Can i use finer mesh Aluminum in this formula ?

[pyro5ive]

Can I use 225 mesh instead of 50-150? What will be the difference ?

 

 

 

https://fireworkscookbook.com/firework-recipe/comet-breaking-glass-orange-silver-dripping-sparks/

 

 

[lloyd]

'Dripping glass' requires fairly coarse aluminum, or it doesn't DRIP... instead, with fine aluminum, it burns bright-white hot, with few or short-lasting sparks, and burns MUCH faster.

 

The mesh-size of metals in formulae is important (very important!). It has ALL to do with the effect you want.

 

Lloyd

[OldMarine]

I've not seen any available aluminum that are listed as granular. Al classifications seem to be as arbitrary and confusing as rocket pound designations.

[Mumbles]

This document may be helpful as well. I think Eric made some incorrect assumptions, but it gives some more information on the effect.

 

http://pyrobin.com/files/breaking_glass_comet_analysis.pdf

 

The actual breaking glass Al I've seen is a little coarser than what is listed even. It is probably 20 or 30 mesh on the large end and mostly is coarser than 100 mesh. Firefox sells, or used to sell an aluminum listed as 50-150 mesh granular Al, which was entered into the passfire database, and is the closest available thing when entered. There may be some amount of finer grade Al included as well. The firefox stuff apparently isn't very coarse, so probably not even a good substitute. There was some of the better stuff floating around a while ago, perhaps from Tim Seekon or Karl Maerz.

 

One of these types of products, or a blend, probably gets closer to the real deal, if even available. This is just an illustration, I have no idea about the company itself.

 

http://micronmetals.com/products/al-110-technical-grade-aluminum-granules/

http://micronmetals.com/products/al-111-coarse-aluminum-powder/

 

Without the right stuff it's not going to drip. It'll probably just turn into a passable glitter with a long charcoal tail if atomized aluminum more conventionally sized for glitters is used.

Edited April 25, 2017 by Mumbles

[lloyd]

The particular formula he quoted won't make much of a glitter -- there's just not enough sulfur or sulfur compounds in it to generate much of that, and no 'delay agent' in there to delay the spritzels' breaking until they fall behind, either. That particular formula is basically a coarse aluminum 'flitter tail' comet, with nothing much to recommend it.

 

Lloyd

[OldMarine]

Is this similar in effect to FSFOY?

[wildcherryxoxo]

The particular formula he quoted won't make much of a glitter -- there's just not enough sulfur or sulfur compounds in it to generate much of that, and no 'delay agent' in there to delay the spritzels' breaking until they fall behind, either. That particular formula is basically a coarse aluminum 'flitter tail' comet, with nothing much to recommend it.

 

Lloyd

You've sparked my interest- about how much sulfur is required to make a glitter glit?

[lloyd]

Well.. that was a sort of "seat of the pants" appraisal on my part. I'd have to compare a bunch of formulae to see if there's any 'cast in stone' threshold amount. Generally, glitters have a surplus of sulfur or sulfur-bearing compounds as compared to clean-burning formulae.

 

For instance, my 'Buttered Popcorn Glitter' uses ordinary Meal-D as the flame package, with some sodium bicarbonate to yellow the flame and slow the burn rate. But without added antimony sulfide, it just burns like dirty, slow, yellow-flamed BP.

 

In that sulfide-free form, it leaves a good bit of ash, but not any significant spritzels. When you add the extra Sb2S3, it leaves large globular spritzel flashes behind.

 

Lloyd

Edited April 28, 2017 by lloyd

[wildcherryxoxo]

But you said the formula doesn't have enough sulfur, and that it won't glitter.

 

wouldn't it be wise to FIRST do a little comparison before making such a bold claim? A real amateur might take your advice as gospel, even when it's just "seat of the pants" rambling, and potentially untrue.

[lloyd]

First of all, I did NOT say it would not glitter; I said it wouldn't "make much of a glitter, if it glitters at all."

 

Sigh.... did YOU try it? I'm not the world's expert on such formulae, but I've got about five decades of making them, and seeing them burn... three of those decades commercially. So, it's my 'best guess' that it will be a paltry glitter, if it glitters at all.

 

OF COURSE I might be wrong. I make many such mistakes, only to find I'm 'spitting into the wind'. On the other hand, you seem to be more entertained by looking for others' mistakes, than trying to make sure the data is right.

 

Why don't you try it, and report to us? ("Honestly" would be a good way to do that.)

 

Lloyd

Edited April 28, 2017 by lloyd

[wildcherryxoxo]

Saying "not much of a glitter, if at all" is, practically speaking, to say that it's not going to glitter. But I'm not here to argue wether or not the formula will or won't, I'm just pointing out that your claim was made before doing any sort of research or forethought.

 

50 years making and testing glitters and you can't tell me if 6% sulfur is enough.. I have less than half that experience and I can tell you that 6% sulfur works in plenty of my glitters.

Edited April 28, 2017 by wildcherryxoxo

[lloyd]

No... I try to use language precisely.

 

You did just succeed, though, in describing how bad an effect you're willing to be satisfied with. That tells me a lot about you.

 

Yeah... there certainly ARE 'glitter' formulae published that use less than 6% sulfur -- but when it's that low, it's accompanied by a significant proportion of a delay agent... which this formula did not have. Fluorine compounds can replace the sulfur (like when cryolite is added both to color and to delay a glitter).

 

So...Now I know you're willing to 'excerpt' facts (Lie, with partial truths...) in order to make your points, and I now know you are satisfied with sub-standard effects.

 

Those traits seem to fit well with your user icon...

 

Lloyd

[wildcherryxoxo]

Lloyd, I had written a response but I'm drawing the line at personal attacks, to me that says VOLUMES about a mans character. When someone swoops to petty jabs about someone's appearance during (what could be) a healthy discussion, I'm out.

 

I'm drawing my line, it's just the way I am.

[lloyd]

Heh! We can see from your icon "the way you are"!

 

Anyone who presents their public image in a way deliberately seeking to offend, regardless of the manner in which they do it, is personna non grata in just about any social group.

 

<BSEG>

Lloyd

Edited April 28, 2017 by lloyd

[MrB]

Heh! We can see from your icon "the way you are"!

 

It is a troll, and rarely contributes anything but spite. If this forum had a "ignore" feature, i'd have used it in one single instance. Don't pay any attention to it.

 

And for reference. I tried the comp. Granted, i don't have 225 mesh Al, but substituted 200-250 instead. No glitter. Pretty much a silver star, with slight orange trail.

[lloyd]

MrB,

I knew all the 'troll' stuff about 'it', and I'm loathe to abide those sorts of trouble-makers, too.

 

For your testing -- thank you. When I am guessing (and I was this time), it's nice to have corroboration.

 

Lloyd

[Maserface]

That's interesting mrb, but that's probably expected since the formula calls for coarser material.

 

What size comet did you pump? I've heard that some of the "breaking glass" formulas tend to work well at a given size and not very well at other sizes.

 

I've made and shot a bunch with different aluminum, the base formula is proprietary, but it gives you an idea. This was made with roughly 325 mesh aluminum

 

[MrB]

2" wide, about 2" long. Made a couple, cut one apart this morning, just to check that they really were dry, and shot another one. Same result. Seams to burn faster then intended.

[DavidF]

Guys, the sabre-rattling draws attention away from the subject at hand. The term dripping sparks got changed to glitter. Then the subject of delay agents was introduced. I don't know which formula was being dismissed as mediocre, Ned's or Eric's. Mr. B used 200-250 mesh aluminum because he didn't have 225 mesh? Where is 225 mesh even mentioned to be used? Maserface's nice glitter comet bears no similarity to the effect mentioned by the OP.

 

I'm wondering: if aluminum burns in an offboard reaction after separating from the comet, is that automatically a glitter? Does the fact that there is a delay automatically mean that a delay agent was used? I thought the spritzels 'flash' in glitter after the sulfide melt burns off. Is the slow offboard burning of aluminum the same thing as glitter flashes, in your opinions?

 

Ned's famous palm tree shell makes use of very coarse (grape nutz) titanium sponge. The burning titanium falls through the air. I've made C6 comets with that titanium. The titanium seems to ignite after a delay. In my simple way of looking at it, the 'dripping sparks' comet- the subject of the thread- works in a similar way to Ned's palm tree comets. I'm no expert, but neither of Ned's comets seem like they would be called glitter.

 

There's all kinds of interesting stuff to talk about here- if we want to. I do!

[MrB]

I'm not entirely sure, but somewhere along the first few words in the topic starter, there was a mentioning of replacing the Al with finer stuff, and while i didn't have anything that specifically matched the size, i had what i suspect amounts to the same stuff, and tested it. It would be my suggestion that this is not a viable alternative.

 

Can I use 225 mesh instead of 50-150? What will be the difference ?

[Maserface]

Davef- I should have been more clear, the glitter comet I posted is of a "breaking glass" formula, which calls for coarse aluminum, but I tried fine aluminum instead, and that video is the result.

 

I made the same formula three times, with three different aluminums, and got three results.. Unfortunately only one video

[Mumbles]

First off, I'm going to move this to a different section since it seems this conversation is going to continue. The original section is really more of a database for tried and true compositions, and not general questions and discussion anyway.

 

David, bringing up the off-board reactions brings up an important point I feel that is going to underlie this conversation. I was having a conversation with Maserface the other day about this. To me, there is a subtle functional difference between a true glitter and something like a firefly, brocade, certain streamers with delayed metal ignition, etc. Just for simplicity, I'm going to call the latter the firefly effect for the purpose of this discussion They often can resemble each other, and probably can both manifest themselves in the same comet. Glitters are believed to function by a sulfide melt being formed in the comet, coating the metal particles, and being blown off the surface. After some delay through the air the sulfide is oxidized to sulfate, at some threshold of reaction and temperature, the particle explodes in a flash of light. Fireflies and other delayed ignition stars probably function on a similar principle, however the functional difference is that they rely on atmospheric oxygen to complete combustion of the metallic particles. Whether this is purely due to larger metal particle size or combined with somewhat different formula requirements can be discussed. The telling evidence that there is a difference between these two is that you can make the firefly type effect happen with Ti and FeTi, whereas to the best of my knowledge they do not work in true glitters.

 

The real breaking glass effect is probably a mixture of both of these. The dripping appears to be slightly delayed, and the is clearly not a flash like you see with glitters, though there is some of that in the tail.

 

While I haven't felt the need to join in, I have been following this thread and thinking about the things discussed. I looked through a bunch of formulas to see if there were any trends or rules that might pop out. I went at it from the view point of sulfur makes a formula glitter, delay agents just modify them or makes them better, not makes or breaks the effect. A bad glitter still glitters. It might be worth noting that barium nitrate acts as both an oxidizer and a delay agent. It gets a little complicated trying to account for both sulfur and antimony trisulfide. Win39 tells us that Sb2S3 alone is sufficient. Most glitters had at least 16% total sulfur content (just S + Sb2S3), though that varied up to over 20% to down to 10-12%. Winokur 11 is one the lowest I found, which has 10% sulfur, though also contains a healthy amount of barium nitrate, and 1% iron oxide. Winokur 12 has low levels of both sulfur (8%) and antimony trisulfide (5%). Winokur 31-38 also show low levels of total sulfur with different additives. 10-12% is probably the lower limit of functionality.

 

Conversely, firefly effects require less. Rarely do they use over 10% sulfur actually. They're typically all sulfur, and tend to be in the 6-10% range. Larger particles have less surface area, so it could be argued that they need less sulfide melt. Since atmospheric oxygen may be required to complete the combustion you also don't need enough melt to totally consume the particle, just ignite it after a delay. The reason is up in the air, but the amount of sulfur certainly appears to be lower. It is worth noting that the collection of these sorts of formulae is much smaller than for glitters.

 

For what it's worth, I took Maserface's comment to mean that he's using the real breaking glass base formula. It clearly works with a finer aluminum, though without the characteristic drip. Ned's formula resembles the effect, though not nearly as drippy. It might just be the Al used of course, but could also be two different ways/formulas to achieve a similar effect. More than one way to skin a cat. I included videos of both below.

 

Neds:

Real Breaking Glass:

[DavidF]

Thanks Mumbles, that was very informative. I wonder if- for pyro purposes- granular aluminum must be atomized spheroidal. It would be easy enough to make some raspings in the particle sizes quoted, if the angular shape didn't matter too much.

 

EDIT: JHere's Ned's palm tree shell with titanium . The titanium falls just like the aluminum in Ace's comets, but definitely lacks the 'drippiness'.

Edited April 30, 2017 by DavidF

[lloyd]

David,

In answer to that last, I can give you something definitive, instead of just a guess.

 

We were bequeathed somehow a 100lb drum of 80-mesh truly granular aluminum which was obviously made by some machining or 'rasping' process.

 

The particles were not long shavings, but small irregular particles with visibly 'cut' edges all-around, and roughly as long (maybe up to 1-1/2x the length) as their narrower middle dimension. They often had angular 'sharp' ends or corners, just as you'd expect a machined particle to have.

 

It worked fine in non-glitter 'tail' effects, and I tried it once in a slow sulfide glitter. It was too slow, with the flashes too large, too sparse, too far behind the head, and accompanied by a flitter tail, also; but it did glitter.

 

Lloyd

Edited May 1, 2017 by lloyd