It lives! Part 1- 11/21

November 21, 2013

Deliverable: Working Prototype

Thank you, good St. Eligius, patron saint of metal workers! Today we tested our prototype, failed miserable, fixed some things, tested again, and our design worked!

We first started the day by attaching the chainstay support to the top of our stand. The epoxy with which it was fastened didn't work, and so we resorted to duct tape and twine.

We put the bike up on the stand, and while it did not collapse, the bike did not fit in the stand. The ends of the top bar hit the gears, so the bike didn't sit flat:

We decided to quickly shorten the top bar, basically making it only as long as it absolutely needed to be.

We started to unscrew the top bar from each sides, which worked well except for one screw. Using our mighty strength we had accidentally secured it too firmly, and we couldn't unscrew it. We tried unfastening the screw and nut using a: screwdriver, wrench, hammer, metal cutter, pliers, and hand saw. This process took about 45 minutes. Finally, Amy tried to use the mini band saw we have in our lab, which didn't work. We then went to the machine shop, where Amy used the bigger band saw. She sawed through the screw, which was good, but she also incidentally welded our drilled hole shut, so we  had to drill another hole. Basically the whole ordeal ate up an hour of our time for something that should have taken approximately 10 minutes. Lesson learned: never trust your time estimates.

With our shortened top bars finally in hand we drilled new holes and reassembled the stand, complete with reattaching the two chainstay supports that had broken off during the kerfuffle. Here is our new, improved bike stand:

We tested the bikes in our classroom, and look at this magic:

Our bike stand works! It successfully holds a bike. Alex tried getting on the bike. She managed to cycle for about two seconds, enough to blend a blueberry, before the structure started to tip over and collapse. We're going to chalk that up to our necessitated screw joints, and when we weld the structure it will be more supported and less likely to buck off the rider.

We talked over our design and looked at things we could improve. On Monday we're going to talk to Larry about the following ideas:

-Completely eliminating the top bar, and having the two side bars reach up and be welded to the chainstay supports.
-Changing our adjustment mechanism from a slitted bar and a screw to a sort of graduated stair case adjustment that would click in place, or another idea.