/diy/ - Do It Yourself

I ended up building the transformer shown in >>885647, except without any load connected to the primary and with a slightly different winding ratio (50:3). It was basically the primary connected directly to a household power outlet via a power cord. On the secondary, I put a 240 ohm resistor rated at 10 W, and a multimeter in parallel with that resistor to observe the voltage.

Contrary to my expectations, one part of the primary winding which was connected to the power cord exploded the instant I plugged it in, and sent molten copper in all directions. The device is now unplugged from the mains, but I am uncertain as to whether the iron core might be carrying a dangerous magnetic field which could collapse rapidly if I shorted the primary. I cannot begin dismantling it because I'm afraid to touch it.

Based on what I explained, is it safe to handle as long as it remains unplugged? If not, how would I render it safe?