Which materials for transformer enclosures.

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Sep 18, 2021
California USA
So recently I have been kicking around several ideas. One was bell ends or not. I like the idea of building transformer covers on a tube amplifier where the back is vented to allow air flow, also allowing the use of "L" brackets rather than bell ends. Why? To dissipate heat. I tend t run my amps for many hours at a time, like 16hr days or more, as I work with background music on.

Here is where I put them in cans with resin(see attached photo) to see if this would damp lamination vibration and make a difference in OPTs. The resulting problem is where normally my output transformers would not get very warm these do. But I really like the idea of the binding posts being directly connected to the transformers so as to reduce any possible interference, not that there is much to worry about this anyway. It was just that the particular amplifier I built these to go on was pretty packed inside as I shoehorned the parts in already. I tend to overrate things like resistor wattage and capacitor voltages, I mean by several times like 500%. So if a resistor will need to dissipate 2w I will use a 10w resistor. So I run out of room and my internal wiring doesn't look as neet as it could. But I digress, as tangent is my middle name.

I was considering using other materials as end bells for my transformers other than metal, particularly output transformer end bells. Why? well, there is this thought of flux jumping the gap on single-ended transformers with a metal end bell attached. that make me feel a little suspicious at times. At higher power could the OPTs distort with higher amounts of peak currents because of this? At first I was concerned about using flammable materials, but then they often use paper and masking tape in transformers, and they are more flammable than wood.

So why not wood for end bells for transformer covers? Also is there a good sinking material to fill in a can with that will help with heat dissipation? Regular plastic resin doesn't seem to work super well. I am thinking now of not filling the transformer covers and venting them but still mounting the binding posts to them.


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