Change a Commodore 1541 Into a RAID Server

Need a quiet, energy-conserving storage and print server? Here, I describe how to stuff one, the Thecus N2100, into a vintage external floppy casing, the Commodore 1541.

In our flat, we have several laptops, some of them running MacOS, and a PC, and so we wanted to have a central storage solution (what is called a NAS: network attached storage). We chose the Thecus N2100, because it is one of the cheapest RAID devices, runs Linux and people seem to be happy with it. But when we realized how noisy the little bugger turned out, I decided that it would need to go into a new case.

Here, I describe a rather simple case mod. Almost no tools and only a little soldering required. As a result, you get a very compact and super-silent home-server.

The main components needed are obviously the Commodore 1541, the Thecus N2100 and a couple of harddisks.

For those of you who grew up on a Commodore 64 home computer, there will be no need to explain what the 1541 is: a beautiful external disk drive, made for slightly floppy disks that measured 5.25 inches. You can get them very cheaply at ebay. Or you might have still sit one around.

The Thecus N2100 is also called "Yesbox" by its manufacturer and rebranded by several importers, for instance Allnet in Germany. It has about the same height and half the length of the 1541, comes in a cheap metallic PVC box and makes a lot of noise with its tiny fan. Currently, it sells for about 250-300$ without drives. That's a lot of dough, but still cheaper than the RAID competition.

The N2100 runs on its custom brand of Linux (you may also install Debian). It offers two independent Gigabit Ethernet networks and can take two SATA drives. If you get two 500GB drives, you get a terabyte of space - or half a terabyte in a secure RAID configuration. (I bought two Samsung Spinpoint drives at less than 100$ each.)

You will need few additional parts:
- A couple of harddrive enclosures, such as the Scythe Quiet drive. These are optional (and as it turns out, may be very difficult to fit), but the reduce the noise of the operating harddisks significantly, and they also dissipate the heat much better than the naked drive alone.
- SATA and power extensions (from male to female). These turned out difficult to come by in Germany (I have seen an American vendor of these, though). Fortunately, they come with the "Scythe Quiet drive", and for one which was too short, I have salvaged a SATA extension backplane (about 5$ in your local computer store).
- A push switch to turn the thing on. I have bought a blackish round button that fit through the hole of the floppy latch (about 4mm).
- A few bits of stiff packing foam to cushion the drives against the casing and each other.

Tools:
We will need to cut a bit of metal and PVC. Also, we will have to solder a couple of wires. And hot-glue helps enormously. (I had it all done, very unprofessionally, on the kitchen table in little time, and I am a pretty unexperienced tinkerer.)

The N2100 offers the following features:
- 2 Ethernet connectors
- 2 back USB
- 2 front USB (only one visible)
- lots of fancy blue and blue/red LEDs
- 3 buttons: On, Reset, and Upload (the latter automatically uploads the contents of a USB medium from the visible front USB)
- optionally: WiFi connection (there is a socket for a card on the mainboard)

The question is: how much of this do you want to preserve? - I was lazy and so I decided that I would not worry about the front USB and upload function. Two back USB slots should suffice for accessing USB media and my Canon printer, because I wanted to preserve the original front of the 1541 as much as possible.
On the other hand, you could replace the drive front with a 5.25 USB card reader and add another button to preserve the "upload" function. (I did not try this.)
In my case, I have decided to leave the front intact.

If we look at the back of the devices (Thecus on top, Commodore below), we find that all there is to do is cutting a hole for the Ethernet connectors (right).

Furthermore, you should think how important you consider the noise emission of the spinning harddisks. (Perhaps they will not spin that much at all, because the N2100 can power them down when not in use.) In that case, you will not need to worry about wrenching two 5.25 inch harddrive enclosures into the 1541. (I did not have much of a choice, because I also use it to stream movies and music in my living room.)

This is very straightforward. Just unscrew all the nice old bits of interior. Preserve the 5.25 front blend of the floppy drive. We will later hot-glue this into the hole. As if nothing has happened.

Also make sure that you leave the connectors of the Power LED (the round green one) and of the drive LED (the small red one) intact. You may later stick them directly onto the board of the Thecus.

Now is also a good time to disassemble your Thecus N2100. Before you do that, you want to test it thoroughly - today is the last day before you void its warranty!
Then remove the lid, the fan, the cage and the main-board (it comes off if the cage is gone). Finally, unscrew the riser card from the cage.

I have decided to put my harddrives into Scythe Quiet Drive enclosures. These are black 5.25 alloy boxes, filled with a rubber mixture. The HDs are wrapped into stainless steel and some heat-conducive sheet, and are then encased in their black outer shells. Very beautiful, very black, very quiet. Unfortunately, very bulky too.

After some hesitation, I have found that only one setup was possible, given the available parts and constraints:
- The back of the Thecus mainboard is aligned with the back of the 1541.
- The first HD is put in front of it. To make it fit, it has to be rotated by 90 degrees. The very beautiful, very black and very quiet HD enclosure will have to be cut by about 2 cm to fit. The cable connectors of this HD have to be made long enough to reach to the riser card on the Thecus mainboard.
- The second HD is put above the mainboard, and partially above the first HD. It does not need to be cut. But in order to keep it away from the components of the board, we use the original drive cage of the Thecus (well, after some mutilation).

The first image show how this arrangement will look like eventually.

For now, I just shorten the Quiet Drive enclosure. A surprisingly easy process, because of the soft metal. After I was done, the Quiet drive is just as quiet as before, only shorter.

Even if you do not want to use bulky HD enclosures, you will find that the drive cage of the Thecus is slightly too high for the 1541, so it has to be cut. Also, it stacks the harddisks too tightly for passive cooling, so we can only use a single slot anyway.

To use that drive cage as a bed for the second HD, we cut its roof away. Then we flatten the rests/latches of the upper HD slot.

The sides of the cage have to be bent open in order to use it as a table for the 5.25 inch HD enclosure. The height of the bent is important: if you go too low, you are inconveniencing the parts on the Thecus mainboard; if you bend too high, the HD is not going to fit into the 1541. The upper end of the mounting holes for the lower HD marks the right height.

Before bending, place a small cut at the back of the left side of the cage to preserve the mounting holes of the Thecus riser card.

One more exercise in cutting things: The mainboard will need something to rest on.
Just cut a rectangular frame from the PVC bottom of the Thecus case, so you preserve the four original posts. (You will want to cut out the space inside the frame to optimize air-flow through the 1541's bottom holes.)
Also, while you are at it and have not already done so, cut the hole for the Ethernet connectors into the case of the 1541.

On the picture, you see the roughly cut frame along with the mutilated drive cage. Hot-glue the frame in place, so that the connectors of the Thecus are aligned with the openings in the 1541's backside.

Now comes the tricky part: soldering the main button. Fortunately, this is not much of a challenge.

The main button of the Thecus sits on the left side of the mainboard. We have unsoldered the switch and replaced it with a couple of pins, but I recommend against it, because this turned out to be a rather fragile solution. It is easier to solder two fine wires to the back of the board, directly to the contact pins of the original switch.
Connect these to the new main button on the front of the 1541 (I will put mine into the hole of the floppy latch).

The Thecus has quite a few LEDs, but I am not sure that we need them. Since the LED set of the Thecus is connected to 20 pins in the front of the board, you may connect as many as you like. (Last time I looked, they run at 3.7V, so you might to use resistors on small LEDs).

Here, I simply connect the main power LED to pin 7 and 16 (no resistor needed), and the floppy LED to the LED of the first HD. Because my Thesus runs in a RAID1-configuration, both drives are accessed in parallel, and a single LED will give enough visual feedback.

We are almost done. Now is the hour of the glue gun:

- Hot-glue the power button into the drive front, and hot-glue the drive front into the casing.
- Hot-glue thin strips of packing foam into the front corners of the casing, so the first HD can come to rest on them without transmitting too many vibrations.
- Hot-glue similar strips to the drive cage bed, to do the same for the second HD.
- Hot-glue a small spacer cushion on the first HD enclosure, so it becomes level with the drive cage.

Finally, connect all SATA and power cables for a last time. Cushion the top-most HD, so it is squeezed in place within the 1541.

Test.

Carefully lower the lid of the 1541 on the whole affair (it should fit snugly) and screw it shut.

In its default configuration, the Thecus N2100 will check for its fan in regular intervals. It will not find it now, and because it does not like this, it emits an ear-shattering beep every 30 minutes. To cure this, install the META module (download instructions in the Thecus user forum), which performs several configurable scripts on startup, and offers an option to turn the fan check off.

Since applying my modification, the Thecus has run many weeks without incident, stores files, serves iTunes music and manages my printer. During heavy harddisk activity it heats up to about 45° C, which is very acceptable. And when I sit next to it in a quiet room, I can hear a faint hum from the disks, which is drowned by the noise of the unsilenced harddisks in the PC at the other end of the room.