Yesterday afternoon, I turned my 21 year old Chevy (Isuzu) 6.6 Liter Duramax Diesel into a plug-in hybrid.
Behold:
Okay, not really.
I just became annoyed with the process of plugging in the block-heater during the sub-zero temperatures: kneel down in front of it, use both hands to carefully pull of the dust cap, plug in the extension cord. Then when I want to leave, use both hands to unplug the extension cord, then both hands again to put the dust cap back on the pigtail.
Too much effort.
The fix was to add a weather-resistant bulkhead power inlet. I can now — more easily, and single-handedly — just plug in the extension cord.
Future addition is to add a Battery Tender so it keeps the batteries in a peak state of charge.
Driver Needed. CDL +Hazmat required. Must know how to apply brakes to avoid a bus…
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I’m looking around trying to find something to back the current thinking about pure acetylene’s propensity to spontaneously explode over 30 psig. Clearly, we have some limits on use/storage/movement/and so forth, but the curious part of me really wants to know “how did we learn that?”. I mean, a scientific paper describing how exactly that was determined would be great. But I stumbled across the above.
It’s not the result of a high-pressure explosion of acetylene, but instead of one high pressure cylinder that outgassed (secondary to the collision), then combusted either against a vehicle’s hot exhaust or was ignited by a rich-burning engine.
Then all hell breaks loose.
You’d want an acetylene cylinder to outgas when it’s being boiled. Much more preferable. Outgassing with a dangerous but impressive flaming spire is significantly more agreeable (they have plugs that will melt to release the gas) than having the 250 psi steel bottle burst and release its high-pressure acetylene+acetone mix into a flames.
Rapid decomposition ensues.
Fine… explodiness ensues.
Those bottles weigh perhaps 60 kg. Empty, they’re perhaps 55 kg. If you knock the valve off of it, it’s a rocket.
Those rockets are not at all predictable in their paths. While you -do- see those impressive flame plumes behind them, it’s not the fire accelerating them. Any acceleration is entirely from the gas pressure inside the cylinder.
Scary stuff.
So what about oxygen bottles? Typically oxygen bottles are at slightly higher pressure than acetylene. About 2000 psi compared to acetylene cylinder’s 250 psig. Industrial, medical, aviation — with a few uncommon exceptions (low-pressure O2 tanks for example), oxygen bottles are typically charged to about 2000 psig.
It’s a bit scary to see what even a small medical-grade O2 cylinder can do when its valve is expeditiously detached from a 2000 psi tank… inside of an old-style ambulance. That little rocket very quickly added an extra window to truck’s metal box.
Fortunately, while oxygen isn’t flammable, it does tend to aide in combustion. Think Fire Triangle. Fire would have been horrifying.
Speaking of oxygen and fires, many years after I observed the result of what an unsecured O2 cylinder could do to an ambulance, there was a guy who once used LOX to rapidly (instantly?) create a ready to use BBQ grill by using a single match. Ah… here’s it is:
Spotted on the Tubes of You — a hand-prop start of a rotary engine.
Now, for everyone else, this could be labeled “How Not To…”. No, nobody was puréed by the spinning prop. But there were so many possibilities for things to go pear-shaped rather quickly.
Inside of a hangar
Against a wall
The position of controls and the motor (and prop!) limit your vectors for egress
Walking around a spinning prop
Without ear protection (or eye protection)
And horrifying hand-propping technique involving walking slowly backward
Steve Thorn (FlightChops) and Kris Finkbeiner (with TacAero) demonstrates what we like to call the right way to hand-prop.
I rather like the effort Steve has shared in aviation through FlightChops. Rather inspiring, honestly.
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A few last moment remarks on walking (staggering?) backward — and this applies to walking, running, bicycling, motorcycles, cars, trucks… but probably not locomotives (unless you’re its engineer):
Always watch where you’re going.
Never watch where you were.
Remain focused on the now and never fixate on what was.
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Also, also: Just remembered that Steve did a couple of episodes on hand-propping. Here’s one that he covered on a de Havilland DHC-2 Beaver:
We are deeply saddened by what’s transpired in Sri Lanka. Our thoughts go out to everyone across Sri Lanka and to our friends and families around the globe.
the rest of me 