2016-02-26 (F) Weekly Summary

Deconstruction of one bike was necessary and that was mostly done last week. Some parts still need trimming but DEconstruction is done. CONstruction was started by building a seat. The seat doesn’t really seem like the logical place to start, more of a detail, but when it comes to determining the positions of the handlebars and pedals the seat should already be in place so there is a starting point. The first attempt at a seat was PVC tubes on 1/4" (18.75mm) threaded rods. The shape was good but the rods were too flexible. Larger rods would have gotten heavy so the design was scrapped.

Failed seat materials

The next day a design was sketched out for a wooden seat and parts were purchased. The design relied on some metal parts for reinforcement but was really just a couple slabs of wood holding dowels.

Sketch for wooden seat design

Angle braces were purchased to make a seat bracket. The brackets were arranged so they would tighten on a 1/4" (20mm would work well) rod which could be clamped by the seat post.

Flat seat bracket made from angle braces

Some ordinary 1x2 lumber and dowels were purchased along with some foam padding which would fit over the dowels. The wood was all cut to length according to the sketch and the hardware was used to assemble everything into a seat that kind of looked like lawn furniture. This model was significantly stronger than the PVC version.

Wooden bike seat

Hardware for attaching the bike frames was lost so new hardware had to be purchased. Hardware for attaching the upper frame had not been purchased at all. Two analogs, things with the same diameter, were picked up around my apartment and brought to the store so I could find clamps that would fit.

Store purchases next to analogs

Purchased hardware was attached to the bike frames and fit well. The bikes frames were laid on their sides and the hardware pieces were attached so the frames could be arranged into a ridable configuration. Nothing was tightened yet.

Arrangement of hardware for attaching bike frames

The seat was attached to the bike and the pedal arrangement was checked. It fit well and was reasonably comfortable. The seat would not be suitable for long periods but it can be covered with ordinary cushions. The upper bike frame was held in place with twine for this test. Twine is not part of the final design. Shocking I know.

Sitting on bike while upper frame is suspended by twine

Attaching the old wheel sockets was not a problem but attaching the rest of the frame has proven difficult. Again, it is important to me that the frame doesn’t get drilled because holes would weaken it and considerable force may be applied through these tubes. Wide braces were purchased with the hope of connecting the frames together. This hardware didn’t work. The frames were not firm, they would wobble.

Attempt to use wide brace and cable clamp

More care will have to be taken when arranging the pedals for final installation. If the pedals are too low they will interfere with the front wheel.

Pedals will interfere with wheel

A rare unicorn picture

The rest of the weekly summaries have been arranged by date.

First time here?

Completed projects from year 1
Completed projects from year 2


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