What are your opinions on crackle?

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richardh08
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What are your opinions on crackle?

Post by richardh08 »

As people may be aware, Ken and I have been running a long series of trials of a wide variety of crackle (and potential crackle) compositions. Some general features are starting to appear from our results that seem to suggest that the mechanism might differ from what I believe to be the general view of how crackle works. But it occurs to me that my understanding of that view might well be out of date, so I would appreciate hearing other people’s thoughts on the topic.

As a starting point, I note that virtually every composition we have come across contains some or all of the following ingredients:

1. A medium to fine grade of magnesium-aluminum alloy (usually 50-50)
2. A fine grade of atomized aluminum
3. Copper oxide
4. A heavy metal (usually lead or bismuth) oxide
5. Nitrocellulose (or double-base powder)

The occasional formula includes one or more of a few other substances, but I’m making the assumption that such materials are not crucial to the basic mechanism. The most popular crackle – and, quite frankly, probably by far the best performing one that I have come across – appears to be the one described by Lloyd Sponenburgh, which contains everything in the above list.

But, regardless of a composition’s performance, I’d like to hear your views on the relative importance of any or all of these substances; are they essential or could they, in some formulations, be omitted? Also, if you have any thoughts about the likely function of any of these materials in the creation of the crackle effect, I would appreciate hearing your opinions.
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Lloyd
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Re: What are your opinions on crackle?

Post by Lloyd »

Oh, Man! You're going to make us think again? I'm all 'thought out' try to resolve some chemical sourcing problems.

Sigh... I'll think. But opinions won't come until I'm not thinking about it. That's the way it always happens.

<grin>
Lloyd
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richardh08
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Re: What are your opinions on crackle?

Post by richardh08 »

It wasn't my intention to force people to have to think hard about these questions.

I simply want to know what opinions people currently have and, in particular, whether any of those opinions have changed since Shimizu put forward his ideas on the mechanism, in 1990. After all, that was over 25 years ago and there are formulations now in existence that he could not have known about at the time.

If anyone has thought - or wants to think - about it, so much the better; but it isn't a requirement.
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Lloyd
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Re: What are your opinions on crackle?

Post by Lloyd »

Richard,
Sometimes "wry" humor doesn't come across well.

I have little time to do physical research, but I think about this problem all the time, because crackle is one of those effects "close to my heart".

One part of the 'think' algorithm is that I must go back and re-read your findings. I was remiss in not creating a summary of what you did, as you did it.

Lloyd
"Pyro for Fun and Profit for More Than Sixty Years"
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richardh08
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Re: What are your opinions on crackle?

Post by richardh08 »

And I tend to be excessively worried about the possibility that I might have annoyed or upset someone (except, of course, when I deliberately aim to do it <grin>).

I think I know what your opinions are, Lloyd - at least, I think I know what they were before we started our somewhat vigorous discussions! Of course I value your input, but I'm hoping to get responses from anyone who hasn't followed what Ken and I have been doing.
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Boophoenix
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Re: What are your opinions on crackle?

Post by Boophoenix »

I'm a bit ashamed to admit I'm not a huge fan of crackle. Which is sad being surounded by such gifted minds who are fascinated by it. I must admit though following along and doing some testing myself it has gotten a little more interesting.

Now that the days are getting longer I hope I can get a chance to dig back into some trials of it and some other projects.

This could become a pretty facinating thread.
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