Saturday, October 9, 2010

The frame

The frame was built in two parts. Essentially it is part TIG welded aluminum tubing and part sand cast aluminum.  My reasons for doing it this way was to have the strength, serviceability and appearance that I was going for while at the same time keeping overall cost down. That said, the result was fairly heavy thanks to the sand-cast portion.  The production version will probably be some combination of stamped and stock aluminum parts TIG welded together in a jig.

The sand casting was actually two halves that were welded together. Not a single piece as shown here.

Because I am a horrible TIG welder, I enlisted the help of my friend Brian at Alloy Weld Works in the Inland Empire. When taking on these big, multi-component projects. I definitely recommend building a strong network of people willing to help. I for one wouldn't have finished the project in the required time without the help of some good friends. For more information on building your network check out the book: Tribes by Seth Godin.

Wednesday, September 1, 2010

Drive Train

The power transmission for the Cycleton One is contained in the rear swing arm. In this post I am going to explain as much as I can about the design and build processes without giving away the trade secret goodies.  I will say; however, that the motor is a custom build from Astro Flight and I was heavily inspired by this guy's electric recumbent motor set-up.

The three stage gear reduction system goes from the motor to a timing pulley, then through a jackshaft to the front sprocket and finally to the drive sprocket at the rear wheel.

The motor is fully adjustable in the mount to adjust belt tension and better alignment.
Several iterations of Masonite mock-ups were done to get the design right.
Final parts were water jet cut out of .25" aluminum and then hand milled for precision fit
A special jig was made to mill out press-fit bearing surfaces
Workin' it out
The focal point of the right side of the bike. I did run into some rubbing problems, but I think a smaller diameter timing pulley should rectify the situation.

SU2010 Grad Show sneak preview photos

What a Cycleton boutique showroom might look like
Myself and instructor for the project Bumsuk Lim
Branded Typograform chandelier
Mahogany wedges keep bike in place

The "tank"

The idea for keeping a "gas tank" form incorporated as part of the final design didn't come easily. As a designer, I usually try to ensure that everything is justified by function and this is usually reflected in form. The decision to place a volume where the gas tank usually is, came from the insight that riders expect and need to feel something substantial between their legs. The need is both a function of control in corners and to inspire overall confidence.  The form that you see today went through several tens of iterations from bare essential "knee-paddles" to more traditional forms. Finally I settled on a shape that would offer enough volume and surface area please the rider's ego and hide some electrics; yet, still be minimal and light in appearance and weight.
Tank/seat half way through clay
The process of actually building the seat and tank was long and exhausting. For the sake of staying interesting, I will try to stick to the highlights:

     1.  Build the base and pack on clay.
     2.  CNC the basic SolidWorks model into the clay.
     3.  Make changes in tape wall drawing and then on one-half of the clay.
     4.  Get help from Ryan Black-Macken with mirroring and adding a body line.

Initial hand modifications
     5.  Finalize changes in tank and mirroring.
     6.  Spray clay with magic rubber spray paint.
     7.  Make a three-part mold utilizing soft silicone surface backed by 20 min plaster.
Part sprayed with barrier and beginning to make parting line for mold
     8.  Cast multiple layers of fiberglass and carbon fiber to ensure strength.
     9.  Clean up edges with die grinder and begin Bondo work.
   10.  Enlist help of paint guru brother Antonio Yorba to tirelessly straiten wavy surfaces
          and fill pin holes.
How the lower fairing looked after removal from mold
      11.   Prime and sand at intervals of 100, 180, 240,320,400,and 600 
              (the last two being wet)..
      12.   Mask and spray interior surfaces with textured paint for
              durability and aesthetics. 
      13.   Mask and spray two tone parting lines for color graphics.
      14.   Paint is three-part base/pearl/clear.

This is pretty much where I am at now.  This still leaves a need for a way to mount the seat and tank on the frame. I have a good idea of how that will happen, and I will be posting sketches and solutions on that as it comes. 
More appropriate tank photos to come