These 2.5" drives are TINY... this is going to take some doing!
The software on the PIC times the platter rotation to calculate the correct timings for the LEDs, so I should be able to simply swap out the drives and have it run with no software modification. Can't get any easier than that.
|After removing the cover I could see the read/write arm was stuck. Removing it fixed THAt problem right away and it spun up nicely. I was also happy to see two platters. Removing the bottom one gave me enough room to work with. You can see the current work in progress. Hooked up to the controller board of the 3.5" version it spins up and displays perfectly. The only problems is I don't have any LEDs mounted.. I had to hold them and shine them under the disk to faintly see the patterns.|
|You can see the space problem here. This is a standard LED sitting next to the spindle. It's huge, there is just no room for it. Even surface mount LEDs of the desired brightness will need to have places machined out for them.|
|Machining the disk was also a challenge. The disks in this drive are NOT metal I found when I cracked one side clean in half. With a bit of aluminum tape to reinforce it I tried again only to find the disk shattering under the cutting wheel. It seems to be made of some sort of crystaline substance.. might be sillicon. It's very brittle and delicate. With paitence I managed to cut a slot into the other side and patch it up enough to glue on a magnet and test it.|
|Thats a nasty little fracture. It took a long time to cut through and it devoured the cutting wheel. It also got very hot, hot enough to turn the outside of the cutting wheel a nice cherry red. Annoying stuff! Luckily I still have the second platter. I'll try and machine it once I have the rest finished.. it's too delicate to risk working with right now.|
|Although there is no room to mount the LED strip, holding up one of the LEDs to the spinning platter shows that it is indeed working correctly. So I just have to find the right size and mounting method for the lights and I'll have my mini clock. Much smaller, but a heck of a lot quieter, especially when I put a clear plexiglass cover on it. It all runs on 5v too, so easier to power as well. It will make a nice portable light show when it's finally finished. The circuit of course is going to have to be mounted to the back, no way I can fit it inside. Hmm.. maybe with surface mounted parts...|
Oh.. I found another drive to try building a clock out of. It's a little smaller...