Crackle mix/dragon eggs

All Recipes and Chemistry!

Moderators: richardh08, Boophoenix, Lloyd

Colour_the_sky
Posts: 59
Joined: Tue Sep 11, 2018 10:39 am

Re: Crackle mix/dragon eggs

Post by Colour_the_sky »

Very nice ! I also would like to try them. Is there any recommended mesh size for the MgAl ? I have 325-400 mesh and 150-200 mesh MgAl.

I could try both too but I wanted to hear If there is some experience because the most mesh size I have seen is 200-250 in crackle compositions.


Colour_the_sky
User avatar
Lloyd
Posts: 1902
Joined: Sun Aug 09, 2015 1:43 am

Re: Crackle mix/dragon eggs

Post by Lloyd »

I use -200 mesh MgAl and 12u atomized aluminum.

Lloyd
"Pyro for Fun and Profit for More Than Sixty Years"
User avatar
richardh08
Site Admin
Posts: 2226
Joined: Wed Aug 07, 2013 1:54 pm
Location: Bedfordshire

Re: Crackle mix/dragon eggs

Post by richardh08 »

If you aren't as concerned as Lloyd is about consistency of timing and performance, I've found that his crackle is quite forgiving of variations in particle size. I've had it work fairly well using -60 +100 mesh MgAl and -100 mesh atomized Al.

Ideally, the Al ought to be -350 mesh, but using -150 +200 mesh MgAl should be OK.
Even when I'm wrong, I'm convincing.
User avatar
Pyro-Gear
Site Admin
Posts: 3034
Joined: Wed Jul 10, 2013 8:24 am

Re: Crackle mix/dragon eggs

Post by Pyro-Gear »

It should be interesting to see how the MG/AL I smelted works 60 aluminium 40 magnesium even though I slightly over milled it.
Colour_the_sky
Posts: 59
Joined: Tue Sep 11, 2018 10:39 am

Re: Crackle mix/dragon eggs

Post by Colour_the_sky »

I have mixed my first batch it needs to dry. Can´t wait to test it ! :lol:
Thanks richard08 and Lloyd, so I took my 150-200mesh MgAl. I don´t have atomized Al right now but it should work without it too after what I have seen.

Colour_the_sky
User avatar
Lloyd
Posts: 1902
Joined: Sun Aug 09, 2015 1:43 am

Re: Crackle mix/dragon eggs

Post by Lloyd »

Colour,

You need the extra aluminum in there, even if it's not of the atomized variety, It is important to the loudness.

Lloyd
"Pyro for Fun and Profit for More Than Sixty Years"
User avatar
richardh08
Site Admin
Posts: 2226
Joined: Wed Aug 07, 2013 1:54 pm
Location: Bedfordshire

Re: Crackle mix/dragon eggs

Post by richardh08 »

I was going to say the same as Lloyd, but he beat me to it.

Something one of us should have asked earlier - which crackle composition are you using? I think we've all been assuming it's Lloyd's, but maybe it isn't.
Even when I'm wrong, I'm convincing.
Colour_the_sky
Posts: 59
Joined: Tue Sep 11, 2018 10:39 am

Re: Crackle mix/dragon eggs

Post by Colour_the_sky »

Oh sorry I forgot to mention it in my happyness ! :o
I tested one of the chinese style with only Cu2 based oxide.

I took it from one of their datasheets.

In parts:

50 CuO 325 mesh
20 MgAl -200 mesh
20 Ti 200 mesh sponge
10 Rice starch( though I used dextrin from corn starch)

If any then I have only flake Al. I can exchange it with atomized?
Would it make a difference to add Mg 200mesh or will it make worse ?
I have read that Al is the one which makes the bang in crackling as long I did understand takeo shimizu right but Mg could make it easier to ignite. Thought the Al which
is in the alloy could be enough but thanks for the advise given both of you ;)

I found bismuth trioxid too expensive, so I wanted to see how well this works.
Because I know the other one which also Lloyd is using ? Works brilliant I know.

Colour_the_sky
User avatar
richardh08
Site Admin
Posts: 2226
Joined: Wed Aug 07, 2013 1:54 pm
Location: Bedfordshire

Re: Crackle mix/dragon eggs

Post by richardh08 »

That's one I haven't tried, so I will be very interested to hear how it performs. I've seen a similar composition described as behaving half-way between crackle and a glitter. I suspect it won't produce loud reports, but it might look very good in the air.

In my experience, adding any type of elemental Mg will not help and will make the composition just burn and not crackle at all. I suspect that flake Al might be too reactive to give the right effect, but I don't know for certain. If it is a moderately coarse flake, it might work. Why not give it a try?
Even when I'm wrong, I'm convincing.
Colour_the_sky
Posts: 59
Joined: Tue Sep 11, 2018 10:39 am

Re: Crackle mix/dragon eggs

Post by Colour_the_sky »

I made some from aluminium foil and my kitchen sieve is about 10 and one about 20 mesh this won´t be too fine and reactive so you are right next time I try it.

They are pretty nice for cheap white flashing sparks in the air not so fast like Ti flying more slowly like charcoal I like the effect too.

How much should I add the magical 5% ?

I will make a starmine video as a matrix star
User avatar
richardh08
Site Admin
Posts: 2226
Joined: Wed Aug 07, 2013 1:54 pm
Location: Bedfordshire

Re: Crackle mix/dragon eggs

Post by richardh08 »

Colour_the_sky wrote:How much should I add the magical 5% ?
That might be a good amount to start with; many crackle compositions use MgAl and Al in an approximately 2:1 ratio, but there are no definite rules to follow.

A somewhat unusual composition was posted on FW a little while ago:

41 Bi2O3
40 CuO
03 MgAl
13 Al, atomized
03 Phenolic resin

It is fairly easy to ignite and appears to work very well, despite having very little MgAl.

It is somewhat reminiscent of the types of composition that I'm currently playing with, but my primary aim is to understand the mechanism rather than to find an effective formula. My mixtures tend to be more extreme and usually perform a lot less well. For example, the other day I tried a composition that had only about a 40% success rate in creating an explosion and had a delay of about 14 seconds. Nobody is going to use it in place of the more popular compositions, but it gave me another point to put on one of my graphs.
Even when I'm wrong, I'm convincing.
Colour_the_sky
Posts: 59
Joined: Tue Sep 11, 2018 10:39 am

Re: Crackle mix/dragon eggs

Post by Colour_the_sky »

Oh boy it was so perfect until I decided to use 20 per cent polystyrene as outer binder for my bp matrix mix. It was so hard to ignite and after ignition it took way too long to ignite the crackling balls but the camera did not pick it up because it was so low noise. :(
At least there was little crackling and some spark spitting Ti.

I used dextrin for the crackling balls so I don´t wanted to bind the bp matrix with dextrin too.
Polystyrene is not the easiest binder to work with. Any other suggestions ?

My bp works great without the polystyrene.

It´s :

60 KNO3
10 Sulfur
30 Charcoal beech( gives nice shower of sparks !)

I won´t give it up but I will show it when everything works fine. It´s a shame :(
Last year my golden powder lift worked so well after one year of time. It can´t lift anymore !
It was very lumpy in the plastic box. Moist?
User avatar
richardh08
Site Admin
Posts: 2226
Joined: Wed Aug 07, 2013 1:54 pm
Location: Bedfordshire

Re: Crackle mix/dragon eggs

Post by richardh08 »

Colour_the_sky, I don't know of anyone else who uses polystyrene as a binder, and 20% seems far too much.

If you need to use a non-water-based binder you could consider red gum (not very good), phenolic resin (better) or PVB (good, even in very small amounts). They are all activated by alcohol. Ken usually has them in stock, but it might be easier for you to obtain any of them from Fabian Werth at pyropowders.de.
Even when I'm wrong, I'm convincing.
Colour_the_sky
Posts: 59
Joined: Tue Sep 11, 2018 10:39 am

Re: Crackle mix/dragon eggs

Post by Colour_the_sky »

Yes 20% makes it nearly impossible to ignite. 10% worked but it seems to make a blob in the bowl and if your bp does not hit this blob your bp won´t hold together. It´s not easy to disperse in aceton.

Fabian Werth is a good source this is where I got my mgal from. The uk also was a good source to buy things hard to find like red 111 dye but after the brexit it´s not easy to source chems from uk because of customs control now. I hate it to drive 30km just to tell them what I want to do with it. Even things like electronic parts from china totally legal things.

Electronics is another of my hobbies and I also have colophony resin available if it works ?
I will get some of that PVB anyway to try it.
User avatar
richardh08
Site Admin
Posts: 2226
Joined: Wed Aug 07, 2013 1:54 pm
Location: Bedfordshire

Re: Crackle mix/dragon eggs

Post by richardh08 »

I'm sorry I've been a bit slow in replying but I've been a bit preoccupied with other stuff recently.

We haven't (yet) left the EU, so there ought not to be problems with customs control until we do. If there are problems now, then it looks as though somebody has 'jumped the gun'.

In the past I've experimented with a lot of different binders for crackle, including colophony resin. I've found that they all work to some extent, but that (apart from nitrocellulose and, perhaps, PVB) phenolic resin is the most effective foe me. That's why I now use it in all my trials.
Even when I'm wrong, I'm convincing.
Colour_the_sky
Posts: 59
Joined: Tue Sep 11, 2018 10:39 am

Re: Crackle mix/dragon eggs

Post by Colour_the_sky »

No worries I thought that you might be busy :)

No, I had no problems with the uk until now. The problems were only with reference to china because there is customs control. Not meant to be with uk too If you understood so.
I thought uk is already out of the EU because they said brexit is done and they didn´t talk about it in the news anymore. I just want to avoid buying when they are out and not because there are problems ;)

Do you know the date of exit then ? Maybe I could buy something in bulk before they really exit.

It´s just so funny some chemicals are cheaper in britan than in germany. Some you can find easier in uk even if they are not illegal nor regulated. One of these things is pvb as example :D But Fabian Werth has it luckily ! I got some to test.

Not mentioning nitrates, chlorates or perchlorates :lol:
Well ok the first one is just easy to get as a plain fertiliser.
Second and third are available via electrolysis but I stay with second.
Cheaper easier and not so dangerous as I always read. Avoid some
chems then you can work with it too.

Back to crackling again :lol:
It seems that dextrin also makes loud crackles but you need to heat it much more until it pops right ? This was my impression. I have looked over the whole datasheet and found my recipe in a table but this time as "time rain" and they calculated the bp and crackle mix together to 100%. I was thinking again what If they just mix both together and form little balls from that ? I wanted to give that a try. At least they would ignite much better. And yes time rain is not always the same formula !

the time rain I have chosen:

KNO3 25
S 8
c 10
CuO 30
MgAl 10
Ti 12
SGRS 5

If I look to other crackling mixes there is also:

CuO 60
MgAl 20
Ti 20

It seems that they just try to arrange the CuO+MgAl in some sort of ratio between
2 and 3.5 doesn´t matter If bp is calculated in or not.
User avatar
richardh08
Site Admin
Posts: 2226
Joined: Wed Aug 07, 2013 1:54 pm
Location: Bedfordshire

Re: Crackle mix/dragon eggs

Post by richardh08 »

If nothing changes between now and then, the UK will formally leave the EU on March 29, 2019.

I don't have much experience of making chlorates or perchlorates by electrolysis, so I can't really comment. Of the two, obviously, chlorates are simpler to make, but I'm not sure I would agree that the process is in any way 'less dangerous'. I don't want to enter the argument about the relative merits and hazards of their use in pyrotechnic compositions.

In my experiments, I've found several compositions that don't ignite properly when primed, no matter how 'hot' I make the prime, but will explode if subjected to an intense burst of heat from a blowtorch. It seems reasonable that crackle bound with dextrin - or with any binder other than nitrocellulose - is likely to need more heat to get it started.

In the past, I did try a few compositions that included BP ingredients and didn't have much success. But I didn't try very hard. I will be interested to hear how you get on with that time rain formula.

The stoichiometric ratio for the reaction between CuO and MgAl is very close to 4:1. The majority of crackle compositions that I've come across appear to have a slight to moderate excess of metal, so a ratio of 3.5:1 wouldn't be unreasonable.
Even when I'm wrong, I'm convincing.
Colour_the_sky
Posts: 59
Joined: Tue Sep 11, 2018 10:39 am

Re: Crackle mix/dragon eggs

Post by Colour_the_sky »

I will do a test tomorrow just waiting for the stars to dry but I did some test with the powder alone and came to conclusion 3.5:1 is the most agressive burn and it makes some quiet crackling noise when burned as powder espcially If you have sulfur in there ! If your MgAl is very fine(+325 mesh) and you heat it without a flame it makes a loud bang !

So I tried a mix with bp:

KNO3 60 30%
S 10 5%
C 30 15% (beech for nice golden sparks !)

and

CuO 70 35%
MgAl 20 10%
Dextrin 10 5%

I did 70 20 10 crackling bound on his own too. I will add it as small balls in a bp comet like above but bound with extra pvb 3%. The CuO 50 MgAl 20 Ti 20 crackle mix burns less energetic as open powder so I mixed more CuO in a hope that it pops more loud. I still can add in Ti later because I it has to work first.

Oh is there a platform for videos that don´t block videos like youtube?
I only know pyrobin but If somebody wants to suggest something be free !

EDIT : I have good news for you guys !

My tests with BP mixed in crackling was not what somebody expects but this is a strobe effect right ?

http://www.pyrobin.com/files/BpMixedDragonEgg.mp4

The dragon egg alone was a full win !

http://www.pyrobin.com/files/DragonEgg.mp4

This is another validation that crackling doesn´t need any bismuth nor NC laquer ;)

I wonder what aluminium will do If that was loud already!
Colour_the_sky
Posts: 59
Joined: Tue Sep 11, 2018 10:39 am

Re: Crackle mix/dragon eggs

Post by Colour_the_sky »

Sorry for the double post but I wanted that you can see my new post.

After my edit above here are even more new videos. I hope you all like it !

http://www.pyrobin.com/files/CrackleWithTi.mp4

http://www.pyrobin.com/files/CrackleWithTiMine.mp4

Colour_the_sky
Adr2412
Posts: 26
Joined: Mon Oct 29, 2018 3:40 pm

Re: Crackle mix/dragon eggs

Post by Adr2412 »

Something is wrong with the video. We are getting only the audio stream.

Regards

AZ.
User avatar
Pyro-Gear
Site Admin
Posts: 3034
Joined: Wed Jul 10, 2013 8:24 am

Re: Crackle mix/dragon eggs

Post by Pyro-Gear »

User avatar
Lloyd
Posts: 1902
Joined: Sun Aug 09, 2015 1:43 am

Re: Crackle mix/dragon eggs

Post by Lloyd »

Big, and LOUD! But, I think it's too slow from ignition to explosion for stars.

Lloyd
"Pyro for Fun and Profit for More Than Sixty Years"
Adr2412
Posts: 26
Joined: Mon Oct 29, 2018 3:40 pm

Re: Crackle mix/dragon eggs

Post by Adr2412 »

Yep this works so that is CuO , Magal and Dextrin ?
Colour_the_sky
Posts: 59
Joined: Tue Sep 11, 2018 10:39 am

Re: Crackle mix/dragon eggs

Post by Colour_the_sky »

Adr2412 wrote:Something is wrong with the video. We are getting only the audio stream.

Regards

AZ.
Only with firefox internet explorer opens that in windows media player or download it.
Lloyd wrote:Big, and LOUD! But, I think it's too slow from ignition to explosion for stars.

Lloyd
Maybe it needs more heat ?
Adr2412 wrote:
Yep this works so that is CuO , Magal and Dextrin ?
Yes make small balls and cover with prime or like in my mine as matrix star.
Thanks ! Yep is same by me ! My mobile phone cam doesn´t get the sound right outside.
But I still have the feeling adding 10% Ti lowers the explosion a bit.
User avatar
richardh08
Site Admin
Posts: 2226
Joined: Wed Aug 07, 2013 1:54 pm
Location: Bedfordshire

Re: Crackle mix/dragon eggs

Post by richardh08 »

Colour_the_sky wrote:This is another validation that crackling doesn´t need any bismuth nor NC laquer ;)
That's what I - and Ken - have been saying for quite some time!
Lloyd wrote:Big, and LOUD! But, I think it's too slow from ignition to explosion for stars.
Some crackle compositions make a loud and/or sharp report and others don't. Some have a long and/or variable delay and others don't. People will differ as to what they consider to be the important features.

My main interest is figuring out how it works. In that respect, any composition that produces a noise (and, sometimes, even when it doesn't!) is a useful addition to my dataset.
Even when I'm wrong, I'm convincing.
Colour_the_sky
Posts: 59
Joined: Tue Sep 11, 2018 10:39 am

Re: Crackle mix/dragon eggs

Post by Colour_the_sky »

My 70 20 10 mixture is less in delay than pyro gears in the video but maybe that depends how big you make the balls :lol:

I use 200 mesh MgAl and my balls are between 2-5mm.
User avatar
Pyro-Gear
Site Admin
Posts: 3034
Joined: Wed Jul 10, 2013 8:24 am

Re: Crackle mix/dragon eggs

Post by Pyro-Gear »

Dam you have small balls.
The test was using a very early composition, however shoot them through the sky and the reaction time reduces.
Colour_the_sky
Posts: 59
Joined: Tue Sep 11, 2018 10:39 am

Re: Crackle mix/dragon eggs

Post by Colour_the_sky »

Pyro-Gear wrote:Dam you have small balls.
The test was using a very early composition, however shoot them through the sky and the reaction time reduces.
I knew someone would catch my joke in between. :lol:
Cheers to you pyro gear :D

Could you alter the delay altering the CuO to MgAl reatio or is it just dependent on MgAl particle size ?
User avatar
richardh08
Site Admin
Posts: 2226
Joined: Wed Aug 07, 2013 1:54 pm
Location: Bedfordshire

Re: Crackle mix/dragon eggs

Post by richardh08 »

I don't know the answer to that question.

While it is true that some compositions have long delays and others have short ones, I don't know of any simple correspondence between the formulation and the delay. But that could simply be because I've never really looked for any such relationship. Whenever I've tweaked a composition it has been to try and improve the report and I didn't pay much attention to what effect the changes had on the delay.

I get the feeling that, for any given composition, tweaking the ratios doesn't have much of an effect on the delay, but I could easily be wrong.
Even when I'm wrong, I'm convincing.
Colour_the_sky
Posts: 59
Joined: Tue Sep 11, 2018 10:39 am

Re: Crackle mix/dragon eggs

Post by Colour_the_sky »

I want to replace the Ti in my composition with coarse Al glitter to see what that will do. Even just 10% Ti pushes the report down a bit. I need to look what I have laying around to mix it under the crackling to see what changes. I will write back soon Richard :D
User avatar
Lloyd
Posts: 1902
Joined: Sun Aug 09, 2015 1:43 am

Re: Crackle mix/dragon eggs

Post by Lloyd »

I believe you'll find the Al suppresses the report even more than the Ti does!

Lloyd
"Pyro for Fun and Profit for More Than Sixty Years"
Colour_the_sky
Posts: 59
Joined: Tue Sep 11, 2018 10:39 am

Re: Crackle mix/dragon eggs

Post by Colour_the_sky »

Lloyd could you explain why do you think that will happen ? I remember in the beginning you said Al is important for the crackling noise.
User avatar
Lloyd
Posts: 1902
Joined: Sun Aug 09, 2015 1:43 am

Re: Crackle mix/dragon eggs

Post by Lloyd »

Aluminium IS important to the crackling noise. But, in excess, it suppresses the burn rate and reduces the explosion, and the timing of the explosions is affected, also.

Lloyd
"Pyro for Fun and Profit for More Than Sixty Years"
Colour_the_sky
Posts: 59
Joined: Tue Sep 11, 2018 10:39 am

Re: Crackle mix/dragon eggs

Post by Colour_the_sky »

I see Lloyd but I don´t want to use excess Al more like the right amount in combination with MgAl. I want to see If that is louder than added Ti. Getting the silver spark shower after a better explosion that is what I aim for. The delay is the only thing that I don´t want to getting much longer.
User avatar
richardh08
Site Admin
Posts: 2226
Joined: Wed Aug 07, 2013 1:54 pm
Location: Bedfordshire

Re: Crackle mix/dragon eggs

Post by richardh08 »

There was a recent discussion on FW that got round to talking about ‘Time Rain’ (70% CuO, 20% MgAl, 10% Ti), which is one of the formulations that Colour_the_sky tried a few months ago. I first saw that composition in a thread on APC some 2 to 3 years ago, but never got round to giving it a go. The one on FW used an additional 6% of phenolic resin as the binder, which ties in with some of the experiments I’ve been doing, so I decided it was time to make a sample and see how it behaves.

I made approximately 4mm grains, using my ‘standard’ sub 250 mesh magnalium, and added a heavy layer of either rough BP or one of my ‘hotter’ and more slaggy primes. Both worked well in ground tests. With BP, there was a very short delay (about 1 sec) followed by a kind of ripping sound, accompanied by lots of white sparks; quite impressive. Curiously, with the other prime the delay was much longer (about 3 seconds) but the grain’s burn time was shorter, with a much sharper sound – very close to a true crackle.

I’ll have to see what they look like in the air, when not primed but included in a matrix composition.
Even when I'm wrong, I'm convincing.
Mixer
Posts: 31
Joined: Wed Mar 01, 2017 9:49 am

Re: Crackle mix/dragon eggs

Post by Mixer »

Here`s an interesting video - pity they don`t give the formulation!

https://www.youtube.com/watch?v=YeBq6CGW4TA
User avatar
Pyro-Gear
Site Admin
Posts: 3034
Joined: Wed Jul 10, 2013 8:24 am

Re: Crackle mix/dragon eggs

Post by Pyro-Gear »

Ah yes the old magic mix as sold on their website, not sure on this one Mixer.
Mixer
Posts: 31
Joined: Wed Mar 01, 2017 9:49 am

Re: Crackle mix/dragon eggs

Post by Mixer »

Hmm, the buggers like to keep us guessing :x
User avatar
Pyro-Gear
Site Admin
Posts: 3034
Joined: Wed Jul 10, 2013 8:24 am

Re: Crackle mix/dragon eggs

Post by Pyro-Gear »

Looking at the video it would seem that the binder was water soluble, I have seen a demonstration somewhere but I am not convinced if that was what the guy was making Mix. :)
User avatar
richardh08
Site Admin
Posts: 2226
Joined: Wed Aug 07, 2013 1:54 pm
Location: Bedfordshire

Re: Crackle mix/dragon eggs

Post by richardh08 »

richardh08 wrote: Fri Jan 25, 2019 4:32 pmI’ll have to see what they look like in the air, when not primed but included in a matrix composition.
Unprimed Time Rain grains didn't ignite, either in the air or on the ground, when included in a star made with Hardt's matrix composition.

I'll have to try again with primed grains.
Even when I'm wrong, I'm convincing.
Mixer
Posts: 31
Joined: Wed Mar 01, 2017 9:49 am

Re: Crackle mix/dragon eggs

Post by Mixer »

Richard, did you have any luck with the primed grains - especially in the air with single cores?
User avatar
richardh08
Site Admin
Posts: 2226
Joined: Wed Aug 07, 2013 1:54 pm
Location: Bedfordshire

Re: Crackle mix/dragon eggs

Post by richardh08 »

Oops! Thanks for the reminder.

So far, I haven't got round to trying it. Too many distractions/other projects on the go! I'll have to try and make some time to give it a go.
Even when I'm wrong, I'm convincing.
Post Reply