New Springs

A project log for Hand Drive

A wheelchair attachment that allows any wheelchair to be powered in a rowing motion. It is 3D printable, open source, and available to all.

kate-reedKate Reed 08/14/2015 at 18:180 Comments

The new springs came in. They are the same as the steel springs only less intense. We had to remodel our mechanism to take into account the new springiness and angles of the springs. We found that it was faster to just 3D print the pieces extruded from the base rather than print the whole base again and again. We used laser cut wood to replace the base in our prototyping.

We also redesigned the spider attachment for the wheelchair. We made it so it uses less material but still has the same structural integrity.


We added double sided tape to our gear to soften the sound of the ratchet. The lighter spring makes the system a little quieter, but the double tape seals the deal.

We are still chugging right along, and making progress. We are closing in on the details. Almost done!