Mar 2, 2015

Sandbox Backhoe Preview


Ripstik Assembly


The Ripstik was completed on the morning of February 2nd, just in time for XFair. A month later (3/2/15), I'm finally documenting the experience and realizing my delayed motors still haven't arrived!

Anyway, XFair was pretty fun. It took place in the midst of the Boston snowstorm, so I didn't even attempt to ride my deathtrap on the slick floorspace. Instead I took off the coverplates to show fair-goers how the internal mechanism worked.

photo cred: John Chow
There's still a lot of work left to do before the snows melt and before this will be rideable. My first (and only) trial run had me richocheting off walls in the MITERS hallway, for two main reasons. One, my torsion rod was too squishy to supply any meaningful force. If I placed a foot on one end of the board, I could step on and twist the other half with barely any resistance. That had to change.

Way back in freshman year, I found a slim bar extrusion of spring steel that could possibly substitute. It was too narrow to usefully put screws through, so I milled two clamps to house the bar.

original torsion bar

ripstik with new torsion bar installed



I also discovered during the trial ride that my ripstik was uncomfortably tall. Turns out when you learn how to ride on something an inch plus half shorter, anything else becomes weird. I removed the upper half of my caster assembly and merged its functions with the angle block, which took off 1/2". Maybe that will be good enough.