Tips for mount toroidal transformer

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can you tell me, how you do mount toroidal transformers into a rack enclosure?

I know, with the bolt, rubber pads and steel washer. But, for do it this way I need to drill the chassis and the bolt has a big head, and If you mount the rack into cabinet with other devices, this will be a problem with the bolt.

Any advice?

With mounting toroidal hardware, two large rubber washers, two circular plates and a central bolt nut and spring washer is usually provided.

Although most would consider this as job done, you need to also source a insulation washer that includes the central bolt thread, to isolate chassis ground from the central bolt. This is rarely provided - along with sufficient thread length to do the job properly. See creepage and clearance Electrical Safety Requirements

Another precaution rarely observed, is caution when using toroidals particularly small ones in circuits with very little current draw, as flux density is greatest with no load.

Transformers Part 1 - Beginners' Guide to Electronics
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Joined 2003
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From the other forum:
> It's possible to upload some photos?

Of what? A dimple? A wrench socket? A bolt?

The "big money" is in tapered dimples. Lots of tapered dimple-dies for that job.

You only need a flat dimple bigger than your bolt+wrench, deeper than your bolt head, and nobody will see it. You can do a respectable job with two sockets and bolt or hammer. (You can even use a round rock on sand, but it takes a steady hand.)


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Maybe he was thinking of the more-common 'bolt mounted to the bottom plate', forgetting that your mounting plate/post will insulate.

Hey, that creation is beeeautiful! Wouldn't be surprised if you get a bunch of requests from folks here that want them, too! :cheers:

If you decide to produce them, you might want to consider a filet around the foot of the post -- less likely to snap off if the equipment ever gets dropped. Since you're 3D printing them the extra complexity doesn't cost much.

Great work,
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This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.