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D1 glitter star problem, advice needed


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Hi everyone - I've been trying to make D1 glitter stars using the standard recipe and first I used water + IPA as solvent, and used so little that the wet compound would not stick to my fingers and was quite stiff. The stars turned out extremely brittle, they would break from the slightest squeeze.

 

I figured that if I used water only, and used more of it, so that the compound would be sticky, then the dextrin would soak up more water and bind better. This time I put the stars to dry in a warm place, but noticed that they are swelling, because the sodium bicarbonate is reacting with water, forming CO2 gas. The funniest thing happened when I tried what would happen if I put one star in 180C oven for 10 minutes. It dried and hardened all right, but also swell to at least 10x original volume, becoming as light as styrofoam. That is why they call it baking soda I guess.

 

Any suggestions? I have a third batch of the dry mix ready, what should I do to make this work?

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My tips regarding D1 and N1 glitter, or any composition using Bicarbonate in that regard.

 

Dont force dry it in a hot drying chamber, they will swell, start to smell to Sulfur and will indeed become brittle. And you will have high chance the Ai is gonna react with the Nitrate because of the Bicarbonate in it. Mumbles probaly can jump in here as too why this is more prone to happen with the Bicarbonate. I usualy dont have any reaction with Ai and Nitrate, except in some glitter formula's calling for Sodium Bicarbonate.

 

Just let them dry in warm air, like max 20C, with a little wind blowing over it, like a small fan. It will take longer, but its worth it. It all depends in your star size. For example, 10mm stars will take atleast a couple weeks to fully dry. They will look dry after a week, but you can easily crumble them between your fingers. Using IPA with water will speed the drying up.

 

Just have some patience with them, let them dry for a couple more days/week(s)

Edited by redbullzuiper
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Thanks redbullzuiper - I am going to do as you recommended with the new batch.

 

The stars smell pretty bad, I assume that is hydrogen sulfide. Is that supposed to happen, and is it a problem?

 

Do you have a recommendation about how wet to make the compound? Should it be quite dry, so that it does not stick to your hands, or should it be sticky?

 

Also, I would like to be able to have them ready by New Year, do you suppose it would be OK to dry them in room temperature for, say, a week, and then do the final drying in an oven?

 

 

 

My tips regarding D1 and N1 glitter, or any composition using Bicarbonate in that regard.

 

Dont force dry it in a hot drying chamber, they will swell, start to smell to Sulfur and will indeed become brittle. And you will have high chance the Ai is gonna react with the Nitrate because of the Bicarbonate in it. Mumbles probaly can jump in here as too why this is more prone to happen with the Bicarbonate. I usualy dont have any reaction with Ai and Nitrate, except in some glitter formula's calling for Sodium Bicarbonate.

 

Just let them dry in warm air, like max 20C, with a little wind blowing over it, like a small fan. It will take longer, but its worth it. It all depends in your star size. For example, 10mm stars will take atleast a couple weeks to fully dry. They will look dry after a week, but you can easily crumble them between your fingers. Using IPA with water will speed the drying up.

 

Just have some patience with them, let them dry for a couple more days/week(s)

 

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The stars smell pretty bad, I assume that is hydrogen sulfide. Is that supposed to happen, and is it a problem?

Yes, happens most of the time with that type of stars. Don't worry about it, it will go away when they dry.

 

 

 

Do you have a recommendation about how wet to make the compound? Should it be quite dry, so that it does not stick to your hands, or should it be sticky?

Do you roll, pump or cut them? According to some people the effect can be disturbed when too much water is used, I roll all stars so Ive no experience this issue.

I guess you are cutting your stars based on what you said, they should be a bit sticky, just enough so you can make a ball with it. But not too sticky, else you have a hard time cutting nice cubes.

 

I guess you use Dextrin? For me, SGRS always have been easier to work with for cut stars. Dextrin can be pretty sticky.

 

 

 

Also, I would like to be able to have them ready by New Year, do you suppose it would be OK to dry them in room temperature for, say, a week, and then do the final drying in an oven?

Let them dry for a few more days, and check after if they are starting to get hard. I would never suggest to put stars into an oven, as the stars might ingite because of the heat. Thats just too risky, unless you have the oven somewhere, which incase of an accident, is at a safe location. Still, I would not put stars into an oven.

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I pumped them into cylindrical stars using a disposable syringe with the end cut off, and a box cutter blade. Do you have any priming suggestions? I have been using liquid H3 primer with my other stars with good results, but I am weary about its safety, considering the very high sulfur content of D1 stars. I have been thinking about making a liquid primer with BP with some added dextrin, and perhaps some sawdust to make the surface rough, which would facilitate easier ignition. What do you think about this plan?

 

Yes, happens most of the time with that type of stars. Don't worry about it, it will go away when they dry.

 

Do you roll, pump or cut them? According to some people the effect can be disturbed when too much water is used, I roll all stars so Ive no experience this issue.

I guess you are cutting your stars based on what you said, they should be a bit sticky, just enough so you can make a ball with it. But not too sticky, else you have a hard time cutting nice cubes.

 

I guess you use Dextrin? For me, SGRS always have been easier to work with for cut stars. Dextrin can be pretty sticky.

 

Let them dry for a few more days, and check after if they are starting to get hard. I would never suggest to put stars into an oven, as the stars might ingite because of the heat. Thats just too risky, unless you have the oven somewhere, which incase of an accident, is at a safe location. Still, I would not put stars into an oven.

 

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Well, its a bad idea to prime these stars with a prime containing chlorate, sounds like you have to do some more research if you dont want accidents.

 

Anyway, there are tons of primes. D1 glitter is not hard to ignite, a simple black powder prime will do.

If you want a more general purpose prime, which ignites most stars, add 8% Sillicon or Red Iron Oxide to black powder.

 

I use this prime most of the time

KNO3..............68

C..............13

S..............10

Si..............9

SGRS/Dextrin/Gum Arabic..............+4

 

Or leave the binder and instead disolve 4% of Gum Arabic in a solution. This will create rock hard stars suitable for hard flash breaks.

 

Another good prime, and probaly the best one is the monocapa prime by JOPETES.

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Thanks for the recipe!

 

What do you think about the sawdust idea? It creates spikes or roughness on the surface, and thus facilitates easier ignition.

 

What purpose does the silicon or red iron oxide serve in a primer? I don't have silicon but I do have red iron oxide, would it work the same?

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Sawdus and Diatomaceous Earth in a prime creates more surface area to catch fire. It is not neccesary tho. See Fence Post prime or Veline's prime.

 

Silicon or iron oxide create hot slag on the star which helps ignite the star. Red iron oxide instead of silicon works just fine, I never notice a difference between using the two.

Edited by redbullzuiper
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Hi everyone - I've been trying to make D1 glitter stars using the standard recipe and first I used water + IPA as solvent, and used so little that the wet compound would not stick to my fingers and was quite stiff. The stars turned out extremely brittle, they would break from the slightest squeeze.

 

I figured that if I used water only, and used more of it, so that the compound would be sticky, then the dextrin would soak up more water and bind better. This time I put the stars to dry in a warm place, but noticed that they are swelling, because the sodium bicarbonate is reacting with water, forming CO2 gas. The funniest thing happened when I tried what would happen if I put one star in 180C oven for 10 minutes. It dried and hardened all right, but also swell to at least 10x original volume, becoming as light as styrofoam. That is why they call it baking soda I guess.

 

Any suggestions? I have a third batch of the dry mix ready, what should I do to make this work?

Your using too much water. The comp should not feel sticky or stiff at all. In general, 4-6% distilled water, works well for pumping with dex. If your hand ramming larger comets ( 1-1/4" + ) using slightly more water 7-8% can be helpful. The comp and water should be sceened mixed 2-3 times. Then tempered at least an hour, 2 is better. The comp should then be screened another time or two. 8 to 4 mesh for dampened comp works well. Once it's well incorporated, and tempered properly. It should have a very consistant texture, somewhat similar to loose brown sugar.

 

When you're drying stars. Airflow is more important than heat. The first few days to a week should only be air flow. You will avoid alot of issues like this. If you pull the majority of water out of your stars. Before you apply gentle heat, WITH AIR FLOW. They'll be alot less likely to have a reaction. Using a household oven is asking for trouble or an injury.

Edited by Carbon796
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Thanks Carbon796 - Do you know if using too much water changes the performance of the stars, or does it only affect the drying time? If I use only very little water, how can the stars harden properly? They must be hard to withstand the burst.

 

Your using too much water. The comp should not feel sticky or stiff at all. In general, 4-6% distilled water, works well for pumping with dex. If your hand ramming larger comets ( 1-1/4" + ) using slightly more water 7-8% can be helpful. The comp and water should be sceened mixed 2-3 times. Then tempered at least an hour, 2 is better. The comp should then be screened another time or two. 8 to 4 mesh for dampened comp works well. Once it's well incorporated, and tempered properly. It should have a very consistant texture, somewhat similar to loose brown sugar.

When you're drying stars. Airflow is more important than heat. The first few days to a week should only be air flow. You will avoid alot of issues like this. If you pull the majority of water out of your stars. Before you apply gentle heat, WITH AIR FLOW. They'll be alot less likely to have a reaction. Using a household oven is asking for trouble or an injury.

 

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Very little water, would be like 3.5% or less.

 

Using excessive water can change the look of the tail. It will also make a comp more likely to have a reaction, if it is so inclined. 5% water my not lend a comp to reacting, but 10% may. Ambient temperature, and duration of time being "wet" are also factors.

 

Your stars are not getting hard for probably three reasons. They are probably not fully dry. Dex is known to not gain full strength until they are fully dry, or very close too. Until then they can sometimes be quite fragile. The less consolidated they are, the more noticeable this is.

 

Consolidation pressure. Using a plastic syringe with hand pressure only. Will not produce stars as durable as hand ramming or pressing. Not that they can't be usable, but they have limits.

 

The use of too much water with/and/or excessive heat, is causing the comp to react. Which is compromising the star comp and integrity.

 

The goal, is to use just enough water to activate the binder well. And achieve good consolidation. Then pull the water back out of the stars with air flow in a timely manner.

 

The wetter a comp is, the longer it is wet, and the higher the ambient temps are. The more prone a comp will be to have a reaction, if it is capable of having one.

Edited by Carbon796
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