Tinkering School

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Obsta-ball - Day 2 - Week 5 (SF Day Camp)

Obsta-ball (2019), San Francisco Day CampRuby Harrison-ClayComment

After our first full day of building, each obstacle ball challenge is even more complex than we anticipated during yesterday afternoon’s preliminary design session! With more time to experiment and re-iterate ideas, pieces are beginning to fall into place.

We began the day with an engineering challenge, offered by our Collaborators Aili and Derrick. In Opening Circle, we spent some time learning about and observing the functionality of a fulcrum and a lever. Demonstrating this with a makeshift see-saw, Aili and Derrick explained how to use force to move a lever on a fulcrum (a.k.a. “pivot or tipping point”). They asked tinkerers to ponder how to use a fulcrum and lever to most easily lift a Collaborator – where should force be applied, and where should the Collaborator be placed, in relation to the fulcrum?


Next we moved into our morning design sessions, slowing down just enough to collectively decide what tasks need to be completed to build our grand projects, and who on the team will complete each task! After each group was able to check-in and re-orient, we moved into building.

Our human-sized foosball team made progress building the 24x8 ft. frame which will be the stage for the game. They definitely are accomplishing our tinkering goal of building something bigger than ourselves, particularly because each moment of attaching beams requires more than one tinkerer!


To address the question of how real-life humans will become the actual foosball pieces, tinkerers envisioned long benches that hang down from beams going across the top of the frame, or field so to speak.

What remains is the challenge of outside players moving and controlling the foosball pieces. These innovative and creative tinkerers are playing with wheels and other rolling mechanisms to reduce the friction that will be caused by the weight of benches and multiple humans.

Some of the tinkerers also designed and began building a ladder to reach the top of the frame.

The labyrinth team meanwhile took a lot of creative liberty with designing their labyrinth, and is working on a 3-tiered maze game!


Two tiers are simultaneously hanging from a larger frame, to be controlled via pulleys, and one tier sits on the ground with side knobs to enact it’s tilting motion. The ball must be maneuvered through each tier one after another. Today, the team added an observation tower – because the top two tiers are above eye-level of both spectators and those controlling the pulleys, a tinkerer will sit on an observation deck for each level to direct the pulley-controllers! Designing the mazes has been a lot of fun.

Our mini-golf came is everything but mini. The group split into many subgroups, working on varying different obstacles within their “city” theme. The first hole is taking on different aspects of San Francisco, and the group hopes to design Paris and London themed holes next.


The cable car is taking shape, with tinkerers utilizing wooden dowels to emulate the particular design of our beloved San Francisco cable cars. Those working on the Golden Gate Bridge spent the day working on the two towers, and plan to use paracord to re-create the suspension cables on the actual bridge.

At Closing Circle, we revisited the question posed by Aili and Derrick this morning by experimenting with different placements for a Collaborator (the load) in relation to applied downward force. Collectively, we decided that the easiest way to lift weight using a lever would be placing the weight or load on the lever closest to the location of the fulcrum, and applying the force furthest from the fulcrum.


We are all feeling invigorated by the scope of the projects this week, and anticipate a fun Friday showcase when we get to interact with the bigger-than-life-size obsta-ball games we are creating!

For more photos from today, check out our Flickr page!

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