Toroid Mounting Caution

[bzdang]

Hi everyone, I'm new to the forum and to diy amp-building, have a lot to learn, but I do have a safety tip for other first time builders. It's been mentioned before but was buried in a fuse post in Pass Labs, where us newcomers won't find it when building our chip amps and chassis.

If you use a metal chassis, avoid direct contact between the toroid mounting bolt/nut/washer and the inside of the top or lid.

You might form a shorted single-turn secondary winding consisting of the mounting hardware and the chassis! Could get fairly warm before the fuse blows.
Paint is not sufficient protection as it will chafe through. If space is limited, put some durable insulating material between the hardware and the lid.

Dave