Pretty green flame Posted September 18, 2006 Share Posted September 18, 2006 Greets Wel my problem is that my stars do not give the desired effect. I mix up a batch of shimizus fountain formula (BP + 20% Al), this works very well as a powder giving off a lot of white spark but as soon as i turn them into stars things start to go wrong. The stars take fire very easily but instead of throwing out white spark it just burns with and orange light and leaves behind a glowing pile of crap, upon closer inspection it was revealed that the aluminium doesn't even burn. What could be wrong? Could the reason be too much water when i am pumping them (I used gum arabic solution for wetting them), crappy aluminium or what? The same happened to my other comps containing aluminium, as a powder it burns beautifully but when i turn them into stars they just get all crappy like. Thanks Link to comment Share on other sites More sharing options...
Mardec Posted September 18, 2006 Share Posted September 18, 2006 I have had the exact same problem Mill you bp first, that helps Coat the stars so they burn hotter (bp wil do) Do you put some H3BO3 in them? Al could be oxidised. & btw, if you make those stars big (if they only burn orange, you do get some cool effect). This is what happened with me: I shot the starIt got to break altitudeBam, louzy orange balls..Kept burning orange And al of the sudden they exploded with hell lots of fire light and burning al My gues is that they burned to cool and then reached critical temperature and it just worked as a flash powder inside.. Conclusion, your stars burn to cool for the al to burn, coat them with bp (+ 5% al for hotter fire). And if that didn't help your al might bad for this kind of stars And that would suck Link to comment Share on other sites More sharing options...
fredjr Posted September 18, 2006 Share Posted September 18, 2006 and leaves behind a glowing pile of crapDoes this mean you are just burning the star on the ground? A static test on the ground doesn't show you true performance of a star. My glitter stars look like that when burned on the ground but when moving though the air they throw off globs of molten material and make excellent glitter. What do they look like when shot from a stargun? Link to comment Share on other sites More sharing options...
Pretty green flame Posted September 18, 2006 Author Share Posted September 18, 2006 and leaves behind a glowing pile of crapDoes this mean you are just burning the star on the ground? A static test on the ground doesn't show you true performance of a star. My glitter stars look like that when burned on the ground but when moving though the air they throw off globs of molten material and make excellent glitter. What do they look like when shot from a stargun? I see, i will shoot one from a star gun later today and see it if works. Link to comment Share on other sites More sharing options...
Mumbles Posted September 18, 2006 Share Posted September 18, 2006 You may also want to try different formulas. Perhaps 10%. Some gerb compositions need the pressure and lack of atmospheric air to function properly. There is a thread in the composition section entitled "Meal and metal" or "metal and meal" that will fit your purposes here. Also another one is the "reeper silver" I don't remember if we still have that one, but it was meal with 10 or 15% -325 mesh atomised Al. Link to comment Share on other sites More sharing options...
Mephistos Minion Posted September 19, 2006 Share Posted September 19, 2006 Reeper silver looks gold on the ground, but as soon as it comes flying from a starmine at high speed it is a really nice bright comp. Definetly do a stargun test on them, or a starmine one if you have lots Also your gum arabic may be a problem. I think I remember draco aster having some troubles with TT stars bound with GA. Apparently the burn was way too slow/not at all. Perhaps they are not burning fast/hot enough to light the Al propperly. Perhaps use dextrine next batch, that is if they fail the stargun tests. Link to comment Share on other sites More sharing options...
Pretty green flame Posted September 20, 2006 Author Share Posted September 20, 2006 I have done a star gun test and although it was better it did not produce many white sparks. Could it be that i am not produceing a hot enough flame so the Al doesn't burn? Link to comment Share on other sites More sharing options...
Draco_Aster Posted September 20, 2006 Share Posted September 20, 2006 Yah, gum arabic is OK aslong as you change the comp to suite as it is a fuel. Totally wrecks good BP and rich fuel comps. Link to comment Share on other sites More sharing options...
al93535 Posted September 20, 2006 Share Posted September 20, 2006 Pretty Green Flame: You nailed it. Especially with larger meshes of al you need a hotter oxidizer! I had this problem. You can easily fix it though! Add a bit of perc, or barium nitrate! Also, it helps to use a small % of fine aluminum to get the comp burning really hot. Link to comment Share on other sites More sharing options...
Pretty green flame Posted September 20, 2006 Author Share Posted September 20, 2006 Cheers! I will try some Ba-nitrate as i have plenty of it .Thanks for that Al Link to comment Share on other sites More sharing options...
Pretty green flame Posted September 22, 2006 Author Share Posted September 22, 2006 Al, i'd like to thank you for the tip (about the Ba-nitrate), my stars are working as they should. Thanks again. Link to comment Share on other sites More sharing options...
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