A window mod is a type of case mod which involves replacing part of one or more of the sides of your computer's chassis with a clear material of some sort, usually some type of plastic. The result is a window which allows you, and anyone else in the general vicinity of your computer, to see the inside of your chassis - your motherboard, your graphics card, your hard drives, and such.

Pros:
  • Looks wickedly cool, especially if you have a light source inside your chassis
  • Nice to show off at LAN parties and the like - impresses your friends
  • Allows for visual inspection of your hardware without taking the chassis apart
  • Boosts your ego every time you look at it
  • Some people will think you are l33t because you're a case modder
Cons:
  • If you make a mistake during the mod, you might ruin a perfectly good chassis
  • Having a modded chassis automatically makes you a computer nerd in the eyes of Joe Sixpack
  • Costs time and money you could spend on something else
You can zero the risk of ending up with a broken chassis and reduce the effort and time required to perform the window mod by buying a pre-modded chassis, however that brings with it the following cons:
  • A pre-modded chassis is much more expensive than an unmodded one plus the cost of doing the mod yourself
  • Factory mods are sometimes of poor quality (very thin plastic used for windows, etc)
  • Some people will consider you lame for having a pre-modded chassis and will laugh at you for trying to be l33t - you are likely to meet such people at LAN parties
  • You can't call yourself a case modder or consider yourself l33t (as if you care about that)

I will now proceed to describe my own most recent experience with window modding in the hope that it will give some advice to those thinking of performing such a mod on their computer.

Stage one - planning

A good place to start is to depict in your head what you want the final result to look like, and then draw up some sort of plan on how to accomplish this. Consider the problems you might run into beforehand and figure out solutions as well. This minimizes the risk of you ending up with a botched chassis.

Since my chassis is of the 4U rack-mount variety, it has all the drives and such in the front, and the motherboard is mounted horizontally in the rear. There is a wall consisting of three heavy-duty 120mm fans in the middle (very noisy), separating the "drives area" from the "motherboard area". I decided to put my window over the motherboard area, since that's where all the cool stuff is. I wanted it as big as possible, so I measured the motherboard area and subtracted 40 mm from each side. This gave me a concrete set of measurements to work with: 300 x 350 mm (the entire top side of the chassis was 643 x 427 mm). I decided that one centimetre of overlap on each side would be sufficient, thus I needed a sheet of transparent plastic about 320 x 370 mm in size.

For my previous window mods, I'd used 1mm plexiglass sheets. However, while cheap and easy to work with, plexiglass isn't very durable in 1mm sheets, and cracks very easily. This time, because I was modding the top rather than the side of the chassis, I needed a window that was somewhat above-average in terms of durability, as someone might put their coffee mug, or suchlike, on top of it. My choice of materials thus fell upon 3mm Lexan, a very strong and light polycarbonate, practically unbreakable by any forces a computer chassis is likely to be subjected to. The downside is that Lexan is quite expensive. I went to various stores dealing in glass products around where I live, most of them stocked Lexan, but the prices varied between expensive and ridicilous. The lowest price I found was SEK 825 per square metre (that's about $106, or €91). Some stores wanted more than SEK 1200 for the exact same product.

Having decided upon the material and size of the window, I proceeded to try and anticipate the problems I would likely face. I quickly identified two. One, the chassis I was about to work on, an Image and Shapetek EYE-4870L, was made out of 1.2mm SECC Zinc-coated Japanese industrial-grade steel. Not quite the easiest material in the world to cut through if you haven't got professional-quality tools. Two, I normally have a monitor sitting atop my chassis. No matter how hard I tried, I wouldn't be able to make a window that could sustain its weight. I decided to solve this by building some sort of stand for the monitor that could be placed on top of the chassis, resting on its outer edges. I drew up plans for the monitor stand and spent two hours building it using a few left-over pieces of wood and some nails. I then tore apart an old NATO Battle Dress Uniform and used a staple gun to cover the stand in camo cloth. The result was certainly eye-pleasing (at least in reduced light conditions), and the stand fit perfectly atop my chassis.

As for problem number one, I solved it by buying myself a very mean-looking drillbit (cost me SEK 100, or $13, or €11) and borrowing my father's powerdrill. Professional-quality tools, check.

Stage two - cutting the damn hole

When it becomes time to do the actual work, a lot of people start feeling a bit anxious, especially if they haven't done anything quite similar before. The risk of ruining something you've spent a lot of money on becomes apparent. Good planning is very important here, because even if you didn't plan very well, so long as you think you did, you will feel a lot more self-confident.

Having removed the top side from the chassis, I used a marker and a ruler to draw the contours of the hole I was about to cut. I then double-checked to make sure that the measurements were correct, and they were. Having done this, I put on my safety glasses and ear protectors, and proceeded to drill some holes. About one every 10 mm along the inside of the entire contour of the would-be window, to be precise. There were two reasons why I chose this approach: Firstly, because it would take ages to cut the whole thing using only my Dremel MultiPro, and second, because Dremel reinforced cutting discs are bloody expensive. By using the drill, I reduced the amount of metal I had to cut through using the Dremel by at least 60%. Of course, had I had a good hacksaw at my disposal, I wouldn't have needed to use the drill.

Having finished drilling the holes, I used the Dremel to cut away the rest of the metal. I also used the Dremel to sand down the edges and make some nice rounded corners (because I like round corners, not because there's any particular advantage to having rounded corners).

Having finished cutting, I removed the now somewhat perforated piece of steel that had once been part of my chassis. What was left was a perfectly good piece of steel with a 300 by 350 mm hole in it. I proceeded to cover the edges of the hole with a black rubber stripe. Some people don't like having a stripe between the metal and the window - I like it because I think it looks nice, and it doesn't matter if your hole cutting skills are a bit less than perfect if you're going to cover up the edges with black rubber afterwards anyway. It's very hard to get a perfectly clean cut using only a Dremel tool.

Stage tree - turning the hole into a window

Once you're done with the cutting, it's time to attach the piece of plastic that is going to be your window. This is not very hard to do; it's harder to decide just exactly how to do it. Some people prefer to use bolts (which looks rather cool but requires you to drill even more holes through your precious chassis), other people use ordinary screws, others simply glue the window in place. I prefer to use epoxy. It's very strong, won't come off easily once hardened, and works very well for bonding two completely different materials such as metal and plastic. Also, unlike "super glue", epoxy doesn't harden too quickly, giving you plenty of time to work. Be warned, however: epoxy gives off a rather annoying smell while you're working with it. Once it's hardened however, the smell goes away.

The sheet of Lexan which I bought was delivered to me nicely wrapped up in plastic foil to prevent it from being scratched during transport. I used a scalpel to very carefully remove the plastic foil around the edges. That way, I could glue the window into place, wait for the epoxy to set, and then remove the remaining plastic foil, ensuring that the window wouldn't get scratched, or worse, get any epoxy on it other than on the edges. As I already mentioned, epoxy is hard to get rid of, you don't want any of it on the visible parts of your window or your mod is going to look like crap. Anyway, having applied the glue, I left the assembled part alone for an hour. I had not anticipated any problems with this part of the mod, nor did I encounter any.

Stage four - putting your chassis back together, feeling l33t

This is the part where you find out if your mod was worth the work you put into it. If you put the side of your chassis back on only to find that hardly anything can be seen through it, it's probably because you don't have a source of light inside your chassis. A neon or CCFL tube is inexpensive and can be hooked up to your computer's PSU using an inverter and a slightly modified Molex 4-pin power connector. There are guides on how to put lights inside your chassis, so I won't go into it here. Suffice to say that a light source inside your chassis is almost essential in order to get the most out of your window mod in terms of esthetics.

Having finished my window mod, I tried to put the now-modded top side back on the chassis, only to find that it didn't fit. Oops. With the window added, the modded part of the top side had now gone from being 1.2mm thick to being 5mm thick. A metal beam, mounted horizontally above the motherboard, was now in the way. Having removed it (a procedure I will not go into in any detail whatsoever) the modded top side fit beautifully. May I add that it looked wickedly cool?

Stage four - feelin' the love, conclusion

In conclusion, I would like to recommend the window mod to anyone who frequently attends LAN parties and the like and who has nothing better to do with a couple bucks and an afternoon or two. It is perhaps one of the best mods for beginners, since it's relatively easy to do and won't result in a dead computer if you fail. (Though it can result in your chassis looking like utter sh*t.) It's also the mod that adds the most to the esthetical appeal of your chassis, if done well. This is especially true if your chassis has some type of internal lighting, see above.

(This is where I would put the pictures of my window-modded chassis, had E2 supported images in write-ups. If or when such support is added, I promise to put some pictures here. Until then, you'll just have to imagine it. Thank you for reading.)