I've been searching for a while now, and I can't seem to find anything. On a case with three 3.5" (unused) floppy bays, would there be a way to mount a fan there in place of the blank plate bezel? They are empty right now with no floppy or hard drives mounted, and it will stay that way.
I did this once with zip ties. The case I had, some coolermaster, it was all meshed vents anyway so I didn't have to do anything special.
A couple options
- Cut a hole through the old bay covers and screw the fan to them (if the covers are solid)
- Screw/tie the fan to bay covers (if the covers are mesh)
- 3D print an adapter
Option 3 would probably look the nicest.
With any option though you're probably not going to get anything larger than an 80mm fan in there, so you're not going to get much air from it anyways.
I did something like what you are planning to my 5-1/4" bays.
First I drilled random holes in the bay covers (I didn't want a grid pattern for the holes).
Then I glued screen 'dust filters' to the back of the covers.
Finally I mounted a 120mm fan at the back of the drive bays, near the top of the motherboard.
My main point is:
Think about mounting the fan near the motherboard side of the drive bays, not near the front of the case.