Induction, #8 or something...

I've limited breakboard projects to about 30 connections.. After that, I make disposible PCB's that get all hacked up with changes. D from BC

Ooops I mean breadboard... Must be getting high from all the chemicals I'm using on my PCB project. :) D from BC

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drives)

You've put a lot of good work in there, don't think I'd ever have the patience. Saw a 75kW version in action last week on 2 pieces of 2" shafting. Switch on and a sec later the shaft ends were glowing white hot and welded!. Took 5 seconds to quench with water. The 2.5MW unit was even more impressive. Looks like it had cornered the world's stock of transistors and Copper busbarring. john

Thanks - love to see updates on your project.

How did you cut the copper? You've got better edges than what I've done. I've used copper roof flashing, cut it with metal snips - and got ragged edges, plus the copper curled.

Ed

Thanks.

Exactly. ;)

Careful use of snips, plus a hammer and flat metal surface to bang on, files and sandpaper got that work done. If it's too hard (I started with pipe, which is a harder temper), anneal it (torch to dark red heat). If it's not flat, flatten it. If it gets too hard again, anneal again.

If you're always getting burrs and ragged edges, that sounds like you aren't continuing the cut at the root of where your last snip got. I never got good results with aviation snips, either.

YMMV, but this was done with 0.042" (give or take a few thous) stock. A little heavy for hand work, but holds its shape and doesn't take too much force to work, between bending by hand to leveraging it into place with pliers and hammers.

Tim

-- Deep Fryer: a very philosophical monk. Website:

Nice... sure you don't want a bigger fan for your radiator?

And the radiator is elevated a cm or so off the surface so the hot air can escape, yes?

Michael

Yes, yes it is. 8-)

I'll put some squirrel cages in cowling later. I have two blowers, removed from microwave ovens, that should blow reasonably. At the moment I get a comfortable temp rise at full power (dissipation under 1kW), this being at roughly 60°F ambient in the chilly basement.

Presently I'm testing at 50V, probably less than 200W. After holding the thing at resonance for some time, the circulating water gets luke warm (without fan running).

Tim

-- Deep Fryer: a very philosophical monk. Website:

Did you remove the squirrels, too?

A blowing fan will make your radiator much less efficient: the hotter the radiator the more it radiates.

Well, if you want to be perfectly pedantic, you'll have to realize that it is, in fact, an automotive air conditioning evaporator. Rather than radiating into its surroundings, it absorbed. ;)

Tim

-- Deep Fryer: a very philosophical monk. Website:

Tried, but the buggers are everywhere in this town. They'll just have to learn their lesson when I spin it up ;-)

Tim

-- Deep Fryer: a very philosophical monk. Website:

when I first moved to MA, my workmates thought I was mad as I spent my lunchbreaks feeding squirrels. they reckoned they were just rats with good PR.

Cheers Terry

I lost power to my business for half a day once, when one of the furry little bastards tried to climb down the insulator on one leg of a