PDA

View Full Version : How practical is this guys idea? He's pushing the bicycle envelope.



Your Old Dog
10-16-2012, 06:53 PM
http://www.engadget.com/2012/10/16/cardboard-bicycle/

Maybe we'll be machining cardboard in the future.

Spin Doctor
10-16-2012, 07:07 PM
One of the interests I have is building Cardmodels. Including some of my own design. Even if I don't finish the project I try to see how far I can push the material. For one project I built a cell structure 5 inches square and one inch thick. Top, bottom and cell plates were .040 chip board (that is what the stuff on the back of pards of writing paper or cereal boxes is called) faced with 65lb card stock both sides. The cells were on one inch centers. When I put it in a spring compression it maxed the gage out at 500 lbs. In order to bring it to the failure point I had to put it in a ratchet type arbor press. Plus remeber that Rutan's Voyager (?) that flew around the world is couragated card board at its core. I just don't believe the 20 bucks part

Carld
10-16-2012, 07:10 PM
Probably a good temporary bike.

SteveF
10-16-2012, 07:45 PM
" In fact, this bicycle doesn't use any metal parts at all "

Hate to be so picky but that timing belt sure looks like it is going around an aluminum gear to me. Without metal parts I'd love to see how the shifting mechanism works unless this is supposed to be a one speed bike, in which case good luck getting many people to buy it.

Steve

Spin Doctor
10-16-2012, 08:39 PM
Plus most likely steel cable in the brakes. And what about bearings. Sure they could be sleeve type but the friction is going to go up

alsinaj
10-16-2012, 09:48 PM
Spin Doctor,

I'm interested in paper honeycomb structures. How are they made, and how can they be waterproofed? If you can point me to some information, I'd appreciate it.

JA

oxford
10-16-2012, 10:14 PM
I don't see how that can be made and sold at a profit for $20. I don't even think it can be made for $20.

mickeyf
10-16-2012, 10:27 PM
good luck getting many people to buy it

This is a third world bike. There may well be more single speed bikes in use in the world than the fancy dérailleur types we typically use in developed countries. I seem to remember Jules Verne had an airship made of paper in one of his writings, over a hundred years ago... More power to him.

In any case "The market will decide."

A.K. Boomer
10-16-2012, 11:14 PM
Give me just one city block and I could turn that thing into pulp...

hope his wifey reminds him to bring it in in the rain...

The real question is "WHY"

darryl
10-16-2012, 11:20 PM
Car timing belt? Where can I get one of those for less than $20?

kendall
10-16-2012, 11:25 PM
I don't see how that can be made and sold at a profit for $20. I don't even think it can be made for $20.

They'd be relying on the government tax credits etc for 'going green'

Start company, get the grants, build a ton of bikes, declare bankruptcy and sell them for $20 at the auction.

Peter S
10-17-2012, 02:08 AM
unless this is supposed to be a one speed bike, in which case good luck getting many people to buy it.

Strangely enough....single speed bikes are becoming trendy again, very simple and light, no freewheel, so you can brake with your legs, they have competitons for them too.

I like this guys work. I have used so much cardboard and duct tape over the years I have a soft spot for this material.

vpt
10-17-2012, 07:54 AM
What a waste of cardboard. :)

I bet it would heat my shop for at least 20 minutes!

bobw53
10-17-2012, 08:07 AM
His maintenance-free bike uses a "secret" mix of organic materials to make it waterproof and fireproof, and is then lacquered to give it a friendlier appearance.

Some type of resin I'm guessing, so he's basically making a fibre glass type of a thing. Cardboard reinforced "organic" plastic.

I'm curious of the ratio of cardboard to "secret" mix.

Your Old Dog
10-17-2012, 08:45 AM
Strangely enough....single speed bikes are becoming trendy again, very simple and light, no freewheel, so you can brake with your legs, they have competitons for them too.

I like this guys work. I have used so much cardboard and duct tape over the years I have a soft spot for this material.

I agree. I like to see how other peoples minds work. Who ever thought we be seeing aircraft wings out of carbon fibre.....and what the hell is carbon fibre anyway? !! If he needs to use non-cardboard bearings and drive belts he has still demonstrated that cardboard is much stronger then we normally think of it as being.

michigan doug
10-17-2012, 01:52 PM
Cardboard IS a sort of carbon fiber composite material. With the right resin, waterproof is no big deal.

The no metal thing is not quite true. Maybe he means no metal in the frame...

I'd be impressed if he can bring it to market for $50.

I'll wait to see them on the shelves.

Hope he makes it.

doug

Spin Doctor
10-17-2012, 07:44 PM
Spin Doctor,

I'm interested in paper honeycomb structures. How are they made, and how can they be waterproofed? If you can point me to some information, I'd appreciate it.

JA

Basically a card version of a hollow core door really. Suprisingly strong in a verical load. Look at some of the honeycombed packaging that you see with appliances and such. As to waterproofing. I suspect some sort of resin would be needed. Plus in the 1800s there were companies making French Empire style furniture out of paper mache. I wonder how much is still around. Also one of the first, if not the first stereo lith process used layers of paper glued up and cut with a laser. The finished parts could even be worked with wood working tools IIRC

Bill736
10-17-2012, 08:34 PM
Back in the 1960s in my dad's boat building shop, we made our own honeycomb core structures with smooth fiberglass faces, and built fish boxes for charter boats with it. The paper honeycomb was impregnated with polyester ( fiberglass type) resin, the same resin used to make the smooth faces. We also used the honeycomb material for boat seats, bulkheads, and other assorted projects. It was lightweight, but quite rigid, and a 1 inch thick piece could support a 175 lb. man when set between two blocks 2 feet apart. It wasn't high tech by today's standards, but such structures still amaze me. Similar structures can readily be found in nature, such as with the dried stems of Polk weeds , which have a rigid outer cover, and a lightweight inner support structure.

Bill736
10-17-2012, 08:43 PM
I don't mind a single speed bike, but one with no free wheeling ability is a pain to ride. I can remember my first bike as a child had no free wheeling , and if your feet come off of the pedals, they beat your ankles to death. I was very happy indeed to move up to a bike with a coaster brake.

john hobdeclipe
10-18-2012, 11:56 AM
http://www.woodworkingnetwork.com/news/woodworking-industry-news/Thonet-Commissioned-Wood-Bike-Priced-at-70000-173329481.html

kendall
10-18-2012, 03:24 PM
http://www.woodworkingnetwork.com/news/woodworking-industry-news/Thonet-Commissioned-Wood-Bike-Priced-at-70000-173329481.html


Another bike that is interesting:
http://www.bikebamboo.com/
Actually a fairly practical material.