Quote Originally Posted by CNCRY View Post
So now I'm thinking to mount to a phenolic (insulating) sheet so the mounting bolt does not touch the cabinet back plate directly. The transformer also has an earth wire.
Any issues with this, or better suggestion people use?
I'm going to throw a spanner in the works here and point out that I've built dozens of machines that use the bolt thru chassis method with rubber pads and I've never had any issues with shorts, fires or getting zapped with stray volts/current etc.
Like Clives mentions it's a Big No No earthing to the bolt but other than that then you won't have any issues provided the transformer sits on the rubber pads.

So just get on with it and don't worry is what I'm saying. If you want to put a rubber washer on the bolt then why not for what it costs but I wouldn't mess around with Phenolic boards etc.