Why is my custom microwave transformer producing inconsistent voltage?

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RED119
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So I was attempting to modify a microwave transformer by wrapping my own secondary coil. The first coil was standard from the microwave, around 16 gauge wire, 100 turns, so I was wrapping my coil with around a 16 gauge wire, I put it together, put a weight on the transformer to keep it together and tested it with my voltmeter and it read around 176 VAC... then I kept winding and tried again but only got .123 VAC, I found this odd so I checked the primary coil, it was getting 120 VAC, it was making the buzzing that transformers do (its 60Hz by the way), when I measured the primary coil it got around 180 VAC, the primary coil was getting hot while the secondary coil I wrapped was cold... I honestly have no idea what is going on or what I did but this is odd stuff... or maybe I am just naive. Here are some pictures to help with analysis:
Photo of a disassembled microwave transformer core: three stacked rectangular laminated steel blocks with copper wire visible at the top, sitting on a brown leather surface beside a yellow pencil.
Photo of a cardboard product box with a rectangular window cut out, showing a dark object inside, with partial printed text on the surrounding packaging.
Close-up of a multimeter's red probe touching a bare copper wire wound around a transformer core, with the transformer body and dark carpet visible in the background.
Photo of a disassembled microwave transformer core, a laminated iron U-shaped stack with a center leg, sitting on a dark leather surface with copper wire loose at the right.
Photo of a disassembled microwave transformer core, an E-I laminated core with a wound copper coil around one leg and a white plastic bobbin at the side.
Photo of a microwave oven transformer with a copper-wound secondary coil visible, two black-insulated leads with metal spade terminals on a white plastic connector block, and a grey laminated steel core.


Spool of bare copper wire wound on a cardboard reel, lying on a dark leather surface, with loose wire ends at the upper right.
Homemade transformer coil: copper wire wound around a rectangular laminated core, with two spade terminals on one side and tape-wrapped sections visible.
 
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Discussion

*primary coil is not measuring 180VAC, it around .320VAC (essentially 0)
 
CWatters said:
Shorted turn somewhere?
I don't think so since I re-wrapped the coil with new wire after it happened the first time, but I still think its worth checking, is there an easy way to check if a turn shorted? and should I check both coils?
 
the secondary coil is putting out .142 then going up to .180 then back down to around .142 and back up again
 
:oops: enamel coated wire... forgot to sand off the enamel of the new end... my bad
 
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