Simple reed for a simple squashed tube pulsejet

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Mark
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Simple reed for a simple squashed tube pulsejet

Post by Mark » Sat Jan 31, 2004 6:45 am

http://cgi.aol.ebay.com/ebaymotors/ws/e ... 2457031552

I once toyed with the idea of using my Dad's old Air Force captain bars for a small retainer similar to the simple single bar retainer above.

http://cgi.aol.ebay.com/ws/eBayISAPI.dl ... tegory=588

Maybe use a lieutenant bar for a smaller jet, depending on what rank you want to enlist. The major problem would be forming/reducing the straight tube into a typical Dynajet shape perhaps.
In general, I try to use common things around the house to fabricate with. It's fun to be on the hunt like some private eye looking for an infinitely simple object to work with. That's why jam jars are fun to me, they are masters of simplicity.
Mark

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Post by Mike Everman » Sat Jan 31, 2004 9:20 am

I know what you mean. I look at every common vessel in a different way now. Check out these two vases. I wanted to play with annular exhaust and these were perfect. It pulsated as shown, but lazily, probably the inner one rattling around killed it. I propped one up on a salt shaker, but I need to wire this all together and get the cc volume up.
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Post by Mike Everman » Sat Jan 31, 2004 5:04 pm

Got a whoosh loodle out of it, have to try more positions...
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Post by Mark » Sat Jan 31, 2004 6:13 pm

That little jar to the far left is about the same size as the jars I use that run so well. And they beat the air a little faster, being shorter I suppose. An enchanting bit of sound and energy for a meager eyedropper worth of fuel. And the price is right. Just a speck of boric acid powder makes it a firefly of vivid green in a darkened room. You might try some copper sulphate or other colorants. I wonder if vanilla flavoring would add to the effect? I guess a lime scented combustion would have to be green, what was I thinking.

Wouldn't this be a funny book to leave laying around your boric acid and jam jars, if the police came to investigate the loud noises in your garage. http://cgi.aol.ebay.com/ws/eBayISAPI.dl ... gory=29228

Here's a boric acid jar, hmmm.http://cgi.aol.ebay.com/ws/eBayISAPI.dl ... gory=10854

And something stranger perhaps. By the way, I wonder if you could use a ceramic eye for something? It would certainly be Salvador Dali-ish if you incorporated it into a project somehow. Anyone ever see Andalusian Dog? A bunch of disjointed thoughts, sort of like the way my mind "works." http://cgi.aol.ebay.com/ws/eBayISAPI.dl ... gory=15911

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Post by Mike Everman » Sat Jan 31, 2004 8:48 pm

Mark, that little one is a spice shaker. I cut a 3/8" hole, might need better sealing since it's just metal on the glass lip. Nothing seems to go today. May be humidity.
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Post by Mark » Sun Feb 01, 2004 7:24 am

Mike Everman wrote:Mark, that little one is a spice shaker. I cut a 3/8" hole, might need better sealing since it's just metal on the glass lip. Nothing seems to go today. May be humidity.
Some days are like that, summer in Florida depletes most of the vim and vigor of jam jars. You can find jars that size/shape that hold mustard or capers or what I have is from the hospital, tiny newborn baby formula bottles, the caps screw on well, but it's tricky to get them to go on straight, a bunch of mini threading, but they seal very well. There's a dozen angry bumble bees on crystal "meth" in every jar. Maybe one or two hornets as well. Cold dry air works best. The mustard jars work but if you overtighten them, they leak air around the cap.
I'll send you one of my treasures if you like. I hate to think how many are thrown away each day.

I still haven't located any good steel jars on the web as of yet for a reasonable price. There must be a few companies that are making what we need, if we just knew who. I found these odd metal jars, but they aren't located in the U.S. and I don't know if they would be too leaky around the coarse threading. Sometimes though, a jar can breathe a little around the skirt and it is beneficial.
http://www.surplusandoutdoors.com/ishop ... cr759.html

Mark

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Post by Mark » Sun Feb 01, 2004 4:24 pm

Mike Everman wrote:Mark, that little one is a spice shaker. I cut a 3/8" hole, might need better sealing since it's just metal on the glass lip. Nothing seems to go today. May be humidity.
On a jar like the spice jar, I wouldn't go over 5/16ths nor under 1/4 inch for a hole. If it's hot or humid or both, what normally works will work better if the hole is slightly smaller. If you have a leaky lid, maybe a smaller hole would compensate somewhat, but tis best to have an air tight lid!
It's a death sentence for little jars if there is the least bit of leakage from an inferior lid. If it doesn't puff after you shake the jar with alcohol and take your finger off, it's going to be the school of hard knocks. I have some little jars that are 3 and 4 inches tall and about the same proportions as the spice jar you have. Little jars are fun and worth the effort of having to drill that one hole. I use to hate to even do that before I bought a lathe, trying to determine the exact center and make the cut neat. Now I just pop them in my mini-lathe and chuck the lid and spin it against a stationary drill bit held in the tailstock. I bought one of those tree step drill bits too, http://cgi.aol.ebay.com/ws/eBayISAPI.dl ... otohosting but most of the time I just use a countersink and eyeball it.
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Post by Mike Everman » Sun Feb 01, 2004 10:21 pm

As to sealing, I found some "liquid electrician's tape" at home depot, I'll try coating the seating area in the lid.
As to good steel jars, I'm on the right track, if propane cannisters are anathema, that is.
The best so far is under the category of "stainless steel utensil holders", some really nice ones I saw today. About 2qt., thick flat bottom, rolled lip at the opening, I'm guessing 1mm thick material. For attaching the intake disk, now I'm looking for v-band clamps, or I'll have to make one from a regular band-type.
Found a really good ceramic vase at the thrift store yesterday with about a 6" dia globe at the bottom and a 1.25" dia pipe extending up about 12" from there. Makes a good loud "bark" (as you would say), then luffs very quietly for 20 sec or so.
Mike
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