JamJars

[Mike Everman]

Hmmm, let's see....
Yep. Not mine, though. Steve made this fabulous video:
http://www.pulse-jets.com/phpbb2/files/jam_jar_0001.wmv
Such a good one. I'm going to watch it a oouple more times.

[Eric]

If I remember tomorrow I'll try to make one up and get it on video at 60 FPS :)

Eric

[Mark]

I kind of liked this jar too, but I didn't follow up on it. It was a real self-starter. A platinum sponge ignited the jar shortly after you added the methanol. Spontaneous combustion meets pulsating combustion.
Mark

[Mark]

I should say on my last post that when I said I didn't follow up on it, I meant that the fragile platinum wire surrounding the platinum sponge took a beating and the wire was torn from the sponge. The wire is finer than hair, more like spider silk and as such didn't last. The platinum sponge pellet heats up spontaneously, whereupon the attached platinum wire heats up and it is this glowing wire that ignites the methanol vapor, a stairstep way to ignition. Another way I have gotten ignition is to sprinkle a tiny bit of platinum coated alumina powder into a flask. The little particles float down and glow and this glowing dust will bring about ignition too. I bought a 4 ounce jar of platinum on alumina for not too much, as to surface coat aluminum oxide is to not use much platinum, kind of like gold leafing I suppose.
I bought some platinum wire but just haven't gotten around to designing a more robust lighter mechanism or figured a way to keep it out of the turbulence.
All it was really was the guts of a platinum lighter that hung on the inside lip of the jar. Still, it is interesting how tiny a "magic fire starter" can be, no bigger than a BB with some wire, I used gold plated nickel wire, but any wire would do to hang it, on the lip of the jar.
Mark
PS It is all about surface area, for even finely divided iron will make a shower of sparks by merely sprinkling it from a sealed test tube, but with platinum the platinum doesn't get used up like iron does by turning to iron oxide, burning itself up in air like a meteorite. Interestingly, some hand warmers use iron which reacts with the air and yet other hand warmers use a platinum coated woven wick of asbestos which reacts with a fuel that you can refill your lighter with. I have sprayed such a wick with methanol from a spray bottle and this too will ignite the misted alcohol cloud.

[Mark]

I was just toying with a collapsible cup I bought on eBay a year or so ago and finally got around to attempting something with it. I found some cap-like piece of metal in the kitchen sink repair part of a hardware store and just taped it onto my cup as you can see. If I hunted around, I could probably have found a flat washer that would have also worked for a cap and thus made the signature of the collapsible jam jar smaller.
These cups are made to carry in your pocket. I have also pondered a collapsible pulsejet that telescopes to length.
Anyway the little guy did me proud. I let it run for about 10 seconds and then stopped it and spritzed it with water as a quick afterthought having a water bottle nearby. The tape held up fine oddly enough, but of course the jar was too hot to lift or carry before the cold shower I gave it. I then tried to collapse it by rapping it on the top but since the metal expanded, only one section collapsed for some reason.
It sure purrs fast and steadily without hesitation. One other ridiculous idea I had was to put the platinum wire spontaneous combustion device inside it. Then if if it had a way to break apart a little capsule of methanol inside whilst extending it to length, very soon after you extended it, the expanding cup/jar might spring to life and amaze your friends.
Just being nuts.
Mark

[Mark]

Here's some stainless steel cups, a bit different design with more segments than mine, which I like because it collapses smaller, but a "funny" base instead of a flush base like mine. Interesting how they are built really, how they would fall apart without the base segment.
Again, it amazes me the blue electrical tape held up to a ten second run, I just stretched it as I wound it around, just slightly less than two windings. I recommend having some electrical tape around for experimenting, it's very useful.
Mark
http://tinyurl.com/y6fbcn
http://tinyurl.com/y7kl5e
http://tinyurl.com/y84vss

[Eric]

You should try telescoping it while its running :D

[Mark]

I was thinking the jar might collapse in the verticle by itself when I lit it, sort of how a too thin Lockwood waffles at the tailpipe, gets imploded. But it didn't. I just think it would be neat to make a long slinky pulsejet out of many collapsing/interlocking segments. You could lay it on a table like a snake and then pull it tight and fire it up, or collapse it into small flashlight length. Or hold by one end and swing your arm as if to cast a rod and it would snap into shape.
... which reminds me of that weapon they sell that extends in the same manner. Then you can whack people with it. Another kind you cock it by forcing the lengths into each other and by pressing a release button, it fires a punch equivalent to a boxer's fist in force. Maybe you could borrow parts from that as a prototype. Or anyone have a pirate's telescope. ha
Mark
http://tinyurl.com/y85vad

[larry cottrill]

I see that at that link:

http://tinyurl.com/y85vad

they offer original Mark V air hats, just like I've always wanted, for 400 bucks US !!! Just click on the diving helmet picture. Turn one of these upside down for a big jam jar experience - ha! You could observe the flame formation through the safety grilled front window ...

L Cottrill

[thecheat]

I like the expandable cup!

Oh, and perhaps you could reverse the idea, rather than having a capsule of methanol, have a capsule of platinum wire! just glue one end to the bottom, and the other, attach a string to the top and the top of the cup. When you pull, pop! the platinum is revealed to the methanol and the reaction gets underway.

[Mark]

With the all silver lighter pictured you have to put the cage inside the fat section that contains a hollow cotton wick impregnated with methanol. But with the gold and black lighter, as soon as you take the lid off, the platinum sponge and wires are dangling/mounted in the center of a hollow cotton wick. Sometimes for fun I would just take the lid off and quickly cap the gold and black design and it would fire with the cap trying to pop off with a jet of hot gas out that tiny hole in the silver side, there for air convection I guess.
Anyway that black, silver, and gold colored lighter lights when you expose the platinum sponge and wire to air. And even the other lighter does that too in a way although it is less direct.
The black and gold lighter came with an extra cartridge and I just took the platinum bead/sponge and wire out of it and dangled/mounted it in a jam jar to effect the spontaneous combustion/pulsating combustion marriage. It was funny to add methanol to a jam jar and wait a few seconds for the "magical" starting/firing. It's just odd to hear a jam jar run/cycle up from such a strange starting method. It's startling somehow.
Mark

[Mark]

These lighters will also cause hydrogen and oxygen to detonate from the presence of platinum sponge, (high surface area), and a simple stream of hydrogen gas will light just as easily as methanol with these lighters.
Here's the man who thought of it.
Mark
http://en.wikipedia.org/wiki/D%C3%B6bereiner%27s_lamp

[thecheat]

Oh, I FINALLY got some methanol. I went out side and tested it a little. The reaction this time lasted for a second or so! The thing is, that it's cool, and VERY wet outside, so I don't think I could get it self sustaining if I wanted it to... but anyways, just having it even act like it WANTED to run was great. Gotta find that other jam jar, the one I used was one I just jabbed a hole in with a screwdriver... ;)

[thecheat]

well, with a little help from a hammer, I flattened, and sharpened the edges of the hole. Guess what? it lit right up! heh heh... it's a pretty cool noise maker! Thanks for the help all! I'll have to play with these some more... (can't use all the methanol up yet though!)

[Mike Everman]

I keep my meths in a spray bottle. Keeps it nice and dry.