Be an Aeronautical Scientist: Make your Own Jet Engine for a few Pennies.

You can make a real jet engine for five minute's work and the price of a spoonful of meths - how cool is that?!?

I doubt there's a better way to re-use all those jars under the sink. Much more fun than a trip to the bottle bank.

Step 1: Materials and equipment.

Stuff I had lying around:

> Pasta sauce jar

> Matches

> A hammer

> A screw (it should have been a nail, but what the heck).

> A tin tray

Stuff I had to buy:

> Meths

Comments

[tobychan]

I drilled a hole in the cap of a 500ml Lucozade bottle around 8mm hole diameter. Then put in enough meths so that when you give it a shake, it just about coveres the inside of the bottle. I laid it on its side, put a flame to the hole and it went blasting off about 10 meters!
These engines were used in the V1 and V2 rockets by Germany. They would calculate fuel consumption and put exactly enough fuel in so that it ran out over London and the warhead would plummet down.

[lancealotx21]

So what exactly is a Meth?

[Kiteman]

<em>Meths</em> is actually methylated spirits - please read the rest of the comments.

[Kiteman]

<em>Meths</em> is actually methylated spirits - please read the rest of the comments.

[Mythbuster Kid]

Could you use rubbing alcohol?

[Kiteman]

If it's flammable, then yes.

[Mythbuster Kid]

Thanks.

[IronWill]

pretty cool, but I'm concerned about the potential glass shards being scattered IF it was to explode.
perhaps use a tin can or at least tape the glass container. so that it may break but not harm anyone.

nice guide though.

[Kiteman]

They don't explode - the big hole in the top means they can't build up enough pressure to do that.

The reason they break is because the temperature differences across the thickness and height of the glass causes fatal fractures.

[IronWill]

still not worth the risk too much meth is being used.
i am not saying your project is flawed, I'm giving a heads up to those new to it.

[Tim Temple]

If you want safety, rub the bottom of the jar on the sidewalk and suspend the whole thing from a cord. That way the bottom will blow off without causing any frags.

[Kiteman]

Hey, it's cool.

Everybody should assess their own risks, and if my project is too much for you, I'm not insulted.

[boom man56]

where did you git the Meths?

[Kiteman]

You'd need to ask your parents to buy it. See other comments for suppliers.

[The Dark Lord]

Have you tryed using this to propel a model rocket? ( Or other mode of transport?)

[Kiteman]

No - the burn cycle it very sensitive to symmetry, and tends to stop when you lay the jar on its side.

I do keep meaning to try adding an absorbent pad to hold fuel at the bottom of the jar to see if it works in its side then, so maybe you'd like to experiment for me?

[BrianRandleas]

I suspect that it is the air fuel mix that is killing it when you lay it on it's side. Try putting your hole near the top of the jar instead of the center and see if that works for you.

[Kiteman]

According to what I've read*, the burn needs to be symmetrical to be successful.



_{(* Which isn't much)}

[andy55551]

is there a way so it doesn't brake at the end?

[skatattookid]

i keep mine water cooled and also wrapped the glass in duct tape so if it does break its easy to clean up without getting cut. you can also just drill a hole in a can of broth and just use that.

[BrianRandleas]

That was my thought on using a metal can as well. A beer can or soda can pierced from the bottom instead of "Popping the top" should work as well. If you can find a way to pull the bottom into a cone shape that should also give better results if your wanting even negligible thrust. If you are using a metal canister you should also be able to lay it on it's side. More important than the shape of the flame is the air to fuel mixture you are obtaining.

[Kiteman]

Some people recommend standing the jar in cold water, but I would like, one day, to make a metal version, maybe with water flowing round heat-transfer pipes...

[orangetj]

or possibly have a undamaged lid freeze the jar with the meths inside and then swap lids? but then again it might get hot fast and break sooner

[ELITE-01]

I haven't tried this specifically,
but just as a reference to something I have done, unintentionally,
Rap a jar containing a candle in a cold, wet rag. The glass breaks pretty quickly, large cracks, some shattering, the works. so i'd assume that cold liquids, of any kind, with hot glass is a no go. 

[Aldeas]

Have you looked up the heller/lockwood version of the valveless pulsejet? That version uses a u shaped arrangement of the tube with and expanded combustion chamber to set up the harmaonic combustion pulse. one guy ran a gocart on one of these things using propane as a fuel.

[BitBoink]

Ya I remember SRL (Survival Research Laboratories) did a pulse cart back in the 90's. The pipe was glowing bright orange-hot right behind his head if I my memory serves well ... was insane looking!

[youkneephsycle]

about to go try this with a beer can replacing the jar, thet way it cant smash and the hole is a pretty good size anyway.

[BrianRandleas]

Here is an idea. Instead of "Popping the top" on the beer can, sacrifice one by popping a small hole in the bottom of the can instead. If you don't want to waste the beer use a soda can instead.

[Kiteman]

Oh! Let us know if it works, plus all the details - brand of beer, ~~flavour and alcohol content,~~ dimensions of can, dimensions of the hole, type and volume of fuel... ... and how about a video as well?

[Zaphod Beetlebrox]

I wonder if it work with a pop can. Or would the hole be to big.

[Kiteman]

I tried once, it just went woosh.

[Kiteman]

Although, you can get taller, narrower cans these days...

If you try it, let me know what happens.

[Zaphod Beetlebrox]

Thanks. saved me some experimenting. If I get one working I'll post a pic.

[CaptainMunz]

Hey guys. I made one of these one time and I found that a good fuel to use is "HEET". It's used to start your car when its really cold, so its quite flammable and vaporizes well. Good luck!

[Kiteman]

Thanks!

[vincent7520]

Great ! …
I particularly like the trial and error part that shows that all does not go always well as one may think with most inst' here !!!!…

Nice chimes in the background of the las video.
Where is it ? … US or England ??…

Best wishes.

[Kiteman]

England - that was the campanologists practising at the church in the middle of our town.

[vincent7520]

Aaah ! …
That was my first guess as I remember the bell choirs somewhere in England : doesn't exist much in any other place I visited.
his is very nice.

Now for the rocket science I hope that you won't feel hurt if I tell you that I would rather trust the americans for that matter …
But then again chimes are more beautiful and soul rewarding than anything than can be experienced on cape Kennedy … 

:D

[genericusername5]

would this still work it the jar was tilted on its side?

[Kiteman]

I don't think so - the shape of the flame inside is important.

Feel free to try, though.