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Electric green strobe


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#21 Mumbles

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Posted 16 February 2011 - 04:08 PM

That probably came from Wouter Visser's database initially, or at least a bad copy and paste of it. That ingredient is nothing, just an artifact of the next formula present in the list, which is "Twinkling Red Star". The class part may have come from an html error. The correct formula is below, and referenced from page 225 of FAST.

Barium Nitrate - 40
Mg (linseeed oil coated) - 18
Sulfur - 30
Antimony Trisulfide - 7
Hexachlorobenzene - 5

Bound with 25 parts of 10% nitrocellulose lacquer. A mesh size is not given in the original source, but quite often cited as 60 mesh in the various repostings online.
Just so you guys quit asking, here is the link to the old forum. http://www.xsorbit2....forum/index.cgi

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#22 shagaKahn

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Posted 16 February 2011 - 07:40 PM

Mumz, you are the man. Thanx a meg.

(One day I'll have a video decent enough to show the effects of all y'all's help with this topic).

Best,
s

#23 shagaKahn

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Posted 20 February 2011 - 03:28 AM

"Schizo-Strobe."

Don't know what else to call it, my impatient variation on Shimizu's theme of Green Twinkling Star #2, loaded into a strobe pot:

http://tinyurl.com/5wdd8ju

(There's a fullscreen toggle on the right side of the play bar).

#24 shagaKahn

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Posted 22 February 2011 - 02:30 AM

Got a batch of -60 mesh Mg/Al and tried again to replicate V's electric green strobe.

You'll see from this video, somehow I still ain't quite there yet:

http://tinyurl.com/4r52lsd

The -100 mesh actually comes closer to strobing than the coarser mesh.

How long to you let your strobes dry, V?

#25 Voryon

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Posted 22 February 2011 - 03:22 PM

Got a batch of -60 mesh Mg/Al and tried again to replicate V's electric green strobe.

You'll see from this video, somehow I still ain't quite there yet:

http://tinyurl.com/4r52lsd

The -100 mesh actually comes closer to strobing than the coarser mesh.

How long to you let your strobes dry, V?


Hmmm now I think its going to become a little more laborious...

7 days should be more than enough to have fully dried stars, I normally dry mine for at least 7 days before priming (water based) but strobing wasn`t a problem after drying them overnight (always doing a test before priming).

When I would encounter your problem, the first thing I would do is to weigh the chemicals on another scale and/or try to get a known weight (sometimes coins have a specified weight or I´ve been using Airsoft BBs) on my scale to test that it is working correctly (even if it is unlikely that this is the problem, because most scales show a relativ mistake and so it would be more or less constant on all the chemicals but who knows, this is at least something that can be easily sorted out).

What kind of NC are you using? I would assume that ping-pong NC contains too much impurities that could add too much fuel causing constant burn, I use plain NC (the one used for stage-pyro dissolved in acetone).

If your NC is ok and your scale has proofed to be working properly, I would start to play a little on the ratios of the chemicals. As it seems that your composition burns too violent I would do the following:

1. Double the Barium carbonate content -> test batch #1 (assuming you have a 0,01g Scale you can do that in batches of 1/10th of the given ratios)
2. Use 12 parts of parlon instead of 7 -> test batch #2
3. Leave out the potassium nitrate -> #3
4. Use 19 parts Magnalium instead of 24 -> ...
5. Double the amount of CuO and CuCl
.
.
.

watch the results of these test batches and write down some notes (videos are best), ask yourself if something inbetween those changes might lead you in the right direction.

Hope that helps a little,

Voryon

Edited by Voryon, 22 February 2011 - 03:28 PM.


#26 shagaKahn

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Posted 22 February 2011 - 09:58 PM

Hey V that's great advice to calibrate my scale. We had a digital bath scale and 'cause it was so spiffy with its huge LCD display we just assumed it was accurate--and with its trademark "150 years of accuracy." Turned out to be off by 5% and it could NOT be re-calibrated.

As for my NC lacquer, I brew my own with gun cotton and acetone.

Will try tweaking component ratios and see if that makes a difference.

Thanx Voryon for your thoughtful advice. Yours is truly a gorgeous strobe and I'm determined to get it.

Oh and just as an aside, finally sprang for a good respirator. (Not wanting to replicate Mumbles barium poisoning).

#27 Voryon

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Posted 23 February 2011 - 03:23 PM

I really don`t know what a digital bath scale is, but I would think that this is the thing I use for weighing my body which means it is capable of measuring XXX.X kg, which would be nowhere near practical for normal amateur pyro scale as I don`t think your making compositions by the tonne????

Apart from that (as I don`t think you are using a XXX.X kg scale), a scale that`s not capable of being calibrated (or better not adjustable) doesn`t seem to be trustworthy to me either...the fact that it is off by 5% strenghtens this belief, as weighing should be one of the most accurate methods we know. Just to say I do have quite some experience in this field, as a good part of my job is quality management in an analytical laboratory, we consider the last digit of a scale as uncertain which would be somewhere between 0,01 and 0,05% with a good lab scale and maybe 5-20 times worse with el cheapo scales (assuming we are weighing somewhere not too near the lower end of the operating range). I never ever had a problem with a pyro-composition being made considerung the rule of not trusting the last digit of my scale even with my cheap 200g/0,01g (20€) scale which would mean not weighing any single component with less than 0,1g.

I do stress that point because this composition is a little "pyro-unusual" having single components that just contribute ~ 0.9 % which makes it necessary to have quite a low operating range when not making test composition by the kilo, which doesn’t matter when making 75-15-10…

#28 shagaKahn

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Posted 23 February 2011 - 06:30 PM

My fault for referencing "bath scale." It's the kind that usually goes in the bathroom and yes it's for weighing humans, not pyro.

Do have quite a collection of cheapish digital scales accurate (supposedly) to 1/10th gram.

It's with all these different scales together that I can compare a given weight and see if they all agree. (So far they do).

More I study and try to produce strobe pots the more I appreciate the subtlety of this particular effect.

Wondering if the "more traditional" strobes made with AP and straight Mg are easier and more dependable than those made with Mg/Al.

Thanx as ever V--and I'll keep you posted.

#29 shagaKahn

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Posted 25 February 2011 - 11:35 PM

As I wait for still another try at this electric green to dry I'm wondering if anyone else has experimented with this comp?

For strobes?

Meantime, speak of more "conventional" strobes made with AP, here's a variation on my own Schizo-Strobe theme with a tighter strobe interval than that previous psycho model:

http://tinyurl.com/6gmzrvc

Again there's a fullscreen tab on the right side of the play bar.

Though this one does have Barium salts, even with the camera stopped down to F11 I can detect no green in the flash. Gotta say I love the sound it makes.

#30 shagaKahn

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Posted 03 March 2011 - 11:39 AM

OK, here's a vid with two more variations of your formula. You'll see there ain't much difference in the behavior of the two comps and there's still nothing even approximating a strobe effect:

http://tinyurl.com/4wekbs7

May have to bag this experiment for a while.

#31 redtoolpusher

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Posted 26 December 2011 - 01:09 PM

Be care full there, nitro guanidine is an oxygen generator in this formula , so you might get a a none flikering effect,
find it or

See the thread here:
http://www.amateurpy...ple-strobe-pot/

Leave out the Strontium and it makes an extremely vivid blue strobe.

I've tried a few guanidine Nitrate strobes but never got anything particularly great, hence trying to formulate my own. The silicone blue strobe rocket fuel can apparently be made to strobe in a pot but I never managed it.



#32 Mumbles

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Posted 26 December 2011 - 06:12 PM

Guanidine nitrate is not the same thing as nitroguanidine. Also, being an oxygen generator is how this formula works. It does make up part of the oxidizer content.
Just so you guys quit asking, here is the link to the old forum. http://www.xsorbit2....forum/index.cgi

The sky is my canvas, and I have 2,113 pounds of powdered paint in the workshop.

#33 rveline

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Posted 18 November 2012 - 06:50 AM

a green strobe
ammonium perchlorate 60
barium sulfate 12
barium carbonate 8
magnalium -200mesh 16
parlon(chlorinated rubber) 4

bind with NC laquer
this just works, you can add more MGAL and lower ammonium percclorate to increase strobe frequency.




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