Bob Engelhardt wrote:
I just made a 2-MOTE (MOT electromagnet) brake as an evaluation of the
idea:

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I made it small to keep the time, effort, and materials small. But it
has an 8-1/2" capacity, which would be enough for a lot of the stuff I
do (e.g. electronics project boxes).

Unfortunately the results are very disappointing. I ran the MOTE's on
250v (AC into the bridge) and could not quite finish the bend on .040
(about 20 ga) steel. 18ga (.050) started, but only got to about 45
degrees before the clamping bar started sliding back. .030 bent very
nicely and although too light for a lot of stuff, boxes in that guage
would be useful.

So I have definitely ruled out MOTE's for the 24 inch brake that I'd
like to make. I'll be thinking about what it would take to wind the coil
for that. I expect that it would be painful, but the challenge would be
interesting.

BRAVO Bob! I love this stuff! (And I don't often shout.)

http://home.comcast.net/~bobengelhardt/MOTEbrake.jpg

1) It did occur to me that the line between the center of your
hinge and the gap between the clamping leaf and bending leaf
appears off - center a bit, which would cause the workpiece
to be lifted unnecessarily.

See how Dave used a *piano* hinge? Kewl!
http://www.ch601.org/tools/bendbrake/brakeplans.pdf

2) Can you use a permanent magnet to be sure your MOTEs are
indeed out-of phase magnetically? (With your head *out*
of the path of the magnet, preferably!)

3) As practice for the next design, would you consider removing
both of your windings, welding both your cores together and
providing a rectangular winding that encloses both center
legs?

--Winston