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I have been making this for a long time but a few years ago I searched a lot through out the web to get more information regarding this firework and was totally disappointed. Dan requested me to start a thread so I have decided to share whatever I know about this firework.

There are various types of ground spinners but this type consisting of a spiral paper tube casing, filled with composition and the casing is also consumed when it burns.

I examined several of this type from the market and guess that the composition is a modified flash like powder with Al filings. So some trial and error session and wasting lot of chemicals, I got a composition which works great for me.

The composition is as follows-

  • Barium nitrate –25% (-120)
  • Potassium nitrate-12% (-120)
  • Sulfur-7%
  • MgAl-12% (-200)
  • Al-powder-32% (< 45 micron flake, coated, mepco 999)
  • Al-filings-12% (30-80 mesh turnings from Al utensil factories)

 

 

Extreme care must be taken with this composition and all the safety precautions must be followed like flash.

 

Casing –It’s a vital part of this firework and if thin, burnt off all the composition at a time. Thicker tube blocks the flame and the hot gases as well and that may explode. A good quality virgin kraft paper should be used or it will tear off during spiraling.

I use 40 -50lb virgin kraft of 14”long and 5” width with the grain parallel to the length and dry roll my tube with a 6mm od Al dowel. I apply wheat paste about 1”at the end.

 

Filling-I usually use funnel and wire to fill the tube and always check for no air gaps and even filling with my finger tips. I leave off filling about 1”to one end of the tube which is glued and flattened to make it easy for spiraling. . I also prime the tip with a green mix +5% MgAl in nc slurry.

 

Spiraling- I tap the tube keeping it on a hard surface with a wooden mallet to flatten and bending it against the surface then make it spiral with patience around a1.5”od pipe or something like that. I put sufficient glue and either use a jig or tie with a rubber band that it cannot stretch out.

 

Finishing- After drying I open the rubber band and glued two card board discs, one of which has a circular bulging part at the middle for easy movement.

 

If you have any thought and idea please do share.

Here is a video of my spinners which I made last year.

 

 

http://youtu.be/pBbQZCoRTmo

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There is another sort of device somewhat similar to this called a rip-rap, grasshopper, or english cracker. A tube is charged with granular BP, and folded over onto itself many times. The powder in the bends crushes into a solid mass giving a delay, but when it hits the still granular BP it makes a pop or crack. This repeats itself for as many bends (ideally) you have.

 

The trick to making these is to dampen the paper tube and composition lightly. Do you think this may help to consolidate the powder and perhaps make the composition tube easier to bend and lay down? Given the composition, a little boric acid probably wouldn't hurt if this was ever tried.

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Really nice, thanks for sharing.

 

I also wondered about dampening them after loading to make them easier to twist around a former - with your method are they reliable or do they explode sometimes?

 

Some interesting discussion of jumping crackers over at UKPS including some photos of these old devices. Also called 'pin wheels', they used to be available in the UK before the blanket ban on items of 'erratic flight'. I had a few from old stock a few years back and they were a favourite amongst friends. A real shame they're not available anymore.

 

http://www.pyrosociety.org.uk/forum/topic/3073-jumping-jacks/

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There is another sort of device somewhat similar to this called a rip-rap, grasshopper, or english cracker. A tube is charged with granular BP, and folded over onto itself many times. The powder in the bends crushes into a solid mass giving a delay, but when it hits the still granular BP it makes a pop or crack. This repeats itself for as many bends (ideally) you have.

 

The trick to making these is to dampen the paper tube and composition lightly. Do you think this may help to consolidate the powder and perhaps make the composition tube easier to bend and lay down? Given the composition, a little boric acid probably wouldn't hurt if this was ever tried.

 

 

Though somewhat similar, I think there are also many differences between two in making and their effect as well.

The charged tubes of English crackers have some sharp bends and are tied with twine tightly as for blocking to pop loudly. It is just a multi pop jumping cracker and not so spectacular firework. It is also a bit dangerous as no one could know its proper direction of movement after igniting the fuse.

On the other hand the charged tubes of these spinners have no such sharp bends or blockings and if occur it would explode violently. The main technique of this spinner is to just make a circular coil with the charged tube that the direction of thrust is always tangent of that circle to rotate it continuously. It has about a limited area of moving after ignition which can be guessed previously. I think there are only a few such spectacular fireworks which contain just 8-9grams of composition.

Lancaster also stated to damp the charged tube, covered with a damp cloth for easy coiling in his ‘Fireworks Principals and Practice’ when discussing about pinwheel. It may help a bit but that discussion mainly deals with bp type composition which does not suffer Al and nitrate reaction in damp condition.

In my composition I always avoid damping, if any reaction occurs it cannot dissipate the heat easily as the composition is confined in a tube and the produced heat may promote the reaction and ruin the composition or something worse.

My trick of coiling works great for me and my local pyro friends. I never heard of any mishap during coiling.

I do believe that MgAl reacts with boric acid so I never use boric acid in a composition which contains MgAl.

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thanks ever so much for sharing this, and your time, realise now why you didnt post it on youtube, quite complicated and hazardous really.

I really like this effect and wanted to load a shell with mini ones since the first time i saw it, id love to make them but! Can the bano3 be subbed with something less toxic? Children and animals prevent me from using it i just wont take the risk.

The attractive thing with this is that anything that performs close must be pressed in a tube whereas anyone can make one of these with limited tools.

The coiling should be easy if you wrap the tube first, if anyone smokes, take a cigarette wrap it in a bank note and roll it up like a snail, when you unroll the fag ( for american ears ) it will be intact, a neat bar trick to score drinks.

 

Dan.

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Can the bano3 be subbed with something less toxic?

Dan.

 

I have tested it with KNO3 instead of Ba(NO3)2.It works! I have just felt some lack of brightness and beauty.

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thanks i seem to remember you could make it with all k nitrate, so 37 percent it is then.

This is the solution for people who want to make a fountain without a press, obviously you still have to be very careful using all k nitrate it will still be like flash with added friction risk due to the al turnings.

 

Thanks again

dan

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What are you talking about Dan? I'm not sure exactly what you're implying by it being a solution for people without a press, but it's no safer or suited to to ramming with all potassium nitrate than it would both potassium and barium nitrates. Half ass safety or techniques is going to put all of your ass in the hospital or jail
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im not talking about ramming it, following the instructions above , funnel wire, thin tube that burns off, no choke, the way i see it is not the way i said it, sorry should have been more clear.

Surely if you can funnel and wire this comp you can hand press it in small id thin paper casings like lancework.

 

Dan.

Edited by dan999ification
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  • 5 years later...

Yes, those types of compositions also work well. Check Lancaster or Westech Manual for more information and formulas.

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Westech has some good comps for wheels. I love that book for ground effect ideas!

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  • 2 years later...

Thanks for the help

I have tried and its working

Very nice

Please share a video of your product.i think we all are very eager to see the effect of that ... Specially I am....

I think Ben sir will agree with me 😁😁

Thanks....

Greetings...

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Catherine wheels should be made from a long (say 20" to 30") small diameter (say 1/4" -3/8" ) paper (newspaper??) tube. They were filled in a machine or hand jig with wire and funnel. The filled pipe was then damped, flattened with a tool and wound round a small wooden circular core. The outer end was nosed and fused with blue touch paper and the coil was secured with a single turn of 1/4" gummed paper. They took months to dry properly. They were sold with a label and a pin (for axle), when lit they should but usually didn't rotate. There is(was) a filling machine in Royal Gunpowder Mills museum hall.

 

Because they usually failed to rotate properly and because the Chinese could make drivers cheaper, a larger board with two or more drivers (like rocket motors but slower and longer burning) the more recent generation of wheels became available and more reliable

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