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Construction

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Custom Case:

The computer, an IBM Personal Computer 330, originally came with a plain looking IBM desktop case. The original case would adequate for a no-frills desktop system, but I had something else in mind.

Since I'm not very good at metalworking, I started looking for something that's pre-made. I searched various stores for a metal toolbox that had the proper dimensions. They were either too narrow, or too big. Finally I stumbled upon a "circular saw case". Although it's not the smallest thing in the world, it fits nicely in my trunk, the top flips right open, and it has a nifty little carrying handle.

With that part out of the way, next came the task of mounting the motherboard. The motherboard and original IBM case have a proprietary form factor. Since I had no stand-offs, and was kind of worried about getting the openings cut out properly I decided to cut away part of the original case and use it as a motherboard tray. Next, holes were drilled in the motherboard tray, so it could be temporarily mounted in the case. Then the tray was used as a guide to cut out the necessary openings.

Tip: A dremel and a cutting disc work fairly well for this. It helps to cut the holes slightly under-sized. Then use a file, or sanding drum to finish it off.

Likewise, a hole was cut out for the power supply. This was a bit more difficult, since there was no easy pattern to follow. I started by cutting a small hole, then working my way out. Then holes were drilled for mounting the power supply. It helps to make a template out of paper or cardboard. That way it's easier to get the hole spacing right.

With most of the hard work out of the way, it was time to cut out the hole for the case fan. A holesaw makes quick work out of it. It's definitely worth the $10-$15 price tag. I also drilled holes to mount the floppy drive. Since I only plan on using it in an emergency, I chose to mount the floppy drive inside the case.

The next issue to tackle was the riser card bracket. On the original case, it was bolted to the front. This was not an option, because it would block the place where the hard drives were to be. I used a threaded rod to support the riser card. That way the front part of the riser card bracket (right portion of the picture) could be cut away to free up space for the hard drive plate. The threaded rod was attached to the bottom of the case using a female stand-off. Then a nut was attached just below the riser card bracket, and adjusted for height. Then another nut was put on top of the threaded rod.

Drive Mounting:

First, I made the drive plate out of a rectangular sheet of metal. To accommodate for future expansion I made the plate large enough to hold two drives. Holes were drilled in each corner of the plate, and in the bottom of the case.

Then using a spare hard drive as a pattern, I marked where to drill each hole in the plate. Three sets of holes were drilled: one set in the middle for the current drive, and two other pairs of holes on either side. That way I'd have the holes already drilled, when it comes time to add a second hard drive in the future.

The drive was side-mounted to the plate. Then the plate was attached to the bottom of the case using Sorbothane isolation mounts. The mounts have a bolt on one side, and a threaded hole on the other. I put the "hole side" down and attached screws from the bottom side of the case. The nuts were used to fasten the plate to the isolation mounts.

For further shock absorption I purchased three 4" X 4" squares of Sorbothane. I cut two of them diagonally and stuck them to the bottom corners of the case. Then I stuck the remaining square to the bottom center.

LCD Enclosure:

The LCD display also needed its own case. To keep things simple, I bought a 3" X 6" project case from Radio Shack. Although it's not the ideal case, it was adequate for my purposes.

Matrix Orbital does make a mounting kit. It's a bit overpriced, but I was going to order it anyway. But when they wanted to charge some outrageous amount to ship the thing, I said no thanks.

To keep thing properly centered and aligned I made my own template.

Note: The template isn't perfect. It's only intended to be used as a guide.

Then I ordered the following parts:
4-40 3/8" female standoffs (4)
4-40 1/8" machine screws (4)

Using the template as a pattern I marked the rectangular window and the 4 mounting holes. Then the holes were drilled. I had to make a couple of the holes bigger to get the stand-offs correctly aligned with the LCD.

Next I cut the rectangular "window", but left some room around the edges. Then I used a file to get the "window" to match the LCD. The LCD uses four 4-40 screws to hold the display together. The nuts were removed from the back side of the display, and stand-offs were attached to the LCD case. Then the screws were threaded into the stand-offs to mount the LCD in place.

Finally, connectors were mounted on the back of the case. These can be whatever you want, as long as the LCD gets power, and data. To keep things standard, I used a 9-pin D-Subminiature connector for the data. Then, for the power, I used a 5.5mm O.D X 2.1mm I.D coaxial power jack. This will make things easier when it comes time to bring the LCD display inside to test my software. In addition I also mounted a 5.5mm O.D. by 2.5 mm jack for the LCD's general purpose output, just in case I need to use it in the future.

Note: The polarity, and voltage applied to LCD must match the manufacturers specifications. There is no "second chance". Getting it wrong can cause permanent damage to the LCD display.