Trainwreck endbells

[jcsb]

I got a couple of sets of Power and Output transformers for a couple of Trainwreck Liverpool builds that I received with the endbell dented (all 4). Anyways I took one of the endbells off and tried straightening it as best as possible and then I sprayed it with black wrinkle finish paint. Not bad but I thought since I have a machine shop why not machine full endbells that encapsulate the transformer. So I've attached a couple of pdf's showing my initial design. The material is 6061T6 aluminum and I will probably anodize it black. I will have a teflon insert where the wires pass through to insure not damage and have a viton gasket where the 2 halves meet to insure a sealed unit. Any thoughts?
John

[xtian]

Thoughts:

A) You have a lot of time on your hands.

B) I really want a machine shop. Haard.

[jcsb]

Thoughts:

A) You have a lot of time on your hands.

B) I really want a machine shop. Haard.

Yes to A and B was what gave me A.

John

[paulster]

Any thoughts?

Make sure it's not actually touching the lam stack because you don't want to end up with shorted laminations and a very hot and inefficient transformer.

[martin manning]

Don't end bells have to be made of ferrous material to function as effective shields?

[jcsb]

Don't end bells have to be made of ferrous material to function as effective shields?

No as long as there is some other internal shield. I have a couple of options here. One would be to use one of the shielding paints internally or two there are several shielding films.

I admit it would be easier to use a mu metal can, but what's the fun in that?


John

[jcsb]

Any thoughts?

Make sure it's not actually touching the lam stack because you don't want to end up with shorted laminations and a very hot and inefficient transformer.

Yep I thought of that and it has sufficient air gap along with the fact that it is anodized. I did have a thought of potting it too. The last time I did this it turned into a big mess, but worked.


John

[jcsb]

Hey, I do want to thank those who have asked questions since making this right the first time is what is important.
Thanks,
John

[martin manning]

Don't end bells have to be made of ferrous material to function as effective shields?

No as long as there is some other internal shield. I have a couple of options here. One would be to use one of the shielding paints internally or two there are several shielding films.

Those kinds of shields won't keep the magnetic field confined though, will they?

[Structo]

Cool!

Custom Billet Endbells!

Martin I have an old Hammond amp that the PT has aluminum end bells or in this case it's a lay down but the top cover is aluminum that I polished to a high luster so not sure if it has to be ferrous to shield.
Originally Hammond paints them silver.
It does have the copper flux band around the core.

I suppose it would the same as a sheet alumuinum cover for a chassis.

[jcsb]

Don't end bells have to be made of ferrous material to function as effective shields?

No as long as there is some other internal shield. I have a couple of options here. One would be to use one of the shielding paints internally or two there are several shielding films.

Those kinds of shields won't keep the magnetic field confined though, will they?

It is designed for blocking EMI & RFI the same as MuMetal, with much higher capacity to absorb. It is a composite that is made of copper/alloy 49/copper material. It is .014" thick and easily fabricated.

John