37 replies to this topic

[qwezxc12]

There's been enough mention of this that I thought it deserved it's own thread.

Name of composition: Not sure..."AP/Hexamine Blue"? *see below*
Composition Type: Colored Star
Creator: Again, not sure...maybe me *see below*
Color/Effect: Luminous Blue

The Composition: (by weight):
Ammonium Perchlorate..........62
Copper Oxide.......................13
Hexamine............................10
Saran..................................11
Dextrin................................4

Any Precautions/Incompatibilities:
WARNING: Do not mix with Chlorates - may form the extremely dangerous Ammonium Chlorate by double displacement.
WARNING: Do not mix with non Di-chromate coated Magnesium - may heat up and decompose spontaneously.
NOTE: Do not mix or prime with Nitrates - may form Ammonium Nitrate by double displacement resulting in stars that are so hygroscopic they don't dry.

Procedure/Preparation:
Ensure all chems are reasonably fine. I coffee grind the AP first, then grind the remaining chems together, then screen them into the AP.
May be cut, pumped or rolled with 75/25 water/alcohol. I personally have pumped and rolled this comp. It rolls very well; just be sure your chems are fine. With the Hexamine as the sole fuel source, this comp needs little water to consolidate. I usually only need ~6% for pumped stars. It is slower burning compared to Ruby Red / Emerald Green. I've never made larger than 3/8" stars out of this comp.

Videos:
2in Mines (from the Ruby Red / Emerald Green thread)
Some more 2in mines
3in mines
4in shell (I had this in my shoot as a violet shell, but my notes do not show me ever making the violet stars. This may be the same blue as used in the mines, only primed for use in a shell, or I may have spiked it with a few % of Strontium Carbonate. At any rate, it looks close to the same and definitely has the same luminous flame envelope, so I included it)

*Name and origin notes*
This is kind of confusing. I originally got the idea for this composition from the first blue formula listed on Al's pyro page:
http://www.geocities...ompositions.htm

You can see it calls for "Perchlorate". The assumption is that it is Potassium Perchlorate because only the first color star comp (Red) specifies it by name, and all the rest just say "Perchlorate". His formula also calls for slightly differing amounts of Hexamine, CuO and Saran, as well as calling for Dextrin as an additional percentage.

So does substituting Ammonium Perchlorate for Potassium and tweaking some percentages around make it "my" formula? I didn't think so. But, it isn't "Al's Hexamine Blue", anymore either. So call it whatever you want. It's a nice blue with excellent color saturation.

[crazyboy25]

Yeah this is a really nice blue color last time I made them I rolled them used a lot of water and primed w/ bp all led to wet stars that burnt so slowly due to its high moisture content. I suggest pumping them.



You keep talking about how its so luminous why not call it luminous blue or something like that?

[pudidotdk]

Crazyboy, I'm sure you know, but the nitrate/AP reaction qwezxc wrote about could have something to do with your problem.

Qwezxc, does these stars need some form of special or hot prime to ignite?

Btw the "4in shell"... Didn't need to put a whistle on that one, the kids are screaming

[qwezxc12]

Qwezxc, does these stars need some form of special or hot prime to ignite?
Btw the "4in shell"... Didn't need to put a whistle on that one, the kids are screaming

Yeah, the kids loved the show. I'll make shells all day long for enthusiastic 5 year olds

Any way, to answer your question, as with all AP based stars, a KP based prime is called for. I usually use Bleser’s AP prime:

Potassium Perchlorate.....75
Red Gum......................12
Charcoal, Airfloat............9
Dextrin..........................4

But I substitute 3% of the charcoal for Dark Al or 100-200 MgAl for a little more heat , which basically makes it Bleser’s Strobe Prime minus the Potassium Dichromate.

Directions are to dry the core first, then roll about 1/32'' of this prime on all AP stars before more layers or final BP prime. He says to apply this prime with 6% NC lacquer to prevent nitrate leeching into the AP core, if BP meal based primes are used over this. I don’t…I roll this prime on, then roll a single, very dusty layer of my meal + Si prime and haven’t had a problem with ignition.

Once for a test shell, I used just the BP + Si prime with Red Gum as the binder and rolled it on with denatured Alcohol. The stars were already dry and I force-dried the prime right away in front of a ceramic heater. The prime was dry in a hour and I put the stars into a shell while they were literally still warm They worked just fine, but YMMV...

One very important factor, though. I’ve never made these for a can shell, only spherical shells…and I use plastic cases which are effectively moisture tight after they are sealed. I can slop wet gummed-tape all over the shell and those stars will stay bone dry inside. In a paper shell, the moisture from pasting may migrate inward and ruin the stars if you don’t seal the primes as Bleser directed.

[KAP]

Very nice blue, I guess I will be ordering some Saran in the near future also.

Good new thread idea, I have to take a shot at making your comets soon. I like your binder idea for those.

KP

[kwinchee]

Would it be possible you think to substitute shellac for saran?
International shipping kills

[Miech]

No. Schellack is not a chlorine donor. Probably this composition will also work with parlon, use somewhat more than you would do with saran. It might even produce an acceptable blue with pvc, but I doubt that.

[justanotherpyro]

So far I have had success with this comp using a BP/Si (10%) prime. After the star is dried I slightly wet it, prime, dry and repeat a total of 3 times. Here was one of the more interesting effects that a 1/2" star had. http://www.apcforum....iles/ApBlue.wmv I believe that there was a pocket of unmixed AP which caused the star to self propel but I 'm not sure. As far as why it crackled...I don't know. However accidental it was, it was really neat and I wish that I could repeat the effect w/o making go getters.

I have several from this batch which I will fire over the next few weeks to determine how much the AP/NO3 reaction proceeds and if it results in useless stars after X amount of time.

[qwezxc12]

Very cool. A shell of swimming stars of that blue would be very cool.

BTW, I rolled a pile of 5/8" AP blue over flash core for a 6in shell for my step-father's B-day. I hope to put it up in a week or so.

[GraafVaag]

Hi,
I recieved my AP last week, and now I want to make this composition. But the AP is in crystall form, and I have to mill it. I've got a steel milling jar with PTFE isolation in the lid, and glass media. I only used this jar for milling potassium nitrate yet. Is it possible to mill the AP in this jar? People told me that AP is sensitive to friction, while the MSDS tells me that it only forms explosive mixtures with combustible materials. (The known line for oxidisers)

So, is it safe to mill the AP in this jar when cleaned? The glass media remained OK till now, no glass pieces were found in the milled KNO3.

Another question, is it normal that hexamine smells odd? I never smelled hexamine before, so I don't know wether it should have a certain smell. It's just the +99% from KeteN.

[jacob]

I would not mill anything with glass media, much less AP, try to get some Stainless Steel, Ceramic, or lead. not to mention if you jar is bare steel it will rust badly, you could probably use a plastic food jar, or get some plastic pipe.

Yes it is normal for Hexamine to smell odd, kind of like old fish.

[GraafVaag]

Hi,
Why no milling with glass? I only mill pure chemicals in this jar. Will glass spark? For KNO3 it's no-problem if it does, but I don't know what it can do to AP.
The jar's stainless steel by the way, so no rusting here.

I don't want to use my lead media for the pure chems, since they tend to make the white powder grey after some hours of milling. That's why I chose not to use lead for this purpose.

EDIT:
I always mill my meal in a HDPE jar with lead media, but I can't use this jar here, since it's full of charcoal. That's my meal/charcoal-only-jar. As for pure chemicals I only use it to pre-mill the KNO3 I use in meal or charcoal streamers.

[jacob]

Ah I see,
pure AP (not in a mixture) is not sensitive to shock, friction, sparks, ect. I would not mill at all with Glass because even if it doesn't chip, it can and will wear down and contaminate your chemical with Glass dust, which may greatly increase the sensitivity of mixtures made with it, the amount of dust may be small, but it's definitely not something you'd want to have in a chem, and AP mixes are sensitive enough as is.

Oh and don't ever use Brass to mill AP, but I have no idea why, maybe someone can tell me?

[Miech]

It probably forms zinc perchlorate, which is an unstable explosive. Zinc is easily attacket by the acidous ammonium ion, under influence if water. You should be able to notice it by the smell of ammonia when this reaction takes place.

Any way, to answer your question, as with all AP based stars, a KP based prime is called for. I usually use Bleser’s AP prime:

Potassium Perchlorate.....75
Red Gum......................12
Charcoal, Airfloat............9
Dextrin..........................4

Wouldn't it be a better idea to leave the dextrin out of this compo, and use the red gum as binder? Not even all red gum has to be dissolved to make it a strong binder, and when dry after a relatively short time it should prevent the stars effectively from moisture. This should give a more reliable prime when another meal prime is applied over it, because there is no chance the nitrate can reach the ammonium.

[Frozentech]

Oh and don't ever use Brass to mill AP, but I have no idea why, maybe someone can tell me?

Tetramine copper compounds. Brass contains copper in alloy, copper ions and ammonium = bad news. There have been industrial accidents working with Ammonium perchlorate and brass / copper vessels and screens. It's one of those "better safe than sorry" cases.

Mumbles or one of the other Chemistry experts could probably say more about it.

[justanotherpyro]

It has been a little over 2 weeks since I primed some of these with a BP prime. They are still rock hard and lighting from a hard star gun shot. If they keep after a month then I think I'm sold on using a BP prime because I don't make shells and store them for any extended period of time.

[Mumbles]

Usually I apply a barrier prime (veline super prime), and apply the green meal coating with NC lacquer. Never had one star not light. The barrier and the NC protect the AP very well from nitrate.

Yes, frozen is right about the milling thing. Tetra amine complexes will quickly neutralize themselves due to their rather high hygroscopicity, but direct impact or friction can cause issues.

[GraafVaag]

Aight, an other problem on the AP milling subject..
I found some ceramic media lately, and now I milled some AP with it using a rubber lortone jar. When I opened the lid after 3h of milling I smelled a terrible ammonia smell. (Not as strong as from 5% ammonia though) Also the powder looked wet, this might be the cause of the problem.

Well, my plan is to lay a fine sieve over it, and let it stand outside for an hour or so, to get rid of the smell. Also it might be an idea to dry the AP crystals before milling more of them. Would the water have caused the problem? The jar and media were rather clean, I washed them with water twice before use. The crystals look quite like regular crystals, however there might be water caught inside..?

Any others having trouble with bad smelling AP? Suggestions?

[FREAKYDUTCHMEN]

Well stijn, I had some ammonia smell with Strontiumnitrate. wich you wouldn't expect either. I think you should try to mill it as dry as possible, so no reaction can occur.

Where did you find those ceramic media? You can pm me on pyro-stuff if you like

rené

[xxxjanusxxx]

Sorry for the bump, but has someone tried to change the saran for the parlon yet? I'm curious about the results, because we don't have any saran.