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A self-study in composite and laminate materials and manufacture.
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Doug Goncz Replikon Research Seven Corners, VA 22044-0394
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Hey Doug,
Nice of you to pop in once in a while, but what's this latest about, or is it just point of interest you are sharing??
Take care.
Brian Lawson, Bothwell, Ontario. XXXXXXXXXXXXXXXXXXXXXXXX
On Sat, 23 Jun 2007 16:01:27 -0700, snipped-for-privacy@alum.mit.edu wrote:

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Hi, Brian!
I am studying to laminate 1 mm thick aluminum and a Masonite or acrylic base panel for high-power circuit boards for the MOEPED, then etch the laminate with lye to form traces. Wilson Metalaminate product may do for some, but one project is more than 1000 A. A copper circuit board just won't do. These traces are 10x thicker than 4 mil copper, but are a bit less conductive.
Doug
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Hey again Doug,
WOW!!! Pretty heavy duty stuff. Can't you use PC board triggers and a heat-sink instead? For that kind of current, the shorter the path the better! I can't wrap my head around anything that carries that kind of current that isn't "stud mounted" or some sort of mechanical connect (bolt-on??), rather than on or part of a film, even 40 mils thick. Even at 40 mils it will have to be a really wide trace! And you really DO NOT want to witness a 1000 Amp "short".
How is the transportation work coming along? I haven't seen much here about it lately.
Take care.
Brian Lawson
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Woot!
This is the transportation work. I am slapping together 6 of my 16 2700 F, 2.5 V caps and a battery disconnect. I should be able to put 15V x 1000 A = 15KW into a dead short for as little as about 0.2 seconds. That's 3kJ or roughly a whack with a 30 pound sledge moving at about 75 fps. Enough to break a lock. That's the whole point of the military side of the MOEPED; you can break things, cut things, and weld things. Of course the sledge concentrates the impact, but this does have some potential.
I like the ecological aspect, too, Copper tailiings are more poisonous than aluminum. I will recycle what I generate. Ferric choride is nasty. Lye is not as bad.
I've got another two each 83F, 15 V packs for up to 45 VDC on the way, enough to give the 36 V motor a real spin during the transistion from downhill to uphill. You see, coasting downhill the motor can generate 45 to 50 V.
All the caps have aluminum terminals and aluminum bus bars are recommended. They are all stud mounted components. I have some 2 mm thick aluminum to play with, too. It's just an experiment in production engineering; what is the best way to make LOTS of 1000 A, 15 V packs? This might be it.
Doug
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Hey Doug:
Six layers of 6 oz copper = 1100 A at a 20 C rise in a 25 C ambient.
http://www.pcbco.com.au/tracecalc.html
--Winston
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How wide would that trace be?
Doug
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snipped-for-privacy@alum.mit.edu wrote:

Each of the six traces would be about 4.8" wide. Or you *could* parallel four 4/0 cables! :}
--Winston
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