Some of the people who stopped by the SFT table had great input on one of my designs, and there was so much excitement about this concept that I decided to go ahead with a prototype.

The prototype pair of shoes was finished just in time for us to head to Owens Valley. Dan has been testing them all week, and he’s very happy with how they fit and the tension properties of the shoe. When we return to the shop, I’ll build a second version with some pattern updates for greater comfort and stretch management.

Checking arch shape of the shoe under load.[/caption] It's time to put the rubber patterns into CAD.

Last week was last week: we drove to Las Vegas to learn about last- and shoe-making from Ray Klose, who makes beautiful custom climbing shoes. He taught us a couple fancy tricks to make perfect lasts that we can't share, but the basic process goes as follows:

Cast a one-use material around your feet. Pour a hard plastic in the one-time mold.    

Remove the hard plastic cast. This is the basis of the custom last. Trim and adjust the last as needed. For example, I didn't do a perfect job of holding my feet in the same position, but Ray was able to adjust the left to match the right by skilled trimming and gluing. Mak and I tried to help out where an extra pair of hands was needed, but much of the artistry we just had to watch, document, and absorb.

Roughen the surface of the cast lasts and sculpt out the final shape of the shoe. For SFT, we wanted shoes that were more generic in shape that the ones Ray usually makes. This will let us share the first pairs of shoes made on these lasts with user testers who have similarly sized feet. This means that many of the peculiarities of our lasts were smoothed out so that the final shoes wouldn't be too customized for other people to wear.

Ray showed us how to make quick masking tape patterns from our lasts to check sizing. He made up a couple of slippers that we tried on. They fit like gloves! Since the lasts passed this test, Ray will begin making two pairs of shoes in our design. We'll be working with him remotely for the next week as he builds them, and then he'll ship them to us for climb testing.

Three weeks ago, we started making patterns. In order to really tackle the two most important parts of the shoe, we decided to create separate patterns for the toebox and the heel cup. After a week of iterating improvements on these patterns, we finally began putting them together. Over the course of another week, we experimented with combining the two parts of the shoe to make sure everything fit together nicely.

With one resoling kit and one salvaged sole from a previous shoe, we applied rubber to three of our prototypes, using bicycle inner tubes as rand material. On Wednesday, we finally got a chance to really test our work by going climb testing at the nearby climbing gym. We were pleasantly surprised with the sensitivity of the shoes. In some cases, the rand didn't cushion the toes enough, but bicycle tubes are about 0.8 mm thick, compared to 1.8 mm standard rand rubber which we'll use for our next prototypes.

We finished just in time to drive to Las Vegas to work with Ray!