It is tough to just think of this off hand without the parts in front of me. I looked at the breakdown guide for the Mini and will give it a go. Since it sound like fun I'll give my thoughts.
Tools
- Dremel (fairly cheap kits are available which include the dremel bits mentioned)
- cutting drill bit for Dremel
- cutting wheel for Dremel
- grinding and polishing attachments for Dremel
- Power drill with a variety of all purpose bits
- Putty knife (to open mini case)
- an array of philips and torx screwdrivers (the breakdown only mentions a T-10 torx for disassembling the Mini)
- sheet metal shears
Material
- a small piece of sheet metal (preferably a heavy gauge of aluminum since it would be strong enough and much easier to cut and work than steel)
- a small sheet of clear acrylic (or some other sheet plastic this will be replacing the rear port plate)
- Super Glue
- small screws and nuts for the mounting structures
- hard drive screws
- narrow rubber tubing for spacers (like a hose from a fish tank bubbler)
- sand paper and paint (if you do not like the clear acrylic.)
Though it would be a tight fit for the spare Mac Mini case. You could buy two
Acomdata Tango enclosures. Since you are running two hard drives I recommended this due to firewire capabilities. They provide 1394a to SATA. All you really want is the FW to SATA bridge and power cable from these. So I chose the cheapest I could find.
In the Mac Mini I would clear out all internal parts. And cut off the back port plate where it attaches at the base with the cutting wheel, and smoothing it out with the grinding attachments. You will be replacing that back panel with the acrylic panel.
The next part becomes quite tricky.
For the new back panel I would shape the acrylic so that it fits the back groove to the top portion of the Mac Mini's enclosure. It will be glued to that later on.
SATA bridge mounting
For this part I would build a framework for these to mount to using the sheet aluminum. As they will need to withstand the force of cable being plugged and unplugged. This frame would then consist of two base plates for the SATA bridge to attach to. Then two L-shaped pieces to tie the base plates together with the Mac Mini case.
The base plates need to have their sides and front bent. Then you will be able to rivet these plates to the L-shaped pieces and eventually screw them to the acrylic back panel when it is completed and glue in place.
Here is a rough diagram of my idea
I would then temporarily attach the acrylic panel to the back of the Mini's casing with clear tape.
Attach the bridges to your structure now with the nuts and screws. Using small pieces of the tubing as a spacer between the bridges and base plates. Position the bridge on the base so that the ports jut out sufficiently to account for the thickness of the acrylic so that you will not need to make to port holes to large
Now flip over the Mini's case to position your assembly against the Acrylic. Use the felt marker to mark the holes you will need to make the ports accessible and front screw holes for the base plates. Now cut the holes.
Re-attach the acrylic and position the port mounting structure to make sure everything lines up.
Now you can sand and paint the acrylic if desired. I like Krylon Fusion spray paint for plastics. Once dried Super Glue it to the back of the Mini. Wait for the glue to set then position the mounting structure gluing the feet of the L-pieces to the Mini per the diagram and screwing the front of base plate to the acrylic.
To mount the hard drives I would simply make two L-pieces. Drill them to match the hard drives side mounting holes. Attach the hard drives then glue the feet of the L-shaped pieces under the top of the Mini's case. Then attach the SATA and power cables to the bridges.
(If the enclosures where direct connect to the bridges without cables. The mounting structure should still work. You will just need to carefully position everything so the drives line up with your bridge structure.)
Hopefully everything is now done. You can close the case, attach the power cord, and daisy chain the Firewire from your Mini to the two hard drive.
I tried thinking of a way to do this all internally so that you only have a single firewire and power port on the back. However given the extremely cramped conditions of the Mini's you would need to make custom internal Firewire cables which I could not find a supply source for.
Though if you were really brazen you could cut off the fire wire ports from the bridges and use the protruding pins as header pins for standard internal firewire cabling. Then daisy chain the bridges FW ports and have one protruding from the acrylic panel.
For this you would need two 2x5 headers, 20 female terminals from this page
http://www.frontx.com/order_c.html
Then a IEEE 1394 Cable 6Pin Female to 2x5 header on this page
http://www.frontx.com/store/order_a.html
from the same page you will also need a
IEEE 1394 CABLE - 2x5 F to 2x5 F
These cable you would then cut to length crimp on the new terminals then order them correctly in the 2x5 headers.
For power you may need to find a power adapter of the same voltage that came with the enclosures but a higher amperage. Then a port that fits it to attach to the acrylic. From the solder on cables and to power jacks that plug into the internal bridges.
Hopefully that gave you some ideas. Now I sort of want to build one. To bad I don't have much use for external 2.5" hard drives.