I've been spending this evening for a just cause: Fixing our flat's toaster. It broke down somewhere around yesterday. At first, the toaster would not stay down and on, but later on the glowing wires wouldn't do their glowing act at all. Thinking I'd just have a quick look and repair the thing proved somewhat of a challenge...

Challenge #1: Screws

So, while waiting for our fries to get fried, I thought I'd pry it open. That sounds easier than it is, since they used some kind of weird screw type. Fortunately, I had a screw bit in for that type, unfortunately, I could not put it far enough in to actually reach the screws. So, another approach was needed.

From an old pen clip, I managed to build a nearly-working screwdriver-equivalent device. Bert managed to bend and file it a little more and I was eventually able to use the thingy to unscrew the screws. I did pretty much kill my (fake) Dremel in the process, but it was nearly broken anyway.

Challenge #2: Power and metal

Now I got the casing off the toaster, I could look inside. After some looking and thinking, I formulated a theory about how exactly the power distribution inside the actual toasting unit would function. To test my theory, I would need better access to the actual glowing wires, but they were hidden behind sturdy looking metal plates. After some poking around, I applied golden rule

1: If using force isn't working for you, you're not using enough of it.

After bending some metal and applying some controlled violence, I managed to uncover the guts of the device, miraculously without even breaking anything. When I got there, my theory seemed to be pretty accurate: The full 220V power was applied to the glowing wires to heat them. Through a simple voltage divider, around 10V was tapped off for the other components: The timer and magnet to hold the bread container down.

Challenge #3: Heat

After some measuring of voltages, I managed to find at least one cause of trouble: There was a cut in the glowing wires somewhere. Although I was not able to visually confirm the cut, but I knew it to be there! Intent on fixing the wire cut, I started opening up the device even further, so I might get closer to the cut and fix it. I already took out my soldering iron to (temporary) unsolder some stuff and later on solder the wire cut closed, when Bert reminded me that using solder for wires that are meant to get really hot, might not be the smartest of plans. So, next plan...

The real way to fix this, was to weld the stuff together. Since I do not know how to weld and did not have any welding devices handy, I decided I'd go for the second best solution: I pulled one end of the wire cut completely loose, found another spot on the glowing wire a bit further on, and tied the loose end around it. That should do it!

Challenge #4: Magnetism

Well whaddayaknow? The toaster started glowing when I pushed down the bread-container! Only, it would not stay down, as a toaster's bread-container is supposed to do. During normal operation, an electrical magnet would get turned on, holding the bread-container down until some period of time has passed, deactivating the magnet and launching the bread-container back up, which in turn opens the main power switch, turning the entire device off. Toasters are actually pretty simple!

So, somewhere, the toaster's circuits were broken. Following the path, I found a simple rectifier, to turn the AC power into DC for the rest of the circuit. Through a some reverse engineering, a lot of thinking and even more measuring, I determined that one of the resistors was broken.

Challenge #5: Bert

Fixing this was simple: I just had to replace the resistor with a working one of the same value. Rummaging about in my own spare parts didn't get me anything, but looking at the computer junk collection on the walls of our hallway quickly found me an old 486 mainboard containing the required resistor. Unfortunately, the collection is Bert's and he was not ready to part with the board just yet. Some more searching got me an old VGA card, containing the required 10 ohm resistor.

Desoldering the broken and new resistor proved trivial and was completed in a few minutes. Testing the toaster thereafter was successful: We once again had a working toaster. That is, there was one more challenge to be conquered.

Challenge #6: Reassembly

This is the worst part of every repairing or modding project: Reassembling all the parts brutally^Wcarefully removed from the device back into the complete thing. Fortunately, there were not to many parts, so reassembly went rather smooth (naturally using enough force). While I was reassembling, Peter tried to find replacement screws (to prevent challenge #1 in case the toaster had to be opened again sometime) while Bert tried to mod the original screws to accept a normal screwdriver. Unfortunately both failed, so I jammed the original screws back in, hoping I don't have to open it again anytime soon.

This does not seem real likely, since it is unlikely the dodgy and improvised tying-wires-together tactic will hold for long. The next time the thing breaks, it will be final. But, for now we can have our toasted bread again!