it?
Thanks
Arjan
Check @rbn’s post here: PiSound with Raspberry Pi 4 - at the moment we don’t have an official guidance on how to go about cooling, but rbn’s solution may work.
A slightly modified pimoroni heatsink case might be a step in the right direction?
Aside from a booster-header, i used 40mm M3 bolts instead of the default M2.5. so i carefully widened the holes in the PI, drilled through the heatsink-case-top (very close to the heatsink edges), and widened the original middle case-standoffs. The pisound itself and topcover are untouched.
Is heat really a problem?
@wxslo do have a kind of technical drawing for the top and bottom of your “open case”?
Thanks in advance.
Heat all depends on what is running on the Pi. I measured 73°C running pimiga in the standard pisound case 
Sry no drawing, i just drilled through the existing 4 holes in the heatsink-case-top. Low rpm, aluminium is quite soft, maybe first with a 2.5mm drill. The 2 holes next to the gpio pins are a bit too close to the edge, it just about works as long as you drill straight.
The heatsink-case-bottom is unchanged (holes are already M3).
hth.
Oh, quite hot!!
About the drawing, I meant the top and bottom acrylic (?) plates.
the top acrylic is the original pisound case top, as-is with original mounting. That’s the only acrylic in this setup.
