Chassis metal advantages/disadvantages?

[bereanbill]

Ok...gearing up for my next build. I'm going a step further in DIY by bending my own chassis and was wondering about materials to use? I have heard somewhere that aluminum was superior to steel because it's lack of magnetic properties. True or false? My four options metal wise are steel, stainless, aluminum, or copper. What, if any, effect does gauging have on chassis...aside from maybe workability ? Each build I do, I intend to go a step further...maybe someday I'll wind a tranny, who knows.
Thanks for all of your collective coddling. I have learned quite a bit in the short time I have been on this site.

[SY]

Aluminum is indeed nonmagnetic and a heck of a lot easier to machine than stainless steel (also nonmagnetic).

One neat trick is to use perf aluminum as a top plate- plenty of ventilation that way.

One other trick is to put the conventional chassis out of your mind, then wander around a kitchen/restaurant supply store for inspiration and materials.

[bereanbill]

Funny you should say that, SY...I have seen one particularly creative builder on ebay who uses cake pans. Think the missus would get mad if I used her Calphalon ? Platinum would make an awesome chassis, no?

[bereanbill]

So, what is the benefit of a non-magnetic chassis...or the drawbacks of a magnetic chassis for that matter?

[SY]

As a practical matter, I haven't seen any hard data showing the superiority of a good build on different material chasses (if there is such data, I'd love to see it)

A magnetic steel chassis will have theoretical challenges from the potential increase in inductance of nearby leads, inductive coupling of hum fields from transformers and high current feeds (especially AC heaters). These can be worked around in the mechanical design, but unquestionably, aluminum is more forgiving.

[Rob11966]

There is a whole thread here on aluminium vs steel -

Aluminium vs steel chassis

Rob

[Steve Eddy]

Originally posted by SY ...inductive coupling of hum fields from transformers and high current feeds (especially AC heaters).

Shouldn't steel in fact SHIELD against such hum fields?

se

[Wavebourn]

Originally posted by SY

One neat trick is to use perf aluminum as a top plate- plenty of ventilation that way.

Here is the example:

[jackinnj]

Originally posted by Steve Eddy


Shouldn't steel in fact SHIELD against such hum fields?

se

Yeah but, no but... (for fans of Vicky on Little Britain)

I don't know if it's the case now, but the folks who make mu-shield pleaded with folks to cut up an aluminum beverage can before using square feet of their stuff.

For my money, there is nothing which is superior to a piece of PCB material and mounting your components dead-bug style. It's probably superior to the FR4 PCB stuff we use as air is a superior dielectric. Ugly, but superior functionality.

[Wavebourn]

Originally posted by Steve Eddy


Shouldn't steel in fact SHIELD against such hum fields?

Does the steel SHIELD windings of a transformer one from other?