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 Wooden bicycle
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Steven Challenge
recumbent enthusiast

Netherlands
142 Posts

Posted - 04/23/2012 :  07:58:38  Show Profile  Reply with Quote
I've read on several threads here that many are looking for alternative materials. Hightech lightweight materials cost a fortune and are often not enviromentally friendly.
Before I bought my recumbent, I had a DIY wooden bicycle.
It's made from several layers of plywood, glued together with construction glue. No bolts, no sub-structure. Just about 10cm inside the wood at the moving parts. It used to be a hardtail mountainbike, so it had 3x7 gears. Although it looks heavy, it wasn't more heavy as a regular stretched cruiser.





It looks difficult to make, but it was actually easy to do. I didn't have to do a lot of allignment, because I had the perfect straight shape of the plywood as a guideline. I think, with some calculations before manufacturing, you can reduce the weight significantly.
(total cost of the bike: used bike I already had, about 70 of plywood, glue and laquer 50, miscelanious 20 = 140)

For questions, feel free to ask.

Larry Lem
human power expert

South Sandwich Islands
2304 Posts

Posted - 04/23/2012 :  11:17:58  Show Profile  Reply with Quote
How is the headtube bonded to the plywood?

Larry Lem
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Steven Challenge
recumbent enthusiast

Netherlands
142 Posts

Posted - 04/23/2012 :  12:03:15  Show Profile  Reply with Quote
I can't seem to find the "making of" pictures from this bike. I made another smaller version for my next door neighbour kid.

this was the design.


this was the plywood with the part cut out where the headtube was going to go.


This is a test assambly picture, right before painting.

So to answer your question, Larry, the headtube is glued into place. Tightly clamped bitween the cutout of the center plywood parts, and the outer layers. Trick is to make the center plywood parts the same thickness as the headtube.
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Larry Lem
human power expert

South Sandwich Islands
2304 Posts

Posted - 04/23/2012 :  14:03:47  Show Profile  Reply with Quote
On the big bike, the wood barely covers half the diameter of the head tube.

Assuming the head tube is steel, are there stubs of a top tube and down tube welded to the head tube that penetrate into what appear to be recesses in the wooden frame? If so, these tubes aren't shown. I cannot imagine the head tube staying attached to the wood frame under any load if it does not have such.

Larry Lem
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Steven Challenge
recumbent enthusiast

Netherlands
142 Posts

Posted - 04/24/2012 :  00:03:58  Show Profile  Reply with Quote
The head tube is aluminium. The donor bike was a Y-frame. I left about 18cm of the 10cm wide down tube on the head tube. So a surface of 18x10cm is hidden in the plywood frame. I let the head tube half visable for the illusion of an impossible construction. Apparently, it worked. ;)
I made sure the wood fitted perfectly around the aluminium. The PE construction glue is strong enough to hold the plywood together. In fact, if the structure would break, it would break at the wood, not the glued parts. When riding, the frame only squeeks a little when I really push the pedals.
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