mesh size affecting tails question

[dan999ification]

I plan on making some silver willow stars, as I understand ti can be added without affecting performance too much. my ti is 0-100 mesh sponge, I intend to use up to 20% I expect most of the finer particles to be burnt up in the star and affect the performance. I have 60-300 and 200 mesh mgal and 250 mesh atomized al, the comp I have specifies 0.1mm spherical al and does not specify mgal mesh though I expect 200 mesh and larger to be useful in tails unless there is a high enough percentage for some to be thrown from the star. questions: will the sub 200 mesh metals be burned in the stars flame and be useless for tails leaving only the larger particles for the tail, or will I still get some fine firedust with the coarse? how will adding even more fine metals affect the burn time of an already fuel rich star? which prime and method should I use? are half inch pumped stars too big for 3" canisters? im having trouble getting my head round what exactly will happen here,I don't want to waste chems without some recommendations and must find an alternative use for this very fine ti. my charcoal stars will all get a few percent but it has to have a use other than just priming. does anyone know of star comps that use very fine ti? dan. Edited September 30, 2013 by dan999ification

[Shadowcat1969]

Well, I use my granular -40 +300 mesh Ti in Willow Diadem and that seems to work pretty well. There's only 3% of that though. 5% each of 30-60 mesh FeTi and 40-325 mesh FeTi also go in there.

 

Hopefully that helps, at least a bit.

[Pyroboy]

Maybe you can give some further information on the comp you are going to use. Its not easy to say what impact metal powders have on the perfomance, without knowing if its a metal or charcoal based comp for example.

There are some silver willow formulas round this forum or on skylighter that uses Al flitter or at least coarse Al, why not trying one of this?

[dan999ification]

silver willow:

kclo4 52

mgal 24

al 10

sulfur 3

charcoal 5

dextrin 6

pump with 65/35 water alc, you could probably cut these but rolling my be problematic due to the high metal content.

 

I want to add the fine ti in the hope that it will increase the density and length/of the tail and add more fine firedust, my fears are that the stars will not produce any firedust and just smoulder forever instead if I add the ti.

 

shadowcat: that sounds promising. I know the comp, that is basically what I want to try to create with this metal, a very fine grained dense firedust star that has a long duration, like a metallic tigertail. maybe adding it to charcoal stars would be the best option but I tested fine mgal in charcoal stars and most just turned into red hot ballbearings in the proportions I was adding.

can I replace half of the charcoal in streamers? with this ti or can I add 20% to the complete comp?

the trouble im having is finding a way to get the titanium to catch fire and leave the star still burning, I seem to think that the only way to do this is by using it in a comp that is already fuel rich but not too hot in which case the silver willow I want to use may not be the best option as a base.

how about any titanium glitters?

is it best to look for using it in subtle effects?

can I use a 50/50 mix of this fine metal and an oxidiser with careful prep [ wetting the oxidiser with the binding liquor before adding metal, or just diapering?], I know some comps using al in the same way.

 

dan.

Edited October 3, 2013 by dan999ification

[psyco_1322]

Dan, I don't think that "silver willow" is going to give any kind of willow effect. It looks like you are going to get some kind of silver, streamer type stars. I would actually try adding the Ti to either TT or Willow charcoal stars and see where that gets you.

 

I think the actual metal plays a big role in whether or not it's going to get burnt up. If you add Mg, it's probably never gonna be seen unless it's big chunks. MgAl, even 200mesh will not really leave much a tail. But with Al or Ti, it seems to take more heat and time for the particles to light up, allowing firedust tails to be possible, even with finer meshes. The star really should be fuel heavy, like charcoal stars, for the effect you are trying to get. The charcoal tail is half of the firedust effect, without it, you are not going to make much more than some kind of silver tailed star.

[dan999ification]

I saw the stars in a rocket, the willow or drooping will be achieved by breaking the shells gently and making the stars bigger than normal.

psyco: thanks I never considered the reactivity of the metal though its obvious to me now. so the mgal should be burnt up in the star due to its reactivity leaving the ti and al to be thrown off, my al is smaller than specified, so it looks like the ti will be needed to get a longer tail, a few small sample batches may be needed.

 

I will try the ti in this comp ,and variations of crys of mystery and willow diadem. does anyone know a comp that uses lots of fine ti for firedust or glitter?

 

 

dan.

Edited October 5, 2013 by dan999ification

[FlaMtnBkr]

How much of your ti is very fine? If there is a lot of coarse it will probably work OK but you might be "losing" the fine stuff that burns up in the star. You could try getting a fine kitchen sieve and screening out the fine stuff. If it clogs up the screen it won't be a big loss.

 

I had an idea a while back after getting some of Skylighter's titanium dihydride and a couple weeks later got an email from them suggesting it. And that is to take the fines and use a binder and water and screening it to make larger clumps. They suggested trying 3 percent SGRS or gum arabic. I bet dextrin liquor would work as well. And any bigger pieces that you don't want can probably be crushed with a hammer and used or reprocessed. I haven't tried this yet but it's worth a shot.

Edited October 6, 2013 by FlaMtnBkr

[dan999ification]

what a wonderful idea, I see it working aswell. I have read around quite a bit on ti this fine and have mainly found that it has no uses in pyro trouble is it came from a pyro supplier I thought I was getting the 100# that I ordered not the 0-100# it is labelled as, other products have similar stories- different labels to the products you order. I know that by products are our materials.

 

there is very little 100# visible I'd say a few percent at most, it is mainly very fine dust that coats your finger, its impossible for me to say without screens but very different from the sponge I've had previously. It falls through every domestic screen ive seen, when added to a charcoal comp it disappears completely with 10% added, it hides in pinball prime nicely aswell, turns reports white with no sparks visible [ that's obvious ]

 

I have a few test stars to help judge how it will behave in differing fuel ratios and temps, the pita is not only using it up but i know that when I find this magic tailed star i want... i wont find the ti again

 

dan.

[Mumbles]

Dan, are you confusing mesh with micron? You keep saying you have 0-100 mesh Ti, but then refer to it as a powder and very fine. 0-100 mesh should be relatively coarse and be very suitable for long tails. Basically all particles should be visible by the naked eye. 0-100 micron would be relatively fine, and generally useless for tails.

 

I'm not sure where you got the formula from, but it doesn't look like it'd give a tail length I'd equate to a willow. Maybe the .1mm Al is important. For a real willow type star I'd expect to see much less oxidizer. I have no doubts that it will make an okay silver tailed star as is though. Adding other auxiliary fuels, like red gum, will help to extend the tail length.

[dan999ification]

thanks mum, I can see most of it but then I can see 200# mgal with no problems. it is fine, ill check the mesh to micron chart.

 

so if I add red gum to the comp I have it will help extend the tail length, is this because the red gum will be burnt allowing the metal to be thrown off?

will taking some perc out also help the ti to be thrown off?

how about this:

kclo4 45

Ti 24

al 10

red gum 9

sulphur 3

charcoal 5

dextrin 5

 

I expect the burn rate to be slower due to the red gum, absence of the mgal and lower perc. am I on the right track? obviously i'll test and tweak until im happy.

 

Dan.

Edited October 14, 2013 by dan999ification

[Pyroboy]

Jep, the additional organic fuel leads to a lack of oxygen for the metal so it can seperate from the star and be burned with the oxygen in the atmosphere.

 

I would try that comp with mixed Al and no Ti. Or just with additional Ti. If it is as fine as you said I think it will not give a long tailed star.

 

I use 4% Ti (< 100µm) in shimizus willow comp as brocate stars. For me that gives a nice effect and due to the fine titanium the comp can be rolled. You could try this with your Ti.