Transformer obsevation and question - welded laminants.

[chopstuck]

I was looking around a local music store and found a Peavey Triumph Amp that had both PT and OT mounted in a stand up orientation. The thick metal mounting brackets were, (looks like factory job) welded across the laminants of both the transformers on two sides. Now isn't the theory how transformers work and maintain thier efficiency by using insulated laminants. Rusty transformers with contact along the laminants are supposed to be much less desireable due to "eddy currents" and transferring energy into heat etc.

How does Peavy do this and still build this really loud and not too terrible amp ? It was cheap and I was thinking of buying it for the parts until I saw the welding.

[Structo]

There seem to be a lot of urban myths associated with transformers.

I always read that rust was not a good thing to have on laminations but along comes Mercury Magnetics to dispel that myth.
I don't know who is correct about that.
http://www.mercurymagnetics.com/pages/mainframe.htm

Also some power transformers have that copper sheet metal flux band to control eddy currents (I think).

It's hard to figure out what is true and what is false many times in vacuum tube amps.

Here is a PDF file about NASA soldering techniques.
http://www.mercurymagnetics.com/pages/S ... ions2R.pdf