Tricumbent-Hybrid
Electric Recumbent Trike - Part 2 ...
May 2007
Where
Part #1 left off The motor mount was fitted and
the basic electronics were bench tested to make sure that everything was at
least in working order...
Rather
than cast and machine another gear hub I opted to use the drive gear from the Raleigh
3-speed that provided the rear wheel assy.
The
gearing is 35 (Drive) : 46 (Driven) teeth, so that's approx 25% lower gearing
than I calculated using the spread sheet.
I
taped a magnet onto the wheel and hooked-up a digital bicycle computer.
The
rear wheel spins at 16km/h in first gear and 22km/h in 3rd.
The
motor, gears, chains and wheel were removed and the frame was moved back out to
the foundry/welding shop.
I
opted to use the much maligned seat frame from the previous post after all... It
was cut into 2 halves lengthwise with a 1 3/4" hole-saw.
It
took a morning of positioning, cutting and welding to get to this point...
This
is a view of the front wheel assembly (Upside-Down)...
The
diagonal center support between the cross beam and the main boom took a lot of
the bounce out of the frame.
This
is the Right-Side-Up view with the seat frame meeting with the top cross beams.
I
fucked-up when I cut the seat in half, as it is literally welded to the center
of the main boom. In retrospect I would have wanted it to be flush with the top.
I'll
add some pine spacers to keep the seat level when screwed into place.
It's
hard to see clearly, but a length of angle iron is also welded along the bottom
of the boom to act as a skidplate/stiffener as well.
The
angle iron runs the length of the seat and meets with the front diagonal
support.
The
completed frame doesn't look quite as bad as thought it would at this point.
I
even added a 7" gusset of 1 3/4" tubing between the main boom and the
rear frame. (barely visible just behind the seat.)
The
next step was mocking-up the front axel and steering head assemblies.
I'm
getting more used to the MIG welder and can pop pieces into place a lot quicker
than last week.
The
tack welds shown are just for getting the basic placement between the wheels and
ensuring that they are perpendicular to the ground.
The
head tubes are slightly angled inward.
"And
what were once twain, and are now joined in holy union, let no man put
asunder..."
Not
pretty, but there is lots of metal slathered on... It's like the old saying,
"If you don't know knots, do lots"
Nothing
is getting greased at this point, but there is a splash of oil on the bearings
and any accumulated rust has been removed.
This
is my first look at the trike with the front wheels installed...
I'm
kind of indifferent to it, I just couldn't put my finger on what was wrong.
Until
a buddy showed up and we were joking that there was enough room under the seat
that a case of beer could fit there.
I
started to think about how I could revise my plans and actually mount the
batteries under there.
There
was another afternoon of pulling various bikes out and checking parts, with more
measuring cutting and welding to mock-up these funky steering bars.
Again
the tacks are just to hold it together long enough that I can fabricate both the
left and right assemblies as mirror images of each other while on the trike.
Like
the lower wheel mount assembly, all the seams are carefully welded over, ground
down and welded with a wider stitch bead, ground again and built-up with a thick
final pass of the welder.
There
are lots of things that can go wrong with this trike, but I'm positive that it
won't be these pieces breaking.
The
tiller like handles that I'll steer with were from a real odd-ball bike that was
at the very back of the pile.
The
black pipes that are mounted perpendicular to the handle bars are a 2nd set of
handle bars cut from a generic mountain bike. They will be the support for
mounting a set of caliper brakes over the wheels.
I
really don't like it now, I don't care if I can carry a cooler and a suitcase
under the seat it just looks lame... Even Bruno (the black dog to the upper
right) thinks it has a goofy look to it...
The
only good that has come of this is that I can see that I'll have to place a
diagonal support across the 2 rectangles that form the rear frame from the
picture above.
During
the previous night, I unloaded the images from the camera and browsed the
pictures of the day's progress with disgust.
That
night I tossed and turned through the night as I had a nightmare that every time
I went to built something it would come out all fucked-up and useless... and I'd
have to drive these disproportioned non-linear monstrosities around town with
people pointing and laughing...
So
the next day, I woke-up, had a quick coffee and lopped-off the front-end
before 7:30AM.
The
new supports are 3/16th" walled 1 1/4" tube that is nickel plated. I
had concerns that it was solid stainless, but there was a slight coat of rust
inside the tube.
The
tube are set @ 40 degrees and well fixed to the lower support and frame.
I
made the wooden protractor a few months ago for just this sort of project.
The
head tubes were cut out from the previous cross members, and prepped for the
single upright tubes.
The
uprights were measured for level (relative to each other) and notched with a
cutting disk to hold the head tubes.
The
heads are angled inward 6 degrees and slightly back 6 degrees, this placement
points the axis of rotation in line with where the tire contacts the ground
(when steered straight).
The
steering knuckles are fabricated from a pair of handle bar extensions (from a
5th or 6th bike, I've lost count), and the tie rod is made from length of
electric fence post.
The
5/16th" stock is notched to hold a short length of 1" by 1/8th"
flat stock that is drilled out to just over 1/4".
A
1/4" bolt is welded through the steering knuckle and will have 2 nuts
cinched tight to hold the rod in place.
Later
next week I'll clean up the welds and weld one of the knuckles to the steering
assembly, while the other will be just clamped by it's original hardware, incase
I have to make alignments later. (As there is no adjustment on the tie-rod
itself)
Now
that's more like what I saw in my head earlier on.
The
frame has a slight downward kant and the lower center support may be just a bit
closer to the ground than I envisioned, but it's a quantum improvement over the
last set-up.
For
the next block of time that I can find, I hope to mount the brakes, re-enforce
the rear frame, mount some storage for the batteries, install the basic
electronics and take it for a test ride.
In
closing I think I'll sleep well tonight.