Saturday, February 7, 2009

project: wheel continued

I believe when i last left off i had flipped the fork over, finished welding a new base onto it and the mill was even floppier than before. It kept falling off to the side (as you can see in above photo).

Well, i came back to it a couple of days ago with fresh eyes and tried to figure out what to change.

The first thing that i did was to switch the stem with pivot around, i hadn´t done this when i flipped the forks over. Considering that the angles of both the pivot joint and corresponding drilled holes in the neck of the fork were a little wonky, i thought it might make a difference. And it did. Though not perfect, it definitely stabilized some when i reattached the two pieces as Will made them.

It was sitting well enough that i thought i would give it a go. Palo was conviently wanting some coffee ground, so we killed two birds with one bike.

It was a little too loose at first, Carlos showed me how to tighten it and voila, Palo had delicious freshly ground coffee.

The next logical step was get the whole unit sitting lower. Although effective, it was a little ridiculous to pedal the bike by hand. Lowering the seat would allow me, and your average Guatemalan, to use leg power- a more powerful and ergonomical arrangement.

I think i mentioned it in a previous post, but if i didn´t, my first thought to get the whole unit sitting lower was to ditch the wheel, but keep the hub (the hub being the epicenter of the wheel where the spokes all attach and the axle is). My plan was to wrap the hub in rubber so that it would function like the liquadora.

The first thing to do was pop off the wheel. Next i had to remove the tire and inner tube. The air had to be let out of the tube, and then i used these little pry things to convince the tire off. I think they are called tire levers, or leveragers? Is leverager is a word. I don´t think so, but we can pretend it is.

And separated like so...

Then the spokes had to be removed using this thing- called a spoke key in spanish, i think spoke driver in english. The key is used to unscrew the spoke nipples, yes, nipples. The nipples are reverse threaded, or another way to think of it is that they are correct threaded if you view them from the inside of the rim. Like this:

Once removed, the hub looks like this. The box its sitting on top of is the nipple bin. That´s where all the nipples go, courtesy of Anneliese´s awesome organizing around the shop.

I took all of the spokes out, tedious for sure, but not nearly as tedious as removing one when the rest are still attached to the rim.

Then, just for fun, i put the hub back on to see how much lower it would be.

Pretty big difference. The seat could now sit where it should.

Seeing the hub like this gave me a thought about the rubber. What if the rubber were shaped to conform to the wheel? It would increase the surface area, and therefore pull, and it would also serve just to keep the darn thing from falling off to the side.

On the roof there is this big tractor tire, Carlos uses it for exactly this type of thing. He was fine to have us cut into, just be mindful of the metal (i didn´t know tires have metal mesh in them). We cut from the side, since it seemed to be the place with the least metal. (oh, i´m saying we and us becuase Erin has joined me at this point).

However one poor go with the drill was enough to convince Erin that there were better things to do. (She broke Carlos´homemade hole saw) I suggested she try again with a different strategy, it wasn´t her fault the bit broke, it was weak and would have happened to either one of us. But she had her power tool fill for the day. There goes we.

I cut out several circles and ground them to a flatter state. I then drilled small holes in the center of them and cut them apart so they would wrap around the hub (leatherman strikes again!)

Once on the hub they looked like this:

Alas, they didn´t work. They were just spinning in place, not moving the hub at all. They needed to be attached, and in a flash i had the perfect idea! The hub, needing to hold spokes, is lined with holes. Why don´t i drill holes through the rubber and tie wires through? That´ll do it for sure.

Well, drilling accurate holes in the rubber was pretty difficult. Really it just didn´t work at all. So in a Carlos-esque move i thought, why don´t i get a sharpened spoke red hot and just jam it through the rubber? (Something OSHA never would approve) (they never approve the fun stuff)

So i did.

In a word- awesome. Okay, two words- awesome & ineffective.

I took the whole thing mostly apart, ground down some spokes and got to it.

After way too much time of not being able to get the molten spears from one end to the other i began to consider other options. Also the stench was probablly getting to the others in the kitchen, "you´re wasting gas" they told me. Yeah yeah, you just don´t like my tire stink. Weirdo.

It took me some time, but eventually i figured out that the holes don´t actually line up. They are slightly angled from one another. Also to get the spear through it also had to hit the right height. There was enough play in the whole system that it would be pretty difficult to actually poke it in one end and get it to come out the other. To compound this, i could only come from one side as the welded-on gear was most definitely in the way. (I tried to make a right angle spear to get around this, to no avail).

Once the novelty of the crazy plumes of rubber smoke, which seemed to stick to the hub like magnents ( so cool, you gotta try it), i decided that this method wasn´t going to work. At least not without consulting the maestro. I tried to melt the rubber onto the hub some, and to a degree to the other pieces. It seemed like it worked, but a test run proved otherwise.

I reattached all of the parts to the hub, then used the metal grinder to carve out the shape of the wheel. On the bike it looked like so:

Okay, so what else can we grind? Cocoa beans!

And in action, here it is:

The mill, couldn´t be too tight (as tight as it need to be for a good grind) or it simply wouldn´t work. It functioned, but poorly. Its funny, in the video you see the chain hopping all around- turns out it wasn´t even on the gear but it still worked- i have no idea how.

Tightening up the mill would wreck the rubber set up.

And also, the chain kept getting strangely stuck. Upon examination i found that it was popping off of the chain ring on the mill and getting caught between the ring and the barriers on it. Fixing this involved some fine tuning with a wrench. The walls couldn´t be too tight or they would totally constrict the flow of the chain, but they couldn´t be too loose or the chain would fall off and get caught.

Once i got this all settled it, the rubber was still a problem. Yarrgh! If only my pyromaniacal scheme had worked.

A few days earlier i had spotted a little tire, probablly the tiniest in thewhole mess of bikes. It would be a middle ground between the rubber covered hub and the original wheel, probablly requiring the seat to come back up some. I´ll give it a go, but its already ripe with new challenges, namely that ther are no inner tubes its size- i´ll have to construct one manually.

I may just scrap the whole tire, rubber bit entirely. Plan C is already stewing in my mind, though i don´t think its a design a north americans will like. Yet.

The new tire compared to the previous one.

Thursday, February 5, 2009

a late night dash to the middle of nowhere

At 11:30 am yesterday, Palo (or Chris), comes huffing up to the interent cafe. "Carlos says we´re leaving right now for San Marcos" "Right now?" "Yes, right now." I close my session and we both scuttle up to the shop.

Sure enough, as we arrive the first big cement hunk of the bici-bomba is being loaded into a white truck. We jump in and get the rest settled.

Without enough room in the cab, three of us are puzzle pieced into the assortment of objects occupying the truck bed. Chris seems to have a better sense of what´s going on, here´s what i find out:

1. We´re going to San Marcos, neither of us know where that is, but its apparently 6 hours away.

2. We´re going there to set up the bici-bomba (bike water pump) and we´ll be staying over night, probally installing early in the morning.

3. After the installation Carlos, Palo and I will get on a bus and do the six hours back.

4. Palo doesn´t think they are going to want to stop for lunch. Supposedly we´re already late.

So we bump our way out of town, Palo and i are pretty stoked to be riding Guatemalan style, the view is beautiful and the fresh air feels great. Its also alot more social as everyone wants to wave to you, and well, we wanted to wave to everyone.

Despite the beautiful sunny day, the wind didn´t take to long to trick us into thinking it wasn´t quite so beauftiful after all. We got pretty cold pretty fast. Luckily i happened to have a pair of work gloves in my pocket and Palo lent me his sweet dreadlock soaked ski mask, which actually wasn´t smelly at all and was so so wonderfully warm.

Though after while even the gloves and mask weren´t doing it. We didn´t have much of a choice til fate intervened. At some point a couple hours into the trip traffic just stopped. To us gringos it wasn´t entirely apparent what was going on, but we soon found out it was construction. You know in the states when the neon-green reflector suited men stand in the middle of the road with their revolving Stop/Slow signs? We got caught in the Guatemalan equivalent. Instead of waiting for six and a half minutes, we waited for over a half hour. Great chance to pee. Great chance to watch Grey´s Anatomy.

Actually i´m not giving it enough credit. It was far more enjoyable than it would have been in the states, everyone expected a long wait and turned off their cars. People got out and socialized, and of course, there were vendors galore. I bought gum, which turned out to be an excellent investment for the trip.

Oh, but i digress, what i meant to say was that i pulled out a long sleeve shirt that i had stuffed in my sleeping bag, and Carlos lent me his sweater on top of that. "Now i´m golden" i thought. A few more hours convinced me otherwise. Our next pee break provided the opportunity to pull out the last stop- i wrapped myself in my sleeping bag. And it was glorious. I even fell asleep.

Pretty much when i woke up we were on our last leg of the trip, off the highway and onto a very windy, very dusty, jostling, heart-burn inducing road. At this point Palo and i were past hour number five. The other guy with us in the back had moved into the cab, and who knows where the other guy went? (Palo says he hopped on a motorcyle at one of our pee breaks...) He and i decided that pretty much any other form of transport would feel luxurious in comparison. Yes, even the tightly packed chicken bus would be a step up. We were ready for our home-made roller coaster ride to be over.

By dark we pulled into a small farm off of the country road. Having stopped several times before we weren´t convinced this was it, but a "baja" from Carlos said that it was. We start pulling stuff out and Carlos, known for his joking, says, "he wants us to set this up tonight." Haha Carlos, thats a real knee slapper right there.

He wasn´t joking. We carried the cement blocks down a small hill, through a bunch of brush and to an old fashioned stone well. The roof over top fit the locals, but I, and Palo especially, defintely didn´t fit. Before long we were ripping it off, not becuase Palo is the tallest person currently in Guatemala, but because the pump needed the overhead space.

The owner´s sons (and sons´friends?) pulled out two wooden stakes along side of the well and flattened the surrounding earth to make room for the bike piece of the pump. Once ready we slid the cement into place. Next we put the corresponding cement piece on top of the well. Carlos seemed skeptical about the angles, but we moved forward (usually the pump and bike are level with one another).

Meanwhile Carlos is untangling the rope and beads, and the owner is measuring the distance to the bottom of the well. He checks his length against Carlos´PVC that he brought, and there is more than enough. The PVC is cut and the rope fed through it.

Next the flywheel (the tire pieces cemented together) is attached to the pump section and the chains are installed between bike, flywheel and flywheel holder. The pump is assembled in pieces and slowly put into place. Everyone is working on something, so most things are simulataneous and a little hard to keep track of. Eventually all of the piping is installed and Carlos begins to feed the rope and beads through the system. When he gets to the end of the line he ties it off to itself, and we spend some time biking it and testing its taughtness. It needs to be cut and re-tied several times. (Any excuse to pull out my leatherman is a good one.)

The line of the rope was confusing to me at first, and honestly looked like it was going to catch on its itself in a few spots. But Carlos knows his stuff, it worked great. Toward the top excess water spitted onto curious onlookers, but it was nothing compared with the thick flow pouring out into a 55 gallon drum several feet away. I was designated official pedaler for the evening and i was surprised to find how little effort it took. The pace was somewhat awkward (because the beads do stick a little bit) but otherwise it greatly simplfied their former one-pail-at-a-time operation. And, beyond construction and transportation, with absolutely no fossil fuels. Just feet.

Not to long after our installation, or maybe it was in the middle of it, Carlos announces that we are going to catch a 2:00 am bus, no es broma he says (not a joke). With his constant barrage of jokes we´re not sure what to expect. I think this is part of his plan.

We finish up and Carlos says, okay ready to go? We are going to walk for three hours to the bus stop and then get on the 2:00 am bus. We start walking joined by one of the owner´s sons (or sons friends, its really not clear). The long night aside, the moment is beautiful. Without any light pollution we are greeted by a crystalline sky. Though we have flashlights, the moon is more than bright enough to light our way. Silent and cool the night is inviting and fresh like springtime in the states. On dirt road and foot path we make our way through the quiet hills.

Carlos insisted I take this picture even though i told him it wouldn´t turn out well. These are the only lights in the area, a mining operation on the other side of the valley.

45 minutes later we walk into dowtown San Marcos, a town about an eighth the size of Itzapa. This is where we are to catch the bus. I´m glad he was joking about the three hours of walking. I´m glad he also, as it turned out, was joking about the 2:00 am bus, though we did catch a bus right before day break. The guy who was with us, Hector i think, he had some sort of quasi-apartment, which was really more like a dorm room. No kitchen, no bath. Not really sure how that works. It was awesome of him to put us up and to be our guide. Though i´m conviced Carlos is secretly James Bond and could have gotten us back entirely on his own.

After many more hours of sleeping poorly through three separate bus rides, we finally did make it back to Itzapa. Carlos told us to take the day off. Which was kind of funny considering how few bikes we actually service on a daily basis. Really, he needed the day off and he deserves it. Carlos works really hard.

Tuesday, February 3, 2009

The bici-bomba

For as long as i´ve been here there has been, what i thought was a broken, bici-bomba (bicycle-water pump) sitting off in a dark corner of the shop. Yesterday we pulled it out and started making new parts for it.

First, Anneliese and i dragged these two heavy pieces out into the light to clean them off.

Then Carlos instructed me to use my knife to cut the sides off of two tires. Erin walked by while i was doing it and asked to join in. The next part, Carlos showed me, was to clamp the pieces together, drill holes in them and then use wire to tie the two pieces together.

When i went out to decorate the town, Erin took over

Meanwhile, Palo, or Chris, looked for the perfect bike wheel to fit inbetween the tire pieces. He found one and later wired it to the inside of the tires.

Fast forward through the evening and we pick up this morning with Carlos mixing cement in the road. Its an interesting process to watch, he pours a mound of cement mix then depresses a cavity in the center. In the cavity he pours water and then skillfully directs the water through all of the mix with a flat shovel.

Once the cement was mixed Carlos shoveled it into the reconstructed-tire-bike-wheel. The wheel was sitting a top a flat board with a hole drilled out (for the axel to poke through and remain un-cemented).

Next Palo twisted some thick metal wire around a piece of PVC, which will evidently hold the PVC in some way. Carlos welded the metal rings that Palo made to two pieces of rebar and then fit them onto the PVC. He then fiddled around with them in relation to a much larger piece, then left them there, standing up and calling it a day.

I believe that the way that the bici-bomba will work is by pulling a long string with a series of wooden beads on it. The beads are forced under ground into the water source, then pulled back up through a narrow pipe. In this way each bead acts as a shelf for a small amount of water, and in total it can lift a fair amount over time. The picture at the very top of my blog, where the title and other pictures are, of a man on a bike, that one, that is the bici-bomba in action. It looks like a pretty exciting device- we are all really looking forward to getting it installed and functioning.

Today in the shop, we were unusally busy. Lots of folks came in looking to have their bikes fixed, and all of this in addition to the bomba work. It was good learning all around. I was very excited to work on my very first bike, as opposed to shadowing someone while they worked. Though i did need Palo and Anneliese to explain a few things and lend a hand every so often. The problem was that his crank arms were flopping around (the parts where the pedals meet the body of the bike). I took the crank arms off and the bottom bracket apart, it really needed some cleaning and replacing of a few key parts. We tightened it up and it spun beautifully. Mission success!

Anneliese got to work on a sweet old Schwinn, complete with bike powered head light and spedometer! It was a beautiful, albeit rusty, piece of machinery. We all spent some time oggling at it.

Anneliese removing the seized chain via gigantor bolt cutters!

To clean the replacement chain, Anneliese opted to use the fire trick.