The iMac Classic
[originally submitted to the MacMod contest in 2004]
disclaimer: This project ran the way it is depicted here until I ended up with an iBook motherboard that became the iVCR. At that point, I lost interest in continuing to evolve this project. It served well, though, and I post it here as a historical piece in my timeline of mods.
Intro
This project was born when someone gave me an original iMac that had the infamous bad flyback, causing it to crash as soon as the video tried to turn on in the boot process. I had been working with an old 6500 to set up as an iTunes jukebox for our entertainment center, but was constantly running into its limitations. So, when I received this, the iTunes jukebox became a more real possibility, along with general file and iTunes serving. I did pull the guts and start using them right away, minus the tube and the half of the power supply that powers the tube. I then got everything installed and ready to go, along with a RAM upgrade, and hooked it up to our tv with an old Apple Presentation System. The only problem was that having exposed computer components on top of the entertainment was dangerous with 2 little children, so I had to get cracking!
The first idea I had was to put the guts in an empty VCR shell, which would have been cool, but the space limitations just wouldn't allow for it no matter how creative I got. I had recently been given an old Classic II and had fallen in love with the design, so I started toying with the possibilities of using a similar case. To make a long story short, I got an empty Classic shell from Ron Krell on the Lowend Mac swap list.
Planning
I originally wanted to fit the guts of the iMac into the Classic case without leaving any external evidence(other than the missing tube of course) that anything had been tampered with. I spent hours and hours trying all kinds of crazy ideas, and finally accepted reality. There would simply have to be some bolts showing on the outside or this would never work(at least not without driving me crazy in the process). Besides, every day longer that this took was one day more for the kids to start getting interested in it.
So, with that having been accepted, I went with the practical method and decided to bolt the motherboard tray and the power supply board onto the inside sides of the case, reusing the area where the Classic's power connection resides for the iMac's ports. I removed the hard drive carrier from the motherboard tray to make it more compact. I had to remove the cover on the back of the case for the monitor adjusters and cut that whole area out with my rotary tool. This left ample room for the iMac's ports, but meant that I would need to later design some sort of covering to prevent it being a gaping hole in the back. I had to rotary out a hole in the bottom left corner of the back for the power connector of the iMac's power board. I then measured my holes, drilled them out, and bolted these 2 major components in place for testing. At this point, I just mounted the hard drive in the tray from the motherboard cage, and left that sitting loose on the bottom of the case bewteen the motherboard and power supply. I was able to run it like this for a while to buy myself time to figure out more of the final details.
Finishing Stage 1
I finally decided that I definitely wanted to paint the case gloss black, and make the Apple logo gloss red. In retrospect, I would have used a satin or semi-gloss finish and may even repaint it before I call it done.
There was still the issue of the gaping hole on the front of the case. I really wanted to mount a small 9 inch lcd in that area, but couldn't find one cheap enough to justify. The more I thought about it, the text on a screen so small might not be very readable going through a composite adapter anyway, so I didn't want to risk wasting the money. I decided to cut a piece out of the side of the iMac shell to fill the hole, and mount my case fan into that. This would give me the best possible airflow to pull air through the case. While it may not be the ideal place for it, putting it in the back would not achieve much because it would not pull any air through from the front, since there is no good ventilation toward the front of the case. My compromise seems to have paid off, though, because the inside of the case is staying pretty cool and I haven't had any problems with overheating. I mounted the fan toward the upper right corner of the screen area so that it is above the power supply, which generates the most heat, so that it leaves room for further additions to the front plate, and so that it creates a cross-draft from the vents in the back of the case. I cut another piece from the blue of the iMac case to cover the floppy slot. It is attached by velcro in case I ever come up with a use for this slot.
The speakers from the original iMac are mounted against the area below the crt space, pointing down at opposite angles so that the sound goes down through the vents under the crt. This will allow it to be used as a portable jukebox in case there's not a stereo to hook it into.
I haven't yet found a short ADC extension that I could use to transfer the monitor connection to the back of the case, so, in the meanwhile, I am having to run the cable from the Presentation System through a hole in the back and into the case to connect it. Ideally, I would like to come up with a better means of connecting this to displays, but I haven't found a perfect solution yet. This is functional in the meanwhile.
Another detail is that, after using it for a while, we decided we wanted speakers in both the kitchen and the living room, so I cut a few "rungs" of the back case vents out and mounted the double-headphone jack there, which now makes for 3 stereo outs on the back of it. As they are all tied to the same source, though, we have to use a set of speakers with built-in volume controls in the kitchen in order to not be at the mercy of the setting in the living room.
The Seagate 80GB drive is mounted into a removable drive tray from a pc case, which is velcro'd onto the bottom of the case so that I can pull it out as needed without having to undo a bunch of screws in odd places. This hard drive holds our entire CD collection in Apple Lossless format! Woo hoo! I am now starting to add mpeg4 movies to the drive, though, so I may have to upgrade it eventually. This drive also acts as the backup drive for my home network. All in all, this iMac makes a pretty darn good file server.
Caveats
There are a few caveats. One is that the Presentation System is limited to 640 by 480 resolution at 60hz refresh. OS X won't boot into this setting no matter how many times I tell it otherwise, so I had to write an AppleScript to run the awesome command line utility cscreen as a login item to set the resolution properly. Once that runs, everything is okay, but the edges of the screen get cut off because the Presentation System isn't shrinking the screen to fit in the viewable area. The other problem is that some parts of OS X can't be accessed in a 640 by 480 setting, requiring me to connect via VNC, switch the resolution to 800 by 600, do what I need to do, then reset it to 640 by 480. This mostly comes into play during System Updates, where the OK buttons are way down around 585 pixels or so. Having to keep a VNC server running all the time for these rare occasions probably adds a little more overhead to the processor and networking, but is worth it in the long run. Besides, it allows me to use my laptop as a "remote control" when we are watching movies on it. :)
Another caveat is that I am nervous about adding one of those G4 upgrades to it because the heatsink is a mere inch or so from the side of the case, which doesn't leave room to add any cooling. Right now, I'm banking on the fact that the G3 doesn't run very hot and I'm taking my chances with what little airflow it has. The tray is mounted in such a way, though, that the area above it is open, so that the heat can rise out of the space between it and the side of the case.
A small caveat is that it currently has no optical drive. This isn't a big deal because I am able to use an external usb adapter with an old cdrom when I need a drive, which is not very often. If I ever add one, it will have to sit on the bottom of the case and show through the front bottom in the dead center. That would be the only place where there would be room, although it would look pretty ugly. I thought about putting a dvd drive there so we could watch dvds on this thing, but I am not sure this hardware could even play back the movies smoothly. I decided it wasn't worth the energy.
Future Additions
I just bought an lcd temperature sensor so that I can run the lead back to the heatsink to keep an eye on the processor temp. The temp isn't a major concern right now, but I plan to upgrade it to the 333mHz processor(if I can ever find one, darn it!), and that will need to be monitored so I'll know whether or not I need to try and add some further cooling in that area. I plan to mount the lcd in the front plate, under the fan, which will leave room on the left side still for future add-ons.
If I can find a cheap enough 5 or 6 inch lcd that might fit into the left side of the front plate, I may experiment with that. If you are reading this and have one you could let me borrow(or could part with really cheap), please consider sending it to me so I can test the idea before wasting the cash.
There is an open serial port on the extra port board inside. The IR receiver/sender used to be attached to that. I would like to get that IR going to use with remotes, but I'm not sure it even works under OS X, and I really don't have time to learn about the IR stuff anyway. So, I would like to find some OS X compatible device to attach to that. If there are any serial tablets that would work, that would probably be a good addition to this project. Or a game pad or joystick. If you have any ideas or suggestions regarding this, please send them along.
I am pondering doing away with the Presentation System, and putting an old Apple monitor in a dead space in our entertainment center to connect to it. Or, if I can find one of those mezzanine slot video cards, I may go that route, which would allow me more options for displays. Whatever happens, the current setup is not ideal, and I plan for it to evolve.
One day... X10 server. :)
Peace,
Todd Russell