IIcx: PSU Fan Bracket replacement

Addicted

Well-known member
Idle hands while awaiting the next delivery of restoration electronic parts...

Both of my Mac IIcx power supplies came with broken fan brackets - missing one of the major retainer clips, or the lesser snaps that keep it flush with the bottom of the enclosure have lost their heads. Just brittle, aged plastic. I made hokey "solutions" using epoxies and silicone caulk.. but they weren't going to last, and were a little ugly, plus I had some "free" time... 🤔

It's the most detailed 3D print creation I have undertaken. I'm happy just having gotten it to work, and the model is fairly flexible (I can tweak a dimension without breaking the resulting body). A Fusion 360 learning experience. Almost nailed it! This morning's print actually fits, but it's just one tweak away from "fine" .. so I will adjust one wayward snap post by a millimeter and re-print.

If others could use this, let me know if there's a common archive for such things and I'll upload the STL.

Attached: build view, model view, comparison photo original with damage (L) vs. beta of the replacement (R).

Screenshot 2025-05-18 at 08.48.54.png Screenshot 2025-05-18 at 08.55.25.png IMG_5521.jpg
 

volvo242gt

Well-known member
Looks cool. That said, unless you want the machine to be 100% original, the IIvx, Centris/Quadra 650, and 7100 power supply works perfectly in a IIcx, IIci, or Quadra 700. Does away with the fan support bracket, since the fan is mounted inside the PSU enclosure.
 

Addicted

Well-known member
@volvo242gt - are those PSUs different than the IIcx? Sorry if I was too brief (I generally say too much...); this bracket is part of the PSU; is the same bracket within the 650/7100/IIvx ?

The beta replacement partially installed, with a generic NMB 12V fan:
IMG_5522.jpeg
 

volvo242gt

Well-known member
@volvo242gt - are those PSUs different than the IIcx? Sorry if I was too brief (I generally say too much...); this bracket is part of the PSU; is the same bracket within the 650/7100/IIvx ?

The beta replacement partially installed, with a generic NMB 12V fan:
View attachment 86846
Yep. Same case size, a little more power, since it sometimes was powering a CD-ROM drive, in addition to the floppy, hard drive, and board itself.
 

volvo242gt

Well-known member
*slight correction* The fan is mounted differently inside the later power supply, so it doesn't use the bracket that slides down into place. Instead, the top case panel covers the fan.
 
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