copper crisis?

These are cool:

lørdag den 16. juli 2022 kl. 16.15.34 UTC+2 skrev snipped-for-privacy@highlandsniptechnology.com:

soft wire and constraint it from bending any other way than you want it to

We use 48v as the prime DC power in some of our products, starting with a kilowatt of MeanWell boxed power supply or a Phihong wart.

SRH05S12 is a cool little part. I have some test data.

Are there electrostatic motor clocks? Cool. One could maybe make a million RPM electrostatic motor just for fun.

Yeah, 48 is great.

There are plenty of diamons. For a long time the DeBeers have had a strangle hold on them. Almost all diamonds worth anything had to go through them. They only let so many out to keep the price up.

lørdag den 16. juli 2022 kl. 17.18.32 UTC+2 skrev Ralph Mowery:

and convinced people that "used" diamonds are not good enough, you have to get a new one

I doubt people would mine the moon/asteroids for gold, they might for copper if it got too expensive on Earth. You'd need Heinlein's shipping method to make it worth while - and copper can be pushed in a magnetic accelerator...

John :-#)#

Wire drawing takes multiple passes, with annealing and capstans between the dies, to eventually neck down a rod to wire. A big hydraulic press can instantly stamp sheet into complex shapes, as evidenced by each old solid-copper one cent coin. The windings look like stampings.

That is a cool video ! We use flat wire just about like that.

I had wondered how they did that. Not that hard to do evidently.

I love the way they make woven/braided wire (Litz) and woven rope.

boB

One could use the Heinlein method to create very high grade deposits in the middle of the Sonoran Desert, say--let the rocks slow the payloads down, and then use mining methods to get the metal out. Of course it would flunk its environmental impact audit on account of all the NOx the re-entry would generate, and all the fine rock dust it would put in the air.

"This rock contains substances known to the State of California to be unhealthy if it hits you at hypersonic speed."

Cheers

Phil Hobbs

I was speculating randomly on why we have clumps of cool stuff to dig up, instead of uniform basalt. Some things were separated by local processes, coal and salt for instance, but did critters make gold nuggets and metallic iron?

If gold arrived by asteroid, why are there gold asteroids?

On a sunny day (Fri, 15 Jul 2022 08:09:50 -0700) it happened snipped-for-privacy@highlandsniptechnology.com wrote in snipped-for-privacy@4ax.com:

Sup[p]er conductors come to mind, but cooling is hard Gold price in USD is dropping, gold is s good conductor. Horses... :-) Horses are green but full of s*it.

Remember that physics question if a car driven by a propellor in the wind can go faster than the wind?

On a sunny day (Fri, 15 Jul 2022 11:49:11 -0700 (PDT)) it happened whit3rd snipped-for-privacy@gmail.com wrote in snipped-for-privacy@googlegroups.com:

I wonder with high frequency transformers if the skin effect would make some other metal than copper coated with say gold a solution.

Aren't copper tubes, optionally water cooled, use in transmitters? Anything below skin depth is a waste of copper.

My Pockels Cell driver fried several commercial inductors technically operating within their specs, from skin and proximity effects. Had to wind my own.

On Sunday, 17 July 2022 at 10:36:20 UTC-7, snipped-for-privacy@highlandsniptechnology.com wrote: ...

...

Please see section 1.6 in the Art of Electronics - The x-Chapters for how to minimize skin effects in large power cables where the skin effect is significant even at 50/60Hz.

Litz cable has traditionally been used up to ~1-2Mhz to reduce skin-effect. Above that frequency the inter-conductor capacitance reduces the advantage.

kw

Mostly hydrothermal AFAIK.

Cheers

Phil Hobbs

A traditional approach is to silver-plate the copper. Silver is cheaper than gold too.

Joe Gwinn

At microwave frequencies plated silver often has worse conductivity than copper. The surface finish of the plating tends to be irregular which increases the length of the surface.

John