Why bamboo - why a bike -
2 passions I have are fitness - primarily cycling, and well, gardening and anything that comes from the ground. In my garage you'll find bike parts and bikes in different stages of assembly/disassembly, and in my yard, palms, bamboos, flowers, oh yeah - and more palms...
Bamboo bikes are just cool. I've found a way to incorporate my passions, plus recycle unused items and come out with an end product anyone can enjoy - whether it's just looking at it or riding.
GETTING STARTED - I am just under way on this project, and will document this from the beginning with photos, so that this instructable is, hopefully anyway, easier to follow and better described than my last. Last time, I came to the instructable having finished my project, trying to go from memory, and axplain what I'd done several weeks before. This time I will update, both photos and commentary, as I go.
WHAT YOU WILL NEED
Raw Materials -
Bike frame - Aluminum, Carbon, steel, titanium, scandium, boron carbide - I've found many places to get wrecked/damaged bikes - local bike shop, yard sales, friends, in your own garage!
Bamboo - Blue Hennon (Timber Bamboo) or Thamvong (Iron Bamboo) - are thick and very strong, but several other species will work just as well, and may give you a different look. Iron Bamboo is quite a bit heavier and can be almost completely solid through it's structure. So, possibly either use Hennon for the front triangle and Thamvong for the rear stays, or figure out a way to hollow out a bit of the Iron Bamboo if you want it for the front structure as well?
Carbon string/tow - My suggestion would be to jump on eBay and do a search for Carbon Tow.You can get 3K, 6K and 12K. I probably used about 1500 - 2000 feet of carbon on the first project. 3K is the narrowest and easiest to use, but 12K seems to be cheaper and covers faster.
(Feel free to experiment here - you don't have to use carbon fiber if it is not available to you for whatever reason. I've seen palm fiber used, hemp - both cordage and raw hemp fibers, and there are others. Just be sure you have some way of tightly wrapping the joints and getting excess resin out of the joints. Extra resin left behind makes things heavy and weakens the structure substantially.)
Resin - A good resin is key to this project. I now use only West Systems epoxy resin - 105 resin with 205 (fsat) or 206(slow) hardner, depending on ambient temperature. Here again - I probably used about 1/4 gallon resin/hardner on this project - but much of it, perhaps as much as half, was wasted, and then a lot of it was sanded away.
Beware - this stuff sets up fast in the cup if you use the 205 fast cure hardner, and it's over 80 degrees F. But if you do use this, you can do several layups in a single day, which really speeds things along!
Misc. Small Parts - Things like cable stops, brake bridges, tubes if you want them - Nova Cycle Supply -http://www.cycle-frames.com/bicycle-frame-tubing/BRAZONS-SMALL-PARTS/ - Careful though with small orders - they will charge you a fee for an order under $50, just a head up!!!
Finishing Stuff - Clear coat, colored paint if you wish, wood stain (again if you wish), misc. rags, Tung Oil Finish, carnuba (car) wax - any kind, I like Meguiars Gold Class...
Misc. Bike parts - depending on what level of build you want - fixie, mountain bike, roadie, etc... But you'll definitely need a fork, headset, crankset, brakes, bars, and pedals at the very least!
Plumber's torch - for the heat treating of the Bamboo
Gram Scale - To measure accurately the resin and hardner mixture
Dremel multi-tool - This is a huge part of what I do with this project - from cutting apart the old bike frame, to sanding bits, to the final finish the Dremel Multi Tool is my main go to item!
(Note, Carbon Fiber/Fibre dust is SUPER irritating to the skin, and mucous membrains of the mouth, nose, and throat. But, also will destroy your Dremel tool! Dremels have a couple of openings where the engine sheds heat. These also are a point of entry for carbon dust to go directly into the motor. You should over these with some sort of filter, cotton face pad, something, to keep the dust out. I've been making several bikes over the last many months, and was going through about one multi-tool a month, before I decided to cover the holes.)
Die Grinder/Angle Grinder - For cutting
Sand Paper - 100 grit, 220 grit wet/dry, 600 grit wet/dry - sanding belts can really help with rounding the lugs beautifully! If you Youtube bamboo bike you can see some of the sanding techniques in action - there's a lot more information out there now, on how to build these frames, than there was when I originally wrote this.
Measuring device -Tape measure, yard/meter stick, etc...
Marking Pens- for marking cuts
Assorted Rasps and Files - round and flat
Initial step is to make sure you have all items to get started.
Once you've done that, and you have your bamboo, you can begin the heat treating process. I used the plumber's torch method.
WARNING - Make sure you punch out the nodes inside the bamboo prior to the start of heating your pieces or you'll be in for a very loud surprise - bamboo WILL EXPLODE if you do not do this! Between nodes is a pocket of air that if heated has no where to go under expansion, the build up of pressure will cause the cane to burst. It's fun, if you're face isn't right next to it, as mine was when I discovered this little secret!!! Also heating bamboo gives off a certain smell and will kind of make you sick to your stomach (me at least). Don't do this inside, do it somewhere with plenty of ventilation!
Take the torch and run it along the bamboo about 3 inches at a time while turning the bamboo slightly. You can take the bamboo to whatever color you are happy with at this point. I chose to go pretty dark, even burning the bamboo in a couple of small spots - not badly though. Don't stay in one place too long or your bamboo will burn badly or split due to uneven heating and shrinkage in that one place. Slow, smooth and easy... Use a couple of test pieces to get started, but once you get the pace down, the flow begins to make sense, and the rest is quite easy.
As others have stated, the reason for heat treating is to cook the sugars in the grass (bamboo is a grass) and carmelize them for strength and rigidity.
NOTE - Remember to go a little darker than you expect, or want, the final product - you will be sanding the canes and removing a good portion of the darkened surface to reveal a lighter shade below.