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How to Almost Build an Engine With Only Parts From the Hardware Store [video]

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Re: How to Almost Build an Engine With Only Parts From the Hardware Store [video]

#31

Post by bigiain »

archgoon wrote: post #10
sandfox wrote: post #4

Earlier quoted context omitted.

And this is why he has done this and you haven't :-p Though seriously, when was HN ever about health and safety?

> Though seriously, when was HN ever about health and safety? The computer version of safety is called security. And HN cares a lot about computer security.

Yeah sure – when it's appropriate. I've got a RaspberryPi within armsreach that's still got the stock ARCH-ARM image with it's default login of root:root.

Yeah, I wouldn't deploy it on a public internet exposed network, or give it to someone else who wasn't aware of the implications or consequences of such an insecure machine – but in the privacy of my home network it's just fine.

I assume this guy is the same – he needs some increased safety if he wants to show this thing off in public, but in hs own shed he's got every right to accept risks for himself that are inappropriate for other people.

I've seen equally and much more "dangerous" projects at Burningman – hell, if he gets this running with any sort of reliability, attaching it to a bicycle and riding it around at Burningman would be a _fabulous_ idea!

Re: How to Almost Build an Engine With Only Parts From the Hardware Store [video]

#32

Post by bigiain »

larrys wrote: post #2

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 t…

FWIW, I regularly expose myself to pretty much exactly the same danger he's choosing to expose himself to - just because the engines I work on in my garage are made by Ducati or Mazda, it doesn't make my sitting down in non-protective clothing with open containers of gasoline and no eye protection noticeably "safer". (In fact my jeans still smell slightly of the gasoline I spilled on them on Saturday…)

I think you'll find a vast number of "grown men" who'd recognise the risks you identify here, and say "Yeah, it's not as safe as sitting on the couch watching TV. Grab a beer and stand back in case this explodes…"

And while you might question their intelligence – they'll just as incorrectly question your manhood for doing so…

Re: How to Almost Build an Engine With Only Parts From the Hardware Store [video]

#33

Post by bigiain »

jevinskie wrote: post #14
larrys wrote: post #11

Earlier quoted context omitted.

Aerosol can. Spark. Gasoline.

Yup, the gasoline splashes out of the bubble carb on every stroke!

You've never run a motor with the airfilter off, right?

My motorcycle motor produces a beautiful cloud of gasoline droplets standing maybe 4 or 5 inches tall above the carburetor throats when you crack the throttle open.

There's thousands of car/bike enthusiasts who see that in their garages every weekend. They're not dying in catastrophic accidents all the time.

Re: How to Almost Build an Engine With Only Parts From the Hardware Store [video]

#34

Post by 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.

Re: How to Almost Build an Engine With Only Parts From the Hardware Store [video]

#35

Post by TheLegace »

bigiain wrote: post #30
mikeash wrote: post #29

Earlier quoted context omitted.

That's not a fair comparison at all. Building a hobby V12 like that is like building a modern brushless high-efficiency electric motor, not like building the toy you mention. The combustion engine equivalent to the toy electric motor would be a simple stirling engine or even a Hero engine. These can be very easy to build.

Building a high-efficiency brushless motor isn't particularly hard - especially if you're happy to consider "reusing/repurposing components from readily available 'junk'", or buying kits like this: http://www.customcdr.com/cgi-bin/ccp51/cp-app.cgi?usr=51H817... (I've built both kit versions and "from scratch" motors built with parts ratted from cd rom drive motors with a few bucks worth of rare-earth magnets.) Buildi…

There is an open source project called Open-BLDC, I really like the project and use it to help me make a regular Brushed DC motor controller, eventually I'll want to play with BLDCs and there is some fine work done by the author of the boards and code esden.

http://esden.net/2010/09/19/open-bldc-v0-3-hardware-based-cl...

Re: How to Almost Build an Engine With Only Parts From the Hardware Store [video]

#36

Post by [deleted] »

larrys wrote: post #12
KamiCrit wrote: post #9

Earlier quoted context omitted.

Like a true armchair warrior, how many engines have your tried building?

I've purchased and I've operated expensive machinery and I've seen what happens when people don't take appropriate safety precautions. He could have built an enclosure and put this on a table similar to what is used in lab experiments. But please tell me what this has to do with whether I have personally tried to build, in particular, engines?

[deleted]

Re: How to Almost Build an Engine With Only Parts From the Hardware Store [video]

#37

Post by [deleted] »

vacri wrote: post #27
jasonwatkinspdx wrote: post #16

Earlier quoted context omitted.

Yeah. It's worth noting that for engines in stationary devices like fabrication tools and machinery, electric totally won. So what made the difference with cars wasn't just the engines themselves, but rather the energy storage/distribution network. Now that we have batteries that are good enough at a cheap enough price, electric is gaining fast despite a lot of cultural opposition.

I'm not sure about totally won - here is a demonstration of a gasoline-powered flashlight, which might create a resurgence of this method for power tools. At 0:30 he expounds on the advantages of the device. https://www.youtube.com/watch?v=OcdVaslktBE

[deleted]

Re: How to Almost Build an Engine With Only Parts From the Hardware Store [video]

#38

Post by jasonwatkinspdx »

walshemj wrote: post #22
jasonwatkinspdx wrote: post #16

Earlier quoted context omitted.

Yeah. It's worth noting that for engines in stationary devices like fabrication tools and machinery, electric totally won. So what made the difference with cars wasn't just the engines themselves, but rather the energy storage/distribution network. Now that we have batteries that are good enough at a cheap enough price, electric is gaining fast despite a lot of cultural opposition.

It took hundreds of years to go from belt drive in factories to individual electric motors which probably didn't get installed in large numbers until post WW1 Even in the late 70's the mechanical technician courses in the UK required you to be able to design an old school belt drive.

Yup. I am quite familiar. My great grandfather made a minor fortune in the 20's with a service company that would refinish the bearings used in shops with overhead drive shafts, etc.

Re: How to Almost Build an Engine With Only Parts From the Hardware Store [video]

#39

Post by ams6110 »

SwellJoe wrote: post #5

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 diff…

Electric cars needed far more than a "nudge" and still do. Even with today's state-of-the-art battery technology the range, recharge time, and cost equation still doesn't work for most people. With the lead-acid technology of the day, it was never even close compared to internal combustion.

Re: How to Almost Build an Engine With Only Parts From the Hardware Store [video]

#40

Post by deepblueq »

noselasd wrote: post #8
larrys wrote: post #2

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 t…

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

No rev limiter (at least not that I saw), at least one potentially peaky (high-RPM biased) timing parameter (intake valve), lots of parts that aren't built to take high RPM, and a lightweight flywheel. If it were to suddenly start working properly, it could go flying apart with lots of force in very short order.

To be fair, it would take lucky (or unlucky, depending on how you look at it) ignition timings, since with that system they're all over the place.

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