teardown

I pulled this Razr clone from next to the dumpster. It had a loose front wheel that required tightening one bolt to fix. After I got it working I took it out for a spin. Wow, am I bad at riding it. To avoid an inevitable and grisly crash I left it on the deck and ignored it for a few months.

After spending the winter in the snow the scooter had developed a nice layer of rust.
I decided to give it to a friend’s kid who didn’t have a scooter. When I looked at it I realized that there was way too much rust on it for any kid to want it. Time for some rust removal.
The firs step was to disassemble the scooter. I took pictures of each area so that I would be able to put it back together later, and so I could share the experience with you.
As you can see the rust even made it inside of the handles. I found it interesting that the caps were held on with a simple knot. That was good for me, it was easy to reassemble.
These ball bearings were the worst part of the project. There was one on top and one at the bottom of the fork. Both had loose bearings. I lost one through my deck, fortunately it didn’t seem to effect the performance. I had to look back at this picture twice to get it back in right. Here are all the parts disassembled and ready to be cleaned. Apart from removing rust I wanted to take off all of the cheesy stickers. They were beat up and proof that it was a generic scooter, not good things when you are a kid.
Here are all of the small parts soaking in a bath of acetone. This did a fairly good job of cleaning off all of the dirt and grease. I used an old toothbrush to give each piece a good scrubbing.

To be continued in another exciting episode…

Dun, dun duuuuuuun.

KeychainWhen I was doing my CFL Teardown I mentioned that I thought the PCB would make a cool keychain. It does. I have had it on my keys for a little while now and it works quite well at helping me find my keys without getting in the way. I like the side with the components silkscreened on, most people like the green side with the traces.
keychainTo make it work as a keychain I had to widen out one of the holes to fit the key ring through. There are a ton of ways to do this, but I happened to have my Yankee Drill sitting on my counter as I was working, so I used that. Next I wanted to take off the excess solder so all the holes would be visible. I was feeling lazy so instead of using a solder sucker I just used solder wick. Once I was happy with the amount of solder I had left I put the keychain in my toaster oven to round off any sharp bits of solder that were left over. This made the board a bit discolored, but it also kept me from cutting myself when pulling my keys from my pocket.

After a few weeks using it the only problem I see is that I am slowly wearing the hole larger. I figure that in a few months I will wear completely through. I could cover the whole thing in a clear epoxy and it would probably last much longer. Probably I will just take apart another broken CFL and use the PCB again.


One of my compact fluorescent lights stopped working recently. Instead of throwing it away I decided to crack it open and see what was inside.
<warning> Electricity can hurt you. If you don’t know what you are doing, get someone who does to help. </warning>

The first step was to remove the metal base and pry the plastic off of the globe. The plastic base, globe and lamp were disposed of. Be careful with the lamp, it contains mercury vapor, not something you want to be breathing.

The main circuit board. Everything was pretty tightly packed in. At first glance nothing is obviously bad. The plastic on the enclosure was a little browned, so I’m guessing something overheated. One part of the large yellow inductor was cracked when I removed it, so that is a possibility.
After a little time with the soldering iron I’ve got a nice pile of parts. I got six diodes, seven capacitors (two matching), five resistors (two matching), three inductors, two matching transistors, a fuse and a nifty circular pcb. Normally I would dispose of the pcb but I think it would make a really cool looking key chain.
Now all I need to do is check the parts that might be bad and put them away in my parts drawer.