Showing posts with label project. Show all posts
Showing posts with label project. Show all posts

Tuesday, September 2, 2008

Intructables: Portobello Mushroom with Grilled Feta Burger

Instructables is a fascinating website where people create instruction to build stuff. I use stuff as a loose term because I have seen everything from computer tutorials to custom bikes to usb soda coolers and now to food. Many of the food instructables seem questionable, but this one looks appealing. I will be trying it tonight and reporting back.

http://www.instructables.com/id/Portobello_Mushroom_with_Grilled_Feta_Burger/

Tall Bike Update



Here is a picture, taken in the dark, of my tall bike with it's new paintjob. Yesterday I rode it over a mile. Next step will be to take it 5 miles and see if it hold up. The biggest problem now is that it only has 7 low gears. Something to work on. I need to have this thing dialed by next weekend for an 18 miel ride.








Friday, August 29, 2008

Tall Bike Build: Day 3

The least eventful and most productive session unfolded on the day 3. I set out with a mission to fully affix the second frame to the first, attach a steering tube, and maintain excellent geometry. All goals were reached.

The first step was to create a steering tube so that the frames could be properly aligned. To do so I welded two desk legs together. This created a longer than necessary tube that was almost exactly the same diameter as the original tube attached to the forks. Placing part of a smaller tube, taken from a broom, I was able to align the tube through the head tubes on both frames. As I slid the top frame down the steering tube I temporarily affixed it into place just as it came in contact with the lower frame. This connection roughly an intersection the pedal assembly on the top frame and the seat tube is on the lower frame. It is not a perfect match, as I suspected. There is just about half an inch of connection because the top frame sits slightly forward of the lower frame's seat tube. I tacked the frames in place and added a small bracket to the back of the petal assembly area on the top frame make the connection more rigid.

As an intermission, there was a knock at the door. Let me interject that I am currently wearing a grey leather jacket, gloves with the fingers cut off, dirty jeans, and white tennis shoes. Welding in flip flops and shorts wasn't working too well so I decided to gear up even though it was 80 degrees outside. So instead of answering the door I stuck my head out the window. There were two spindly guys with glasses and an awkward girl with a backpack. They wanted to know if my roommate lived here. My immediate response was, "Why?" They explained they were supposed to meet up with him to buy a linksys router. Long story short, I sold the geeky trio a router for 40 bucks and my roommate strolled in 45 minutes later. He had a friend with him and she did not seem to understand my tallbike endeavor. She wanted to know why I was making a tall bike. I just grinned and said, "because tallbikes are awesome." I don't think she will ever get it.

Getting back to work, I removed the temporary steering tube and started making the final steering tube. I cut down the temporary tube to the correct length. using a hack saw to rough cut it and a grinder to smooth out the ends to the proper length, the tube was ready for placement. At this point I reinstalled the front forks on the upper frame. The forks, and wheel for that matter, are still attached to the lower frame. I welded the tube into place and it all started to look like a tall bike. My welds are not real pretty but they are getting better. So, I did some grinding and welding until I was satisfied that the bike was sufficiently strong to hold my weight. And, just because I was itching to try it out, I tacked on some handlebars and put a seat on it.

I was so excited that I forgot it had two flat tires so I had to inflate the tires. Surprisingly they seemed to hold pressure. Next, I walked the bike through the house and out the front door so I could lean it against my truck. I hoped on top and pushed myself away. I was pretty nervous about the handlebar tack welds breaking, but they sufficed. It was dark, and the neighbors were looking wide eyed as I took a few coasts on the bike. It was an invigorating feeling. Tallbikes are awesome.

Wednesday, August 27, 2008

Tall Bike Build: Day 1

last night, I made the plunge. After a quick trip with Bubba to Harbor Freight I had a welder and and angle grinder. The thing to know about that place is that their prices are not exactly fixed. Always check their internet price. If you print it out they will always honor it; And, it is generally 20% lower. So following my own advice I checked online to find a welder that was $119. Then, having been dissapointed in the past, I called to find out if they had the model I wanted in stock. After a few minutes on hold, I learned that the last reamining model was out on the floor for display. To my good fortune, they were not going to sell me the floor model. Instead, I was offered the welder that was $199 in substitution. Free upgrade!

Now for a short lesson on welders. Welders are rated in several ways: amperage or current, voltage, and duty cycle. In my case, the original welder I was after had a duty cycle of 18% on low and 10% on high. Duty cycles translate into the amoutn of time you can use the welder in a 10 minute period (i.e. 10% = 1 minute of welding followed by 9 minutes of waiting). High duty cycles (up to 100%) are nice for personal use and essential for industrial application. In industry, if an employee who is welding has to stop and wait, then money is essentially being wasted . At home, it just gets frustrating to wait. Cutting to the chase, the welder I purchased in substitution has a duty cycle of 40% on low and 25% on high. Bottom line, I won.

So I hurried back to the dump--my backyard--and prepared to weld something. First order of business was the pesky cheese grater that needed a small spot weld. I blew a hole right trough it in about 3 seconds. Encore, was a knarly bead, surrounded by splatter and slag. Sweet. The grater is now customized and saved from a previously ineveitable trip to the dumpster. So far, total price to fix the cheese grater was roughly $150. That includes a welder, grinder, face shield, flux wire and electricity. If you need a cheese grater recycled do not hesitate to give me a call. I will make you a sweet deal. Just for my good friends I will fix their graters at a 75% discount. That is only $37.50 to restore your precious kitchen gadget. But, I digress.

Itching to bring a tall bike to life, I rapidly dismantled the extra mountain bike that I had in the back of my truck. This is a girls bike I found on the side of a road. The rear wheel is missing a spoke and the rear tube is 24" while the wheel is actually 26." Needless to say, this is a fine steed. Less than half an hour later--with the bike nearly dissasembled--I was implementing my hacksaw, which I pulled out of a dumpster, to cut the chain stay in order to remove the chain. This saw wasn't working well until I reversed the blade. Apparantly the yokel who threw this saw out didn't understand that the teeth are supposed to cut on the forward stroke. A long two minutes later, with a cramping the chain is off and still in one piece. Now to remove the last remaining problem. There were a number of cable guides on the bike. With an adjustable wrench I torque sideways on these buggers and they popped right off. Number of working bikes, aquired for free, now converted to a pile of parts: 2.

Being excited, and in a hurry, I flipped one bike frame over and stacked the other on top of it. Using a broomstick to line up the head tubes, I tacked the two frames together with some knarly welds. Then, I sat back a looked at it. I started to feel like it just wasn't lookign tall enough. I stared at is some more and it failed to impress me. It was 10:30pm and I had to get up at 6:00am the next morning, so I decided to give up for the night. Like most of my good ideas, the tallbike (1 word?) robbed me of sleep last night and took away ability to focus on other tasks today. Not really a problem. I enjoy it mostly. There is a certain look that creeps into my eyes. It warns you that I will stop at nothing to complete the task at hand.



So, I spend this morning daydreaming, reading, and calculating. 1 spreadsheet, 2 digital image drawings, and a few sheets of paper later I am ready to tear the two frames apart and try a different design. Using my calculations and bits of knowledge gleaned from a variety of websites, I can now explain why my origin plan yielded a bike that was shorter than my new option. The new version will be 15% taller using the same two frames. See the picture for the layman's explanation. Along the way, I learned the proper names for the various tubes that the frame is comprised of and how to measure their lengths and relative angles. Using excel, I created a spreadsheat that can project maximum safe saddle height--relative to the ground--and seat tube height based on chain stay run (horizontal length) and seat tube angle. In the end, it turns out that flipping the lower frame is not a good idea if you are trying to maximize the bike height. The downside is the seat seats further back from the center of gravity. Jsut a side note, I set the max height equation in a way to limit the furthest back saddle position to be directly above the rear hub. It seems like a bad idea to position my body behind the center of the wheel, although it would be interesting. Maybe, I could weld on a smaller wheel to be used as a wheelie bar...

Wothahellizat : Winnebago meets Mad Max

This vehicle was a steal at 175,000 AUD, but unfortunately it is no longer for sale. If only I had accepted all those credit card offers and used them to purchase this amazing machine $500 at a time...

"Wothahellizat was Australia's largest, weirdest and best-known off-road motorhome. We lived in it for six years and loved just about everything about it, but times have changed and so have our requirements for a motorhome."



http://www.robgray.com/index_files/index_wot.php