273 replies to this topic

[MMMMMM Pyro]

pyromaniac303
As far as i know the Al is not coated,it's 99% pure and from hobbychem.it came monday in a sealed back and i transferred it straight into a airtight container and it's stored in a cool dry place.The pile i lit was about 0.5g and took around a second to burn,so it wasn't that fast.

MMMMMM Pyro
I did test it in a 100mm 12mmID unchoked tube (hand pressed) earlier this week and got the same results.This is my reason for my test tonight.

thanx for the replies guys

regards
dean

Is there any chance of a vid?
This is really wierd, my 300mesh Al is from Hobbychem and works fine in fountains.
Perhaps, unlickly though it may be, the spray and intensity from the Charcoal is overpowering the Al sparks.
If you are able to, try a different comp perhaps:
KNO3 5
Ba(NO3)2 45
Al 45
B.P. 5
This has always yielded good results for me, and if this works that eliminates the Al as a variable...

Regards,

Mike

[portfire]

Is there any chance of a vid?
This is really wierd, my 300mesh Al is from Hobbychem and works fine in fountains.
Perhaps, unlickly though it may be, the spray and intensity from the Charcoal is overpowering the Al sparks.
If you are able to, try a different comp perhaps:
KNO3 5
Ba(NO3)2 45
Al 45
B.P. 5
This has always yielded good results for me, and if this works that eliminates the Al as a variable...

Regards,

Mike

Im going to do some more test tomorrow so will video them (i'm starting to realise the importance of videoing my test )

I'v only just started to build on my chemical collection so lacking on the Ba(NO3)2.(it's amazing how many effects you can achive with kno3/c/s )
I may try a slower meal aswel . as you say it may be the spray and intensity from the charcoal.

regards
dean

[Pyromaster2003]

Try milling the green mix for 3 hours instead of one and it should work well.

[portfire]

Try milling the green mix for 3 hours instead of one and it should work well.

I do have some 3 hour milled BP (10/15g). The only thing thats different than just milling the three chems is that the charcoal was milled for 10hr then milled with sulphur for 5hr and then 3hr with kno3 (it's really fast, i granulate it and use it for my star guns),would this effect the result? I will mill a green mix for 3hr tomorrow though and try again.


regards
dean

Edited by portfire, 01 March 2007 - 10:07 PM.

[portfire]

Hi all
At last success.
http://video.google....622710824950902

It was only a small test in a 60mm 11mmID unchoked tube.Thanx Pyromaster2003, the 3hr milled greenmix did work,so it was my BP that wasn't burning hot enuff


regards
dean

[Zinginex]

Every composition should be treated with respect, but you're right - adding metal powders (especially Titanium) increases the sensetivity of the composition. Any BP-type composition with added metal should be pressed, not rammed. In practise you can get away with ramming some metals, and hand-pressing if you don't own a press, but that's not to say an accident will never happen. I would advise airing on the side of caution - if in doubt, press, and press behind a blast shield.

Ok thanks v. much

[Pyromaster2003]

Glad you got it sorted mate now for one with a choke - should be 2/3 times higher than the un-choked one in the vid!

[portfire]

Yeah i'm making it's big brother tonight.100mm 15mmID with 5mm choke.i'll post the vid




regards
dean

[BrightStar]

I tried a red Fe-Ti fountain over the weekend. The formula was based on John Glasswick's:

Red gum - 8
Parlon - 18
Magnalium (200 mesh) - 18
Fe-Ti (mixed 20 to 100 mesh) - 13
Strontium nitrate - 43

The strontium nitrate was oven dried at 200C for an hour before use. 20g of comp was dampened very slightly with thin NC laquer, and hand pressed into a strong 1/2" by 5" tube with 3mm walls. The clay choke was 6mm diameter and the depth of composition was about 3.5".

The result is here (divx, 4,464 KB)

It started well with excellent colour and a good plume of sparks (probably due to the short core made for ignition) but was a bit weak thereafter. The tube burnt through after 30s or so. A shorter version is called for, perhaps with a longer core...

EDIT 04/07: On testing a second fountain with the same forumula, it took 4 attempts to ignite with visco. You may need to devise some sort of priming method for reliable first time ignition.

Edited by BrightStar, 20 April 2007 - 12:16 PM.

[Zinginex]

Quick questions. My aluminium just arrived and its 300 mesh. Is this too fine for use in fountain if i mix it with very slow burning bp? Could it become a very fast burning comp? Whats the best mesh for metal powders in fountains? Thanks

[portfire]

Hi Zinginex
300 mesh Al is fine for fountains (it's what i'm using at the moment). From personal experience you need a hot burning BP.The first couple of times i tried it was with 1hr milled BP and all i got was yellow/orange sparks,so after advice from Pyromaster2003 (thanx again) which was to mill greenmix for 3hr,i finally got white sparks.

To answer your question 'Could it become a very fast burning comp'. My 3hr milled greenmix was quite fast (went with a nice whooosss) and after adding the Al did slow down a little,so i think you should be ok.




reagrds
dean

[Zinginex]

Hi Zinginex
300 mesh Al is fine for fountains (it's what i'm using at the moment). From personal experience you need a hot burning BP.The first couple of times i tried it was with 1hr milled BP and all i got was yellow/orange sparks,so after advice from Pyromaster2003 (thanx again) which was to mill greenmix for 3hr,i finally got white sparks.

To answer your question 'Could it become a very fast burning comp'. My 3hr milled greenmix was quite fast (went with a nice whooosss) and after adding the Al did slow down a little,so i think you should be ok.
reagrds
dean

Ah thank you very much dean. I just made 2 fountains with about 30/70 of Al and i think it was balsa charcoal i used for the bp. It was little sticks from a helicopter making kit . It was pretty slow bp as it was only mortar and pestled for a bit but the fountains were excellent. One choke was cat litter and the other was polyfilla. After a lot of attempts at fountain making i found that cat litter and pollyfilla make excellent chokes

[koobee]

So I have been working on getting... "professional"... appearance to my fountains. I have been using parlon stars in a bp based fountain and have had decent results, they kinda look... unintelligent. You know, the kind of fountain that really functions, but seems just kinda... bad. I know I am doing a terrible job of explaining. The stars light, but I want to know how big to make the stars and how much I should put in the bp composition to give the fountain a full effect. Any small formulas for stars, or meathods would help, and if this is already a thouroughly discussed topic please refer me to the proper article and I will remove the post.
Thanks all!

[YT2095]

One choke was cat litter and the other was polyfilla. After a lot of attempts at fountain making i found that cat litter and pollyfilla make excellent chokes

ROFLOL, I`ve just been through every single page in this thread and it happens that the second but last post mentions Polyfiller, that`s exactly what I use also, although I`m probably a little out of my depth here with some of the demos and techniques used by the more experienced compared to my humble Fountains.

I prime the rim of the tube with a smear of of polyfiller 1`st pressing it in hard, that gives the rest a good purchace and rought surface to adhere to later, then I tear a rizla paper in half, and add the polyfiller into the tube that`s resting on the paper, this is all resting on a small peice of wood, and with a few sharp taps you can knock the air out and get a nice level plug.
after a couple of days I then drill these out, and then counter sink the hole on each side a little to allow a better gas flow.

then I plug the hole with cotton wool, and load in the pyro comps, in a First in/First out order, so for traffic lights it would be Strontium, Sodium and Barium for the red yellow green.
it`s hand pressed gently at each stage, and the end I put a sheet of paper that just fits the ID of the tube and seal it with NC laquer, then I apply a second coat of NC when that`s dry.
then I seal the end off with polyfiller again and wait another few days.

take the cotton wool out, make an ______\ with the visco, pop that into choke hole and put the cotton back.

it`s only simple I know, but it works well for me

[portfire]

I think you could save time by making some (really easy) fountain tooling as they form the choke/nozzle in one go,then press your comp and remove the tube from the tooling and your ready to go.Once you've got the tooling you nock them out pretty quick.I'll post a pic of mine later just to show how easy they are.


dean

Edited by portfire, 12 July 2007 - 08:10 AM.