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  • 4 months later...
Posted

My favorite Kp blue is this:

 

Potassium Perchlorate 39

Copper(II) Oxide, black 37

Sulfur 15

Parlon 6.5

Red Gum 2.5

 

It`s the best amonium perchlorate free blue I´ve ever seen.

The only disadvantage is that you shouldn`t make cut stars over 7mm because of the yellow glowing cinder producing burnig of this stars.

As a priming meal with 10% MgAl or silicon is adequate. The burn rate is medium although it is a microstar mixture.

You must try this^^

  • Like 1
Posted
My favorite Kp blue is this:

 

Potassium Perchlorate 39

Copper(II) Oxide, black 37

Sulfur 15

Parlon 6.5

Red Gum 2.5

 

It`s the best amonium perchlorate free blue I´ve ever seen.

The only disadvantage is that you shouldn`t make cut stars over 7mm because of the yellow glowing cinder producing burnig of this stars.

As a priming meal with 10% MgAl or silicon is adequate. The burn rate is medium although it is a microstar mixture.

You must try this^^

 

Ooh, looks like nothing I have seen before, I will try it when I get more CuO. When you say they cannot be made larger than 7mm, does that mean that if they are bigger it affects the colour? Or do the glowing cinders just fall to the ground once the star has burned up.

Posted (edited)

I´ve the original formula from a excerpt in a german pyrotechnic discussion forum and replace the HCB by parlon.

And this seems to be from the rec.pyro thread.

I think you can replace the 2,5% red gum by even more parlon.

The high parlon percentage cause a doughy consistency when you mix it with acetone and create fibres when you cut it.

To solve this problem you can take a bit fewer acetone ore replace some parlon by PVC.

If the star is too big the glowing cinder stick on the star and the deep blue get lost.

Edited by Fluorescein
Posted

OK I made this, it worked, the blue was OK. However I've only made one batch and perhaps some tweaking would improve it.

 

KP_______ 60

Hexamine__20

Parlon_____10

Black copper(II) oxide__10

 

KP milled to dust, all sieved together, get the parlon tacky with acetone, stir, spread and cut QUICKLY. Very difficult to clear up as the dry product is rock hard. Firm in 30 minutes, rock hard in 12 hours. Lit as cut stars in a 2" ball shell simply from the meal break, without prime.

 

If you want a conventional gum binder it has to come from the hexamie 20, and be both a fuel and a binder.

So Hexamine 20 could become Hexamine14 and 6 red gum or SGRS or dextrin or.....

 

Softening a gum binder with a 25% alcohol in water mix would work but take ages to dry.

Posted

He're the original post, and a relavant discussion of the above comp. I think it was actually Optimus originally posting it.

 

Ever since seeing a commercial fountain with these kind of microstars, recreating the effect has been high up on my pyro to-do list...

 

This formula looked very promising, but I don't have access to HCB. I tried it anyway, and as expected, it didn't work very well.

 

Chinese deep violet-blue microstars

Source: Myke Stanbridge / Rec.pyro

 

Potassium perchlorate to pass #240 39.0

Black copper oxide to pass #240 37.0

precipitated sulphur to pass #240 15.0

Hexachlorobenzene (HCB) to pass #60 6.5

Acacia gum, a top quality fine dust 2.5

 

I asked Crazy Swede for some advice, and thought some others here might be interested in some discussion on the subject. I think it would be greedy to keep such good advice to myself, so here it is:

 

"I’m afraid the volatility of HCB is what makes that Chinese composition so special. They burn slowly and leave a big amount of slag from each star. Since the non-gaseous combustion products end up in one solid piece of slag, the flame is very clear and the CuCl*-radiation is so pure that the colour looks violet blue instead of deep blue.

 

Many years ago, I tried hundreds of experimental blue compositions in an attempt to duplicate this particular effect. I did not have access to HCB and tried instead to evaluate different cool burning fuels and flame expanding additives like hexamine, guanidine nitrate and nitroguanidine.

 

I don't have my old note books at hand and I can't remember the best composition (I never succeeded in getting the perfect blue anyway!) but the copper source was CuO, the oxidizer was ammonium perchlorate and the main fuel was red gum. Nitrogen rich compounds were added in such amounts that the composition only smouldered. Then small amounts of fine magnesium powder were added to bring the burning speed and flame size back to reasonable levels. Ammonium dichromate was added in small amounts to inhibit the corrosion process between ammonium perchlorate and magnesium. They were bound with NC solution.

 

The result was a star that burned with a violet blue flame and left one piece of solid slag. When shot in a mine the stars looked a little dim and the flames were rather small.

 

Since I didn't have a big interest in using them as micro stars I gave up on those compositions and turned to more conventional ones since they looked better in the air, even though their colour purity were lower."

 

So, it looks like I won't be able to get the formula working properly without using HCB. Has anyone else tried making this comp without HCB?

 

I've also tried using Burdick's blue strobe comp made into microstars. They look great, but they're not a deep blue/violet - more of a purple/blue.

 

Ammonium Perchlorate 63

Silicon, GE II 22

Copper(II) Oxide, black 10

Polyvinyl Chloride (PVC). 5

 

I'm now considering trying to tweak this formula to get the best colour. Obviously it's for a strobe propellant, so it makes sense to me that it could be made to function better as a coloured microstar. Perhaps increasing the percentage of Copper Oxide?

 

If anyone has any advice for me, I would really appreciate it! I would be a very contented pyro if I could get these deep violet/blue microstar fountains working properly!

  • 6 months later...
Posted

Has anyone used Shimizu Blue II with CuO? What are the results?

KP 66.5

Red Gum 9.9

CuO 13.4

Parlon 5.4

Dextrin 4.8

  • 10 years later...
Posted

Hello,

 

here is one of the blue that I created :

 

--------------------------------------------------

Blue BS3

 

- Potassium perchlorate (KClO4) : 58

- Phenolic resin (C10H13ClO3) : 7

- Saran (C2H2Cl2) : 14

- Lactose (C12H22O11) : 6

- Black II copper oxide (CuO) : 15

--------------------------------------------------

 

Each component are very fine, well mixed and binded with pure denatured alcohol.

Magnalium is outcast, and Lactose offset the fuel to give lower temperature.

The absence of Hexamine (in composition and phenolic resin) is a personal choice.

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