"Spider" Stars - burning too quick?

[stix]

I've made a batch of 1/4" (cut) spider stars from this comp:

 

KNO3 : 55
C : 27.5
S : 10.7
Dextrin : 6.1
Lampblack : 0.8

 

After about 9 days of drying they seem to have dried very well. I did a simple ground test of one of the stars and it spun around and almost took off!!... It was not what I was expecting. I thought it would have burned slower.

 

I will do a star mine test (3/4") and I can imagine there will be golden streaks in the air, and look really good, but they certainly won't burn to apogee and come down again. I also made a small pressed comet and I think that it will give better results.

 

A slower burning charcoal perhaps would be better - and screened instead of milled?

 

Cheers.

[VikingPyrotechnics]

Spider shells need to be broken very hard, so your stars should be fine for this type of shell

[stix]

I'm still working my way up to the "shell" stage. I'm just trying to work out the basics of small stars. Hopefully in 6 months time or so I will have gained enough info and experience to get there.

 

Thanks, Cheers.

[nater]

Spiderweb stars are supposed to burn quick. They are intended to ignite from a flashbag burst and leave streaks in the sky, burning out before they droop. When fired as a flight or multiple breaks, the pattern resembles a spiderweb.

 

They may not be the best choice for a mine with 1/4" stars. You could try it with the stars you have, but you may want to try larger stars or a slightly slower comp. What effect are you wanting with these mines?

[stix]

Spiderweb stars are supposed to burn quick. They are intended to ignite from a flashbag burst and leave streaks in the sky, burning out before they droop. When fired as a flight or multiple breaks, the pattern resembles a spiderweb.

 

They may not be the best choice for a mine with 1/4" stars. You could try it with the stars you have, but you may want to try larger stars or a slightly slower comp. What effect are you wanting with these mines?

 

Thank Nater.

 

Ok, it seems as though it won't be a good effect from a 1/4" star mine. But I'll do it anyway. I'll press another comet or two, and I'm sure that will be much better.

 

What effect am I wanting?... Well, I'm sure you already know... "streaks in the sky, burning out before they droop" sounds good to me but I am not there yet.

 

There is a lot of work to be done from my end before that ever happens - I probably get a bit ahead of myself at times but at least I admit that I don't know, and therefore ask the questions.

 

Cheers,

Edited February 15, 2015 by stix

[schroedinger]

In a 3" 10 mm pumped spider stars are a good size. In a 4" they are a little bit too small.

[stix]

In a 3" 10 mm pumped spider stars are a good size. In a 4" they are a little bit too small.

 

Yep, thanks schroed's all good - I'm learning every day. I've pumped one good 17mm comet and will do some more with some left over half wet mix. Slowly, slowly is my motto. It all seems simple, but it's absolutely not!!!!

 

Thanks, and much appreciated.

[pyrojig]

You can slow the mix by adding 50% screened mixed comp to it, or adding more charcoal( to dilute it) . My comps when milled do the same, burn almost explosively . lifting off the ground . Quite a scare when you didnt expect that. Seem to be good chasers lol.

If you are to mill, I would mill only for a very short time( depending on your mill 30-60 min max. ) ALso the mix can be divided = pull half the ch out and mill the comp shortly, then screen in the other 1/2 of the ch .

If making comets you can paste them leaving only a 1/8" of the end showing for ignition . This slows the burn a bit.

 

Just a couple approaches . As said , the comps is designed to burn very fast for the effect.

[Mumbles]

I assume that formula is one of the ones that Mike Swisher has shared? I'm more familiar with them when they're in the original parts instead of percentages. Anyway, I don't mill that particular formula. Even screen mixed it burns fairly rapidly. 1/4" stars still will burn quickly, and are not well suited for shells over probably 2". I've made a lot of these types of compositions, since spider shells are one of my favorites and an area I'm pretty good at. I use one of the Swisher provided formulas for screen mixed, and some formulas from Ralph Degn (BAFN 3) for milled stars. The two formulas are pretty similar actually. The screened do burn quite fast, so they're made a little larger. I tend to use 1/4" to 3/8" cut stars for the inserts (1.75" ID), and 5/8-3/4" cut stars (4" shells) or 1" comets (5" shells) for full sized breaks. I have some videos if you'd like to get a feel for the burn times of screened mixes at least.

 

They'll still be fine. It may not be exactly what you want, but live and learn. They'll make an attractive small mine still I suspect. To get the most out of them, you might consider using a slightly shorter tube. This will give a wider spray of stars, which will probably be a little more attractive since they will burn out pretty quick. Lift them hard as well.

 

If you want something that burns slower try chrysanthemum 8 or tigertail.

[nater]

http://youtu.be/oCccx7yr-Ac

 

Here are a few 1/2" stars which have not been primed and were just lit on the corner rather than trying to get the whole star to light at once. Both were screen mixed only, bound with dextrin and pressed with an arbor press. The first is C6 with 10% FeTi and the second is the same Spiderweb comp posted above. You can see it is just a little faster than the C6 comp and both take fire easy.

[stix]

I assume that formula is one of the ones that Mike Swisher has shared? I'm more familiar with them when they're in the original parts instead of percentages. Anyway, I don't mill that particular formula. Even screen mixed it burns fairly rapidly. 1/4" stars still will burn quickly, and are not well suited for shells over probably 2". I've made a lot of these types of compositions, since spider shells are one of my favorites and an area I'm pretty good at. I use one of the Swisher provided formulas for screen mixed, and some formulas from Ralph Degn (BAFN 3) for milled stars. The two formulas are pretty similar actually. The screened do burn quite fast, so they're made a little larger. I tend to use 1/4" to 3/8" cut stars for the inserts (1.75" ID), and 5/8-3/4" cut stars (4" shells) or 1" comets (5" shells) for full sized breaks. I have some videos if you'd like to get a feel for the burn times of screened mixes at least.

 

They'll still be fine. It may not be exactly what you want, but live and learn. They'll make an attractive small mine still I suspect. To get the most out of them, you might consider using a slightly shorter tube. This will give a wider spray of stars, which will probably be a little more attractive since they will burn out pretty quick. Lift them hard as well.

 

If you want something that burns slower try chrysanthemum 8 or tigertail.

 

That's correct, the formula is one that Mike Swisher shared that I got from an old post on cutting stars.

 

The thing that threw me about the burn speed was after I milled it - I tested a small pile and it went whoosh... a huge amount of golden sparks. Ignorantly I assumed that the final effect would be similar. Lesson learnt.

I will try C8 or TT as suggested and also screen the comp instead of ball-milling.

 

And yes, please post links to the videos. Cheers.

 

 

http://youtu.be/oCccx7yr-Ac

 

Here are a few 1/2" stars which have not been primed and were just lit on the corner rather than trying to get the whole star to light at once. Both were screen mixed only, bound with dextrin and pressed with an arbor press. The first is C6 with 10% FeTi and the second is the same Spiderweb comp posted above. You can see it is just a little faster than the C6 comp and both take fire easy.

 

Thanks for that nater, they look good. Unfortunately I can't do that test yet as I only have the one comet . I'm going to have to start making bigger batches.

 

Cheers.

[Mumbles]

I have 2 decent ones. Both use the Swisher formula IIRC. The first is from competition, and uses 1" comets in the final break. I didn't break the inserts hard enough. The second uses 5/8"-ish cut stars in the final break. I broke most of the inserts fine, and you can see the overlapping spiderweb effect. The final break was sort of anemic, but incidentally rather spidery looking, since I used a slow flash instead of the normal 70/30.

 

 

[schroedinger]

Nice shells mumbles. The BS on the first shell where 1" never thought that those would burn up fast enought for a 5" BS.

Alsoo did you buil the beraq on the channel, really good job.

[stix]

Thanks for sharing those Mumbles. I loved the final break on the first video. But the lingering and wispy tendrils of red fire dust on the second was the standout for me. [EDIT] you cut the vid too short.

 

Is that "lingering red effect" to do with the addition of the carbon/lamp black? (compared to TT that has no carbon black) If so, is the 0.8% in the original Swisher comp correct? 0.8% seems like a small amount, or did you add more?

 

With my remaining spider comp I've pressed two more comets, so I'm going to do a static burn test like nater did on the one which is dry (I'll post the video here). As suggested I'm just starting a comp of TT - half will be ball-milled and the other will be screened.

 

Cheers.

Edited February 18, 2015 by stix

[schroedinger]

No real worth to try those glitter comps static, test it from a star gun

[stix]

No real worth to try those glitter comps static, test it from a star gun

 

Yep Schroedinger, I absolutely will be doing a "proper" test from a star gun (2 comets when dry) and small 1/4 inch stars. I'm very much looking forward to that!!

 

The "worth" is to provide a comparison with what nater posted, who was kind enough to take the time to post it. Perhaps not greatly scientific, but a general observation is still a worthwhile endeavor.

 

btw. I didn't think that spider was a glitter comp, ie. no metals. I thought it was of the category charcoal comp.

 

Cheers.

[schroedinger]

Well thats propably a little up to discussion and point of view.

But the big two categories are color and fire dust (aka. Glitter type, or tailed). Which can be broken down into more au categories, like colors, oxidizer based, type of tail (charcaol, metal).

[FlaMtnBkr]

Glitter and charcoal are completely different effects?!

[stix]

Ok, the static test (try not to blink, or you may miss it).

 

Static test. 17mm (approx. 5/8th") pumped comet (spider composition)

18.7mm long, 4 grams, approx. density 0.94g/cm3

 

http://youtu.be/YXjYd0O1MoY

 

I'm glad I stuck the base to some aluminium tape and then to the concrete otherwise I'm sure it would have become airborne.

 

Yes, hardly scientific I know, but it certainly burnt a lot quicker than the test nater posted. Mine approx. 2 secs and naters, which was a smaller comet, burnt for around 5 secs? I wonder why the big variation - density?

 

I did like the amount of sparks - I imagine when the outer is wrapped in kraft and shot hard from a star gun, it will produce a nice long tail.

 

Cheers.

[stix]

At this point there is still no resolution to my original question "Spider Stars - burning too quick?" The reality is that they do!!

 

From the comparison video of naters and mine, there is a vast difference. Why?. Nater, I'd much rather slower burning like yours than mine - what charcoal did you use?

 

I've gone back to basics and mixed some TT (44/44/6/6) as mumblers suggested. Half the mix was screened, the other was ball-milled. It's only 5 days into drying but I can already tell by burning a few small bits that it's going to be fast.

 

The only conclusion that I can come up with is that my paulownia charcoal is the culprit. I have read that others use "white pine" for charcoal stars - I can't get that, but I'll investigate slower burning alternatives.

 

Cheers.

 

[schroedinger]

Stix if you still think they burn too quick, just up the charcoal content. But spider stars are designed to burn that quick. They are supposed to deliver the effect in 1-2 seconds.

[pyrojig]

II agree with Schroedinger, up the ch content to slow the burn. I would change the Ch completely to a slower variety, at least to a pine. Reduce milling (or forget about milling ......I dont) , and screen mix the comp. As said above, it is the desired effect to burn out quick. I would fire these in a shell before judging them on a "ground test" . Break them simi-hard , and see if they dont amaze you!!

[nater]

I used commercial airfloat charcoal and the comp was just screen mixed. I only use hotter charcoal for lift and burst and use commercial airfloat or Southern Yellow Pine for everything else.

 

The stars should burn a little faster in the air too. Once built into a shell and primed, they should light all at once instead of from the edge. I would fire your stars and see how they look in the air before considering any changes.

Edited February 25, 2015 by nater

[Mumbles]

....

 

The only conclusion that I can come up with is that my paulownia charcoal is the culprit. I have read that others use "white pine" for charcoal stars - I can't get that, but I'll investigate slower burning alternatives.

 

Cheers.

 

 

 

Ah yes, this would be the issue. Unless you specify, most people will assume that you're using commercial airfloat or something similar. I'd save the paulownia for when you need speed.

[stix]

Great! - thanks guys. Looks like the time has come when I'll need more than just one type of charcoal. I guess that means I'm learning something, so all good.

 

I'll try "plum" as I have a tree in my back yard. I tried it when I made my first test batch of bp some 6 months back and considered that it was too "sparky" and burnt too "slow" - but now this seems like the ideal candidate so I'll give it a go.

 

Cheers.