I made this set of plates in about 15 minutes at the shop I'm interning
at. They are made of some scrap metal laying around the yard. It's
around 3/8-1/2" thick. They have ~15/32" holes punched for the axle, and
hang down about 2" from the center of the hole. I rounded the corners of
everything on my bench grinder at home, and cleaned off some of the rust
with a wire wheel on my bench grinder.
They are about 4.5" wide (bend-to-outside edge) and 3" long (front to
back). There is around 3/4" of plate above the hole. I essentially
modeled the plates after a pedal I had laying around.
The tools I used were, in order of importance:
Ironworker, used to cut the steel, punch the holes, and make the bends.
Cost of tool: $1500-20,000 new. $500-2,000 used, but very rare.
Square, used to check angle of bend in plates. Cost of tool: $10-80 new,
$5-50 used.
Bench grinder, used to clean off rust and round sharp corners. Cost of
tool: $50-300 new. $10-$50 used. I got mine at a flea market for really
cheap. You can also use an angle grinder. They are about the same
cost.
Welding/**** chisel/hammer, used to remove **** from a previous
oxy-acetalene cut.
You can make your own BC plates with ther tools above (the bench grinder
and **** chisel/hammer aren't absolutely6 neccessary). I would ask
around local metalshops to see if any of them will let you learn to use
their ironworker. Otherwise you will have to find someone who will let
you use their MIG welder. This will be harder to use, since it isn't
easy to keep the plates at a 90 degree angle. The drilling will have to
be done on a mill or heavy duty drill press, which takes far longer. The
ironworker will punch the holes in about 3 seconds, with about 30
seconds of setup, while a mill will drill the holes in about 1 minutes
with about 3 minutes of setup. The bends can be done on an ironworker in
about 2 seconds, and setup takes around 15 seconds. Welding instead will
take around 30 seconds to weld the material, with about 5 minutes to set
it up. The ironworker will cut the steel in about 1 second, with about 5
seconds of setup.
Basically, ironworkers (yes, it's a machine. it uses a hydraulic ram to
press a shear, bender, and punch down. They have strengths ranging from
15 to 200 tons) are the best way, but other ways will work.
I reccomend steel for ease of working, but aluminum is better for
weight. Don't go thinner than 3/8". If the bends can be done in the
metal with a bvench vise, then it's too weak, IMHO.
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"Democracy is just a word when the people are starving"-Immortal
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