
How to Almost Build an Engine With Only Parts From the Hardware Store [video] - DanBC
http://howtolou.com/engine
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SwellJoe
It's kind of fascinating, to me, that internal combustion engines won the car
war for so long. Electric motors are _so much simpler_ to build, and _so much
more efficient_ from an energy usage perspective. I understand why electric
lost out (energy storage, range of vehicle), but I think it could have gone a
different way had there been just a couple of nudges in the electric direction
at the right time. And, what a different world we'd live in, if those nudges
had happened...

~~~
DanBC
It's interesting that I can make a toy electric motor by with a battery, a
magnet, and some wire.

While some people do make tiny internal combustion engines the work involved
in incredible.

([http://www.youtube.com/watch?v=mLn7xG8vuPQ](http://www.youtube.com/watch?v=mLn7xG8vuPQ))

World's smallest V12 engine:
([http://www.youtube.com/watch?v=m3KdpzL3Hkk](http://www.youtube.com/watch?v=m3KdpzL3Hkk))

Making model IC Engine valves:
([http://www.youtube.com/watch?v=Nofj1CGSCM4](http://www.youtube.com/watch?v=Nofj1CGSCM4))

~~~
WalterBright
You don't even need a magnet. I made an electric motor as a kid out of nails,
wire and a battery. It worked pretty good.

But, being a boy, I wanted it to work better. So I replaced the battery with a
lamp cord and plugged it in. It promptly burst into flames. Awesome!

~~~
speeder
Once I plugged a toy race track to the outlet (in portuguese we call it
"Autorama" I dunno the name in english), I knew enough of physics to expect it
to burst in flame...

But instead the car got REALLY, REALLY, REALLY fast, shoot out of the track
and smashed into the wall.

Of course, I happily put a second car on it, and changed the track so that the
car does not end smashed, and indeed, I could launch cars all over the place.
Also as the car raced, sparks came out of the contacts with the track.

Now that I am older and know even more physics, I have no fucking idea on how
I made a DC motor work only forward with a AC current.

~~~
JoshTriplett
Assuming the track was designed so the cars go forward no matter which
direction you place them, the cars likely had a small diode-based circuit to
always feed the current into the motor with the same polarity. When you fed an
AC current into the track, that circuit in the cars would have acted like a
rectifier, turning the AC into poor-quality, high-voltage DC.

The sparks would come from feeding way too much voltage in, enough to jump the
gaps caused by momentary losses of contact between the track and a fast-moving
car.

~~~
speeder
Diodes! Great idea, I should have thought of that.

~~~
mangamadaiyan
I'm guessing your mains supply would've been 230v/5A - in which case I have to
say I'm surprised that it didn't blow the diodes out :) I remember plugging a
1N2001 (or similar) into a wall socket, and turning the switch on to watch the
diode blow out as a schoolboy.

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larrys
Well first he has certainly not taken safety into mind when doing this
project.

Look at the way he's dressed. (With no protection clothing or eyes or
anything).

Look at how close he comes to the gasoline.

Look at how he's seated so he can't even get away quickly.

Look how there is no protective shield.

He doesn't even appear to have anyone else there in case of an emergency.

He has enough intelligence and curiosity to attempt this but not enough to
protect himself. More or less what I would imagine from someone much younger,
certainly not a grown man.

~~~
noselasd
I just watched it, what in particular seemed so dangerous it would warrant so
much precaution ?

~~~
larrys
Aerosol can. Spark. Gasoline.

~~~
jessaustin
Meh. You folks should have misspent more of your youth burning shit down.
Gasoline is highly flammable, but it doesn't light without a spark. Also, the
small amount of gasoline he's got in his carb will only produce so much flame.
I'm glad he appears to be running this outside. I probably would have worn
safety glasses, but then I only have one eye.

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ricardobeat
[http://www.youtube.com/watch?v=8TCe9NKtP90](http://www.youtube.com/watch?v=8TCe9NKtP90)

~~~
jessaustin
Awesome! I only watched the first two episodes. The kid at the beginning is
doing it right. The old man with the giant brushpile should be using diesel
fuel, with perhaps a couple of old tires and a very tiny amount of gasoline
since diesel fuel can be difficult to light. (But it burns much steadier,
rather than exploding all at once.)

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msisk6
I don't know -- while I admire what he's trying to do here, it's just a little
too cargo cultish.

There's a lot of engineering in internal combustions engines and all that info
is readily available. Things like compression ratios, spark timing, and fuel-
air mixture ratios; all very important but it seems he didn't give any thought
at all to this before jumping in.

A little thinking ahead of time could have saved him a lot of time and money I
think.

I'd suggest the author spend a bit of time looking at the designs of the
Wright Flyer engine and that in the original Model T and going from there.
These two engines are of very simple design and worked reasonably well. And
there's a ton of technical information out there on these, too.

Oh, and some fabrication skills with a lathe and mill could be handy, too. I'm
always amazed at the length some folks will go to with building stuff from
hardware store stock. A community college class in machining and a cheap lathe
and mill opens up a whole new world for any maker.

~~~
numbsafari
I agree that he should have done more research before jumping in. A quick
Google search for animations of simple two-stroke engines would probably help
him get that working in fairly short order.

I disagree, though, about needing to go crazy with the craftsmanship. I mean,
if the purpose of this is to build something experimental, or something that
could be used to illustrate to kids how an engine works, having it NOT be
craftsman-like might help demystify the whole thing.

I really like that he has built it onto a piece of plywood. It reminds me of
those old electronics builder kits you could buy at radioshack. Would you want
to actually use one of those as a real radio? No. But building a simple radio
that actually functions where you can see all the pieces really helps to make
it real.

So, from an educational perspective, I think the simplicity of it is helpful.

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jacobparker
I love it! Keep up the good work (if the author sees this thread)

