Wheelbarrow launched into air with powerful firecracker


#1

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#2

Old school fireworks were teh bomb.

I bought a box of bullets and shells from an auction once. At the bottom were these red and blue fire crackers called Polar Bears. They were the size of a regular black cat, but they were much more powerful. No wonder kids lost fingers back in the day.

I put a black cat under a tuna can and it went maybe 6 feet high.

The Polar Bears launched them over the high power lines in the back yard.


#3

Wow.

A nice exercise could be opening it, weighing the flash powder, and analyzing its composition…
[tempt][prod][tempt]


#4

Yes!
(It is a minor miracle that I did not lose any fingers in my 7-25 year old period…)


#5

If it’s black powder it is going to be quite easy to analyse but not so easy with only readily available resources. Dissolving out the nitrate is easy but testing for an alkali nitrate is tedious - the easiest way to start is to boil dry and melt a sample.
To test for sulfur you really need carbon disulfide (kids, do not try this at home) to dissolve out and crystallise.
And carbon…it needs to be distinguished from maganese dioxide which you can do by reacting with a suitable acid. I forget the reagent for manganese, it’s in the book in the attic I haven’t looked at in over 30 years.
But if there’s anything else in there, like aluminum powder or a percholorate, it starts to get complicated.


#6

Well - first you need a time machine to go back to the early 90s or late 80s and stop me from using them all.


#7

What about using microscopy? The grains are discrete pieces of individual pure materials.

I am not sure how well it would actually work, but what about USB microscope, thin enough layer so several grains of each material show up without contacting each other, and heat the sample and watch what happens at what temperature?

Most of the materials have well-defined melting or decomposition temperatures, and most of the rest can be inferred from the other ones present.

Also, a variant could use immobilizing the grains in suitable adhesive, and subjecting them to various reagents.

Then there’s Raman microscopy but then we’re getting into a rather esoteric area…


#8

Our high school chemistry teacher told us about the student that stole a giant chunk of Sodium metal which they then placed under an upside down garbage can that was packed with snow. I guess that it blew quite high. In his mind, he was warning us against the dangers of the Na metal, but what he did was put some ideas into the minds of half of the class… (unfortunately, he now kept the jar full of Na in a more secure location)


#9

Have a look at…

…and scroll almost down to the bottom for “Propulsion of steel plate cap”. It is a small (0.3 KT) nuke and a 0.9 ton piece of armour plating that either evaporated or reached many time escape velocity. Maybe not as impressive as landing the right way up, but perhaps the first man-made object to leave Earth’s gravity.


Huffing Boing Boing
#10

Didn’t achieve escape velocity yet? Keep trying, bro. You just need more bombs!


#11

I remember when my old pal Lefty got ahold of some of those once…


#12

Would centrifugation of a saturated solution be a start? I’ve been getting perchlorate from matches recently and the glass powder falls to the bottom really fast. If there are oxide powders I don’t see why this wouldn’t work.


#13

My favourite thing about this is how neatly the wheelbarrow lands.


#14

Probably would. But the question is if you want to isolate perchlorate (which may have a better alternative in making it by electrolysis (todo: make a sample explosive from sugar and salt - ban this, Mr. Bureaucrat!)), or do the composition analysis.

What do you use as the centrifuge?

Edit: I just was discussing high-G testing of electronic parts. A rough calculation shown that this motor can run at 35000 rpm with ease


and needs one of these controllers:

According to an equation from here:
http://clinfield.com/2012/07/how-to-convert-centrifuge-rpm-to-rcf-or-g-force/
you can achieve 30,000 g on a 20mm radius rotor at that rpm.

Formidable…


#15

It’s aerodynamic in the self-stabilizing way. The wheelbarrow tub looks roughly kind of like space reentry vehicles.


#16

I might try electrolysis later. Potassium perchlorate has really low solubility (part of me isn’t sure how much of the powder is ground glass) and the matchheads seem to disintegrate easily in water. So far it’s a giant pain. The filter paper clogs quickly and I don’t want to use celite because I’m worried it will cool the solution too much. It’s become mostly a “can I do it” experiment at this point. I still have my standby of stump remover and sugar to fall back on by the time the fourth rolls around.

I don’t have a centrifuge, or a motor that will serve me. I have had very limited success swinging stuff around. Unfortunately, I have approximately zero dollars all the time, so everything I do is usually based on materials I have on hand. I might try using my bicycle wheel, now that I think of it. But my centrifugation needs are limited.


#17

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