Friday, January 23, 2009

de-constructing the liquadora

Being totally clueless about bike maintenance is turning out to be advantageous. The first reason is that it there is no redundancy, its all new, its all exciting, its all learning. The second, more important, reason is that the highly skilled handy-persons are constantly working on bikes, leaving only me free to work on other projects, i.e. the bicimaquinas.

As i discovered during our brainstorming session with Rubin, the volunteer coordinator, Maya Pedal is not particularly well run. Carlos and Johanna are amazing and sweet, but apparently they have very little business sense. And, unfortunately, the bicimaquinas are not donated to indigenous farmers as i had thought. They are sold a little over material cost (which means they lose about 1000 of their local currency on labor). It was dissapointing to learn this, though it provided a good impetus for us volunteers to begin envisioning cost saving measures. Will is beginning to work on a model that would require less materials and work and hook up to an existing bike, instead building it all. Its a very exciting design, and there will be more about it as he progresses.

Beth suggested that the liquadora could be an add on to the rear of an existing bicycle, sitting on top of a rear rack. This got me thinking and tinkering.

I decided that the best way to understand the liquadora, by far the simplest of the bicimaquinas, was to take it apart and rebuild it.
So I did.



Here you can see that the blender turns, not by a gear, but by the friction of a rubber cog against the rubber of the tire.



An upclose view of the parts.


How it connects up through to the blender



A little closer


Here is the main part with the rubber off.



And here it is broken down even further.

I could recognize some of what i was looking at, but i lacked the language to describe what i was seeing, Beth helped me there:

The big silver part standing up is a hub, it comes from the inside of the front wheel, its the place where all of the spokes meet in the center.

The long bolt is a rear hub bolt (there may be a different name for it that im blanking on) But basically this bolt comes from the inside of the rear wheel, and beacuse it is long enough to accomadate the cogset, or casette, it can handle the rubber piece needed for the blender.

The rest of it goes as follows, the two gunky looking rings are bearings housed inside of bearing cages. The object to the upper right of the rings is a cone, its what screws onto the bolt to hold the bearings in place. To the left there is the one removed nut (the other nut and cone are still on the bolt). And the rubber comes from old tractor tire.
I love how they use materials here


This bolt is deceptive. At first i thought the square end was part of it, but anyone who knows about bikes would catch that this cannot be. No, Carlos ground down the end into a near-perfect square to fit into the blender. Man, he is good.

I then took some time to clean up the pieces, using gasoline, which i love the smell of. Ironic, i know. And then i carefully regreased the whole thing and put it back together. Tightening it was tricky because each additional part that you put on changes the previous parts you just tightened. And you dont want it to be too tight, otherwise the thing wont spin, or at least not very well. Getting it just right involves some patient fine-tuning.


This is roughly what the placement would be of the part on a rear rack. Of course there´d be some sort of plywood or something, plus it would have to be touching the wheel to work, but this gives an idea of placement.

After i was finished, i put the liquidora back together completely. The cleaning and greasing seemed to help it run a little more smoothly. I joked with Carlos that i made it better because i am awesome, he gave me a look, and i admitted it was just the regreasing.

I asked Carlos about the possibility of me making one to work on a rear rack. He said that he had designed one before and that he´d be happy to help me. He´s pretty busy, what with the expanding flower for tomorrow´s village festival, but when things calm down a little he´ll show me how. Lets hope it fits in my carry-on.

No comments: