When I built the red bike I had plans for a design
built the usual way with metal tubing but didn’t want to
get into welding and all that. Then I saw Steve’s bike
on the web and the lights suddenly went on.
I had already started collecting yard sale bikes to
experiment on so I cut the rear triangle off an old 26
inch street bike, a bottom bracket shell and partial
seat tube from another, and the head tube with forks off
an old BMX bike. I laid them down on an old sheet of ¾
in. Plywood in the position and angle of the plans and
just drew lines between them in what looked like a
sturdy enough wooden frame that would overlap the
tubing. Once it was cut out I flipped it, traced it and
cut out another one. After that I used my drill and one
inch drum sander to carve out half circular grooves in
both forms to hold the tubing, and bolted them together
with the bike parts sandwiched inside. I made the seat
out of two small sheets of ¼ in. ply covered with foam
and naugahyde. That’s the short version.
Like I said the whole thing is bolted together. There’s
a short section of bottom tube on the rear triangle and
short sections of top and bottom tubing left on the head
tube. All three have bolts through them to keep the
wood together and the bike parts straight. It came out
kind of heavy with the solid wood, cheap frames, and
about six bolts. I changed the seat several times and
finally cut the frame down to recline it more.
It rode really nice. I was surprised since I really
kind of “winged” it but I had managed to get the
geometry just right in spite of everything. It had only
twelve speeds and old center pull brakes but I started
riding it to work in the spring (about 26 miles round
trip) and enjoyed it immensely. I’d commuted on a bike
for about twenty years and was about to give it up
because of aches and pains when I discovered recumbents.
The red bike was a revelation. It was fun again.
After a few weeks I added a higher back rest on the seat
and a red choroplast windshield a kind of half fairing-
and what a difference it made. It was slow up the hills
but just flew down them and I never went unnoticed by
motorists.
So, after a year of bombing around town on “that weird
red bike” as it was called, I decided to try a SWB
version and actually do some design work on it. It
turned out even better. A wood working friend of mine
told me that a hollow box would be just as strong as the
sold slabs of wood so I designed the new bike body to be
made out of four layers of ½ in., ply with the two inner
layers cut out to make hollow spaces. The first picture
shows the opposite sides glued together.
The seat is more elaborate with four sections of padded
¼ in ply glued to two ¾ in rails. It slides down over
the body and attaches with a bolt and wing nut. I found
a really nice chrome-moly mountain bike frame at the
dump to use and this time cut the seat stays off and
through-bolted them to the body. I bought the front
forks brand new with bosses for V brakes. The whole
thing is epoxy glued with no bolts this time except for
the seat, seat stays, and idler wheels. I made the tilt
back steering column from small parts and the handle
bars are cut out of an old baby swing. As you can see
from the pictures it’s as unusual looking as the red
bike but it’s lots more comfortable, more maneuverable,
and a blast to ride.
One thing to mention; I made the yellow bike out of the
½ in ply because I was afraid that thinner stock
wouldn’t have been strong enough to withstand the torque
of pedaling. On a LWB it doesn’t matter so much but on
a SWB the crank is out there on it’s own, so to speak.
It turned out more than strong enough and I realize now
that I could have used ¾ in ply for the inner two layers
cutting them out and leaving only an inch around the
outside and around the grooves for the tubing, and then
using ¼ in for the outside of the box. As long as the
outside seams were completely glued and sealed the box
would still have been plenty strong and been lighter at
that. The slanted “windows” in the body were an attempt
at lightening but could probably be made larger as well.
Ron H. February, 2003
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