This transformer has a little weld down the side, seemingly to keep all the metal plates together
And some small welds on the bottom. These and the glue were all that was keeping it together
I decided to angle grind them off, a drill would of gone too far into the transformer
And then very very carefully chiseled from the top and sides to separate.
Removed. I managed to split the plates here unfortunately, but its holding up OK, I will re-epoxy them when I am done testing.
Very carefully removing the coils with some wood and a hammer.
Slowly getting the coils out.
After getting the two coils out I replaced the large coil and then wound my own coil with the heavy gauge wire. Then replaced the ‘I’ piece of the transformer. It holds itself on there fine for now but I will epoxy this up before I am finished.
Now I need to make some wire holders and electrodes. while I’m testing I am just going to use some scrap copper pipe
Drilled and tapped a M6 thread into the side of the pipe and bent over the tube halves to make electrodes
A single bolt holds the wire and electrode
Some scrap wood makes the testing a little easier. Also helps me figure out what will work in the final piece.
A spring from an old washing machine helps ensure the electrodes move away from each other
Also had to fix this little overload protection thing. I noticed as I removing the coils there was a small component attached here that I didn’t realize was some sort of overload protector (I assume) or perhaps a thermistor to stop it overheating. For now I just twisted and taped these wires together, seems like a good idea to put it back in for the final product though.
Disclaimer, you really should not do this. Don’t try this unless you are really sure you know what your doing. Mains is dangerous, and microwaves even more so.
Work in Progress
Picked up a broken microwave from freecycle
Ok, Sticker.
Getting the top off. There is a pretty bad smell coming from this microwave
For something that is not meant to be user-serviceable all these components came out really easily. Here is what I was after
A little disappointed its a small plastic transformer. I was expecting something bulkier and with a stronger metal case. But I will try it anyway
Removed it from the board
Removed the copper with some clippers and a screwdriver. the plastic is very brittle and breaks off easily, need to be careful
All the second coil removed
Picked up some heavy duty cable from scrap at work
Gave the secondary coil a winding to have a quick test
Wired up a cable to a chocolate block
It didn’t really work
Another microwave
and out of it a new transformer, much more like what I was looking for. I also bought a circuit breaker so I don’t necessarily blow the mains if this one is faulty too