291–300 of 515 posts
By the way, push bikes (i.e. the hobby horse) are very common among toddler and preschool age children in my circles. I don't see why a wooden version of this couldn't have been common much earlier than 1817. Wood is sufficient for its construction, although I do suppose a metal bearing would be superior.
The unicycle was invented shortly afterwards. Here's a patent from 1869, for an over-complicated unicycle with a treadle mechanism instead of pedals on cranks. https://patents.google.com/patent/US87355 Many of the objections about how complicated the bicycle is don't apply to the unicycle. The Romans could have made a perfectly good one out of wood with brass cranks. But maybe it was even less obvious than the bicycl…
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I often wonder as I am building/fixing something (often my bicycle as it happens) and I happen to toss an extra screw in the trash how miraculous a simple screw of this type would have been to a middle-ages craftsman. The precision of keeping all those threads perfectly spaced is one thing, but the technology to make them in such volume at these sizes (often quite tiny), and in volumes so as to make them essentially…
There was a very interesting discussion on One Hour One Life mailing list about how fast we would go from prehistoric tech to modern tech if we knew all the steps and one key point was that we would have to make several iterations of increasingly precise machinery. I learned that in 1751, Vaucanson made this full-metal lathe: https://artsandculture.google.com/asset/metal-turning-lathe/... that was a kind of breakthro…
See the excellent book "Foundations of Mechanical Accuracy" by Wayne Moore of the Moore Tool Company for details.
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> Recumbent is horrible to ride in traffic (you are below the height of most traffic) Depends on the recumbent. Mine (an Azub Six) isn't - I commute through London on it every day. And cities are (slowly) getting better at keeping traffic out of the way. > and the handling is atrocious. How so? You have to take a different line through corners, but you turn later (front wheel is further back) so it's if anything easi…
> Depends on the recumbent. Mine (an Azub Six) isn't - I commute through London on it every day. And cities are (slowly) getting better at keeping traffic out of the way. I cycle through through and around traffic. I don't keep myself out of traffic I am part of it. I personally hate being in a cycle lane, because I know that many other cyclists normally aren't paying attention, don't know how to ride (they never che…
A rear suspension is stupid on any road better than cobblestone, but the shocked front fork on a hardtail is nice in many situations. If the commute is less than five miles or so, wider tires won't hurt anyone. I agree that I don't want knobby tires on the road, but it's easy to change tires. (All mountain bikes have easier-to-change tires than several road bikes I've serviced.)
I don't think the modern two wheeled in-line design is an obvious starting point or design iteration. It's not obviously user friendly either. Proof: 90% of the people reading this thread probably had to be "taught" how to ride a two wheeled bicycle.
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"The precision of keeping all those threads perfectly spaced is one thing " Making the first precision screw requires a "screw originating machine".[1][2] This is a special-purpose device which can make a better screw than the ones used in building it. Then you can install the first precision screw in a lathe and make more screws in harder metals. This is how precision is bootstrapped. [1] https://chestofbooks.com/ho…
> "The precision of keeping all those threads perfectly spaced is one thing" > Making the first precision screw requires a "screw originating machine".[1][2] This is a special-purpose device which can make a better screw than the ones used in building it. I hadn't realized screws would be needed to create a screw-making machine. I love that we have machines that make better versions of their own components, something…
Really when you get down to it, like computers, tools are used like 30+% of the time to build other better tools. Jigs, more accurate cutters, measurement devices, etc. With code that's things like test frameworks, rpc mechanisms, version control, code gen, etc. In fact in software engineering you're usually seen as a better engineer if you build things indirectly (frameworks) instead of mass production of the solution.
Check out the home machine shop series to see how you'd build up a tech stack from basically scrap metal and wood and Sand.
The Metal Lathe (Build Your Own Metal Working Shop From Scrap Series Book 2) https://www.amazon.com/dp/B007USU8HU/ref=cm_sw_r_cp_apa_i_Gh...
The lathe is pretty much the ur-machine, and a lathe is really just screws
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Yeah, whoever said that should try to make one without being able to go the the hardware store
Assembling a bike from parts would be a challenge for many people here. Assembling a wheel from parts is beyond most people, including many bike mechanics. In fact most wheels are assembled by machines, else labor costs would be too high. Used to be it was mostly serious amateurs and professionals that had them hand built. They’re more reliable, but I think it’s more to do with the combinatorial explosion of parts. M…
Just how shitty wheel would be admissible here? A wooden octagon?
>Yet it was a simple mechanical invention As a mechanical engineer, this statement baffled me. All manufactured technology exists in the context of the manufacturing capabilities available to the designer. The manufacturing tech had to be tremendously complicated before a decent bike could be made. Hollow steel tubes aren't simple. Ball bearings aren't simple. There is a reductionist viewpoint among "theory" people t…
The wheel existed before ball bearings - why are they necessary for bicycles? (is it an efficiency thing, for human powered?)
The safety-bicycle chain requires cheap precision mass engineering, but rope, rubber, axial rod (as in a car), or interlocking gears also work. Or direct, as in a penny-farthing. Or, no wheel power transfer, but push along with your feet, as in the Kirkpatrick bicycle.
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Right. And one point that cannot be stressed enough. Good steel, in quantity, only goes back to 1880. Lots of things that "could have been built in antiquity" foundered on that basic fact. Before Bessemer, steel was as exotic as titanium is now. The alternatives are not good. Cast iron? Too heavy and too brittle. Wrought iron? Maybe, but not that great. Lead? Too soft. Brass? Could work, but expensive. A king's kid m…
I often wonder as I am building/fixing something (often my bicycle as it happens) and I happen to toss an extra screw in the trash how miraculous a simple screw of this type would have been to a middle-ages craftsman. The precision of keeping all those threads perfectly spaced is one thing, but the technology to make them in such volume at these sizes (often quite tiny), and in volumes so as to make them essentially…
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Yes, but I don’t think that was the factor here. Ancient technology was astoundingly precise (see the famous Antikythera mechanism). I think the problem was roads. If you combine bad (or nonexistent) roads with airless hard tires, the result is much much less useful than any modern bike on any modern road. The first bikes were indeed wooden with wooden wheels. No ball bearings, no hollow steel tubes etc. But streets.…
The Antikythera Mechanism was a completely exotic Roman artifact. It was the space shuttle of its time. Not really a fair comparison. Dually, Romans were known for their extensive roads system. My family home sites directly below the Ancient Roman frontier in Germany, where you can climb a mountain and still find a 10 foot wide stone road they built 2000 years ago mostly intact