55 replies to this topic

[sizzle]

So I should use 15:3:2 and make it into granules then?

[Frozentech]

I'm having trouble with my Roman Candle Lift Powder at the moment, I'm trying 6:3:1 powder which has been made with the CIA method and passed through a sieve to a grainy powder. I've tried exactly how has been shown on Dan William's page but the stars barely go 3 inches out of the tube before they hit the ground. What can I do? I need to make some Candles for Christmas Eve.

That ratio is closer to the delay comp that you want between shots. Use a decent hot 75:15:10 as you would for lift charge for shells, and try the delay comp listed on Dan's page between stars. if the star size is right and the lift is right, they will definitely *whoomp* out of the tube. Hehe... now I have the urge... you gave the inspiration of what to make today. I was going to press powder and corn it, but thats too much like work.

[paul]

Second that! Had great success with 2hrs milled bp which was wettened with water and then riced through a sieve to stop it from dusting around. Adds a bit speed, too!

This stuff even worked for 20mm roman candles with 15mm cut stars in it! You don?t even have to add much of it.

with best regards,

paul

[The_Djinn]

apart from your lift comp, are the stars a snug fit ? otherwise the lift gass could be escaping passed the sides of the star rather than lifting it hence your not getting much height.

Mark

[sizzle]

as far as I understood (and as Dan Williams guide shows) the stars should have about a 2mm gap each side, mine do. I used a 1/2" tube (like Dan) and 3/8" Stars (also like Dan).

I am just making some 15:3:2 black powder as we speak, it should be dry by Saturday night so I'll try it then and give you all an update.

Edited by sizzle, 17 November 2005 - 08:23 PM.

[JamesH]

A 2mm gap either side seems rather a lot for a candle that size, thats 4mm total difference between tube I.D. and star diameter. You need about half that. That might be contributing to your lack of height.

Edited by JamesH, 17 November 2005 - 11:25 PM.

[sizzle]

Well, if the 15:3:2 powder doesn't improve it too well i'll make some bigger stars. Thanks for the advice.

[completebeginner]

i found that the best proportions for bp to be 70 20 10 kno3 c s made with alder charcoal

[The_Djinn]

2mm each side is to large a gap. 2mm or a little less total would be better. Another thing is if your stars are cylinderical, they should be roughly 1 and a half times your tube ID in length so they do not jam up in the tube which would cause it to burst... not an issue with round stars though.
4mm space on a candle that size would definately contribute to lift problems as the gass would pass by the star very easily.

I would guess you have a load of stars made up... 2 choices here... roll them around in more compound to build up there diametre or if they are cylinderical then as a test you can wrap a layer or 2 of craft paper around them to fatten them up... will soon prove if the lift is the issue or the star diametre.

Mark

[Frozentech]

2mm each side is to large a gap. 2mm or a little less total would be better. Another thing is if your stars are cylinderical, they should be roughly 1 and a half times your tube ID in length so they do not jam up in the tube which would cause it to burst... not an issue with round stars though.
4mm space on a candle that size would definately contribute to lift problems as the gass would pass by the star very easily.

I would guess you have a load of stars made up... 2 choices here... roll them around in more compound to build up there diametre or if they are cylinderical then as a test you can wrap a layer or 2 of craft paper around them to fatten them up... will soon prove if the lift is the issue or the star diametre.

Mark

Speaking of Roman Candle stars, I just tried out a pump from Wolter, for some 17.5 mm stars to shoot in 3/4" ( ~19mm ) candles. Once they dry I need to do some lift tests ( I want to equalize the lift height for all the stars ) I plan to use 18" (45cm ) for the overall candle length. I'll make sure to get pics of the lift tests and finished candles.

Here are the pumped stars :

//http://www.mtaonline.net/~mbowers/candlestars.JPG

Has anyone had experience with these type stars with the central hole through them ? How about priming ? I am planning to just fill the passfire with pulverone. I am hoping that no prime will even be required since they should take fire from the center and outside. These will be the largest candles I have made yet and I am a trifle shaky on how they scale up, you know ?

Sigh... I hate waiting for things to dry.

Edited by Frozentech, 18 November 2005 - 10:59 PM.

[paul]

I think filling the holes with pulverone is one idea but a better one would be to stick a piece or two of blackmatch in the holes and fasten them there with a bit of bp/nc laquer or something.

This comes to my mind as I have used this for such pumped stars, too and it ignited the whole star at once.

[The_Djinn]

main reason for the hole in the middle is so that you can use black match to pass fire through the centre of the star to the lift charge beneath... igniting the start at the same time.

Mark

[sizzle]

Well, I tried 15:3:2 with one of my largest stars (about 1.5mm gap in total) and it still only reached about 4 inches out of the tube. Is my Black Powder not of high enough quality? I use GD's KNO3 and S, and for C I use thegreenman.me.uk's stuff. To make it I mix them all together in a small amount of boiling water and then let the water evaporate and crush the clumps through a sieve, I also tried using it for my Film Canister salute but that barely got 4 inches out of the tube too. I tried KP burst for the Canister salute and it seems to work, can this be used in Candles too?

[fishy1]

use a ball mill or the CIA method for lift.

[Frozentech]

Well, I tried 15:3:2 with one of my largest stars (about 1.5mm gap in total) and it still only reached about 4 inches out of the tube. Is my Black Powder not of high enough quality? I use GD's KNO3 and S, and for C I use thegreenman.me.uk's stuff. To make it I mix them all together in a small amount of boiling water and then let the water evaporate and crush the clumps through a sieve, I also tried using it for my Film Canister salute but that barely got 4 inches out of the tube too. I tried KP burst for the Canister salute and it seems to work, can this be used in Candles too?

Well, you need to work on the BP. The way you made that didn't cool the solution fast enough to force the KNO3 to rapidly precipitate into *very* small crystals. Try following the CIA method directions more exactly and you'll see what I mean.

I tried out one of those stars I posted about today, using a short 3/4" tube ( trying to dial in the lift for the first few stars ) I used 4 gm of ball milled pulverone. It went up about 25 feet ( I know I can get better though) and the good news, the red pumped star worked perfectly, even in daylight it was brilliant red, like a signal flare, and extinguished before it hit the ground. I fiddled with the Davis delay comp by using 36 mesh charcoal and adding 4 gm of granular ferro-titanium and it makes the delay nice and sparky. I might just go waste a blue and a green star and test my 'mid tube' lift charge ( trying to make 18" long 3/4" candles and want the stars to all reach the same heights ) before hitting the sack tonight.

You candle masters out there... what ratio of lift charge weights do you use for the first star, mid level stars, and the bottom stars ? Do you bother with trying to 'calibrate' the lifts to the tube length ?