Rubber washers on TRANSFORMERS???

[kyrie48]

I just put rubber washers between the case and transformer in several amps I have. Most are vintage with slightly more buzz/vibration than new ones, and this really helped solve the problem.

NOW, question is; have I created a problem with grounding, or anything I'm not thinking of???

TTYL, kyrie

 

[Conrad Hoffman]

The transformer cases still need to be grounded for safety reasons, but IMO transformers vibrate and there's nothing wrong with a little isolation so the rest of the amp doesn't act like a soundboard. I'd just use a couple ring lugs and a short loop of heavy wire for grounding.

 

[Gordy]

I think there was some discussion of this over in the Tubes section of the forum. Might be worth a search over there...

 

[jaycee]

I'm assuming you mean EI type transformers.

If the transformers are bolted down to the chassis, with just a rubber insulator between the base of the transformer and the chassis, then they will still be electrically connected via the bolts. You may want to add some toothed washers just to make sure. Check with a resistance meter and you will probably find the casings are still earthed.

 

[kyrie48]

Sorry, should've been more specific... I put washers between the transfomer and amp, but no washer on the bolt. I was afraid that might really ruin my day!!
But was still concerned this might not be proper... looks like makers would do this from the factory. But, I guess they hope stuff is replaced before there's any issues with such.

That cures all my ills about mounting... huge help. Thanks ALL!!
TTYL, kyrie

 

[taj]

And for toroidal transformers I throw away the wimpy thin rubber rings that usually come with them and cut out rings of flat thin (1/8" or whatever) high-density packing foam (either styro or rubber) before tightening it down. No chance of any buzzes or rattles, and it keeps the transformer very stationary.

We have an excess of this type of scrap material at my workplace, so it's easy for me to get.

..Todd