Making stars, red gum,dextrin or parlon binder?

[Sparx88]

I have a couple comps for blue that I'm trying but they call for red gum. I don't have that. Can the red gum be sub with dextrin or can I leave both out and just bind with the parlon/acetone? I need hard fast burning stars.

 

I have Cu0, kc104 parlon, and dextrin.

 

recipe I got is;

 

63 PPerc

13 BCOxide

14 parlon

10 red gum

 

 

[LambentPyro]

The Red Gum is the primary fuel of that formula, switching it may not give you ignition.

 

If you're looking for fast burning stars, it'd be a good idea to switch to metallic fueled stars such as Veline. However, the metallic Blues are pretty shitty compared to formulas such as Pihko, which uses Red Gum as the fuel.

 

Red Gum is actually a poor binder. A good idea would be to add 4-5% Dextrin to that formula and get yourself Red Gum. You need Red Gum if you want to make excellent quality stars, it's just one of those things that's quite expensive, but can't really be subbed for another chem besides Rosin and Shellac which, IIRC, can ruin the stars.

Edited February 4, 2014 by LambentPyro

[nater]

Red gum is a perfectly good binder. Red gum can be subbed 1:1 with shellac and certainly does not ruin the stars.

[LambentPyro]

Red gum is a perfectly good binder. Red gum can be subbed 1:1 with shellac and certainly does not ruin the stars.

Actually, it's a terrible binder and I paraphrased from Mumbles in this thread:

http://www.amateurpyro.com/forums/topic/2462-red-gum-substitute/?do=findComment&comment=32616

[Mumbles]

I find it to be a sub-par binder, especially in comparison to dextrin. In any case, the formula posted originally had 4-5 parts of dextrin in it anyway, and was meant to be bound that way.

 

There are a few options to replace the red gum. Besides shellac and rosin, which have already been mentioned, there is also Vinsol resin, and phenolic resin. They might not all be 1:1, but it shouldn't take too much effort to dial in a good formula.

[nater]

Actually, it's a terrible binder and I paraphrased from Mumbles in this thread:

http://www.amateurpyro.com/forums/topic/2462-red-gum-substitute/?do=findComment&comment=32616

Try it for yourself and report back. Ned, myself and others use it regularly with pressed stars. They dry rock hard with no issues.

[Sparx88]

What about charcoal, will that fuel the comp enough? Or charcoal plus sulfur?

 

 

Do the red gum comps need alcohol mix or water?

 

 

 

63 PPerc

13 BCOxide

14 parlon

10 red gum

6% dextrin <-------- If i was to add dextrin to that comp and rolled the stars, should it be water or 50/50?

 

Or would using acetone to bind with parlon while rolling be good? I tried doing that and they got all gummy and clumped almost immediately. I then tried it with 50/50 alc wat and they broke easy when dry. And they all are very slow burning. So I did a test to see if the perchlorate was bad and it was actually fantastic so that's ruled out.

 

 

[Mumbles]

You know, I'd love to find out where people get the idea that a 50/50 mix of alcohol and water is in anyway a good idea for activating any binder. A formula with dextrin in it is meant to be bound with water, or at the very least a water rich mixture with alcohol. If you go more than probably 25% alcohol you really start to get into the realm where activation and binding strength will be affected. There is absolutely zero truth to the idea that using both alcohol and water will activate both the dextrin and the red gum.

 

No, charcoal or a mix of charcoal and sulfur won't work, at least in the formula as written. You really need some sort of organic resin type of product for this type of formula. Given that it appears that you're from the US, perhaps you should just buy some. This isn't a hobby that takes kindly to blind substitutions. You need the right tools for the job.

 

I'd suggest against doing anything except cutting or screen slicing with acetone/parlon bound stars. It's just too sticky and stringy for other methods to work.

 

Might I suggest using a different formula instead? There is a good blue from Alexander Hardt's book that I think will fit your needs pretty well. I included the original just so you can see it, but there are some substitutions below with things you likely already have.

 

Hardt Blue #6

Potassium Perchlorate - 62

Sulfur - 18

Copper Oxychloride - 12

Dechlorane - 4

Dextrin - 4

 

 

Modification:

 

Potassium Perchlorate - 62

Sulfur - 18

Copper Oxide - 12

Parlon - 4

Dextrin - 4

 

Before getting too worried about the seeming lack of chlorine donor, you should know that using sulfur as the fuel liberates the chlorine from perchlorate. This composition will have to be bound with water. There probably isn't enough parlon to use acetone even if you tried.

[LambentPyro]

Try it for yourself and report back. Ned, myself and others use it regularly with pressed stars. They dry rock hard with no issues.

If it works for you, no argument there. I was speaking from what others had experienced, Red Gumis much more expensive than Dextrin, and I find Dextrin to be a good friend of mine (basically I've never had an issue with it) and would prefer in continuing to use it.

 

Like I said, if it works great for you, to each their own!

 

What about charcoal, will that fuel the comp enough? Or charcoal plus sulfur?

 

 

Do the red gum comps need alcohol mix or water?

 

 

 

63 PPerc

13 BCOxide

14 parlon

10 red gum

6% dextrin <-------- If i was to add dextrin to that comp and rolled the stars, should it be water or 50/50?

 

Or would using acetone to bind with parlon while rolling be good? I tried doing that and they got all gummy and clumped almost immediately. I then tried it with 50/50 alc wat and they broke easy when dry. And they all are very slow burning. So I did a test to see if the perchlorate was bad and it was actually fantastic so that's ruled out.

I would use a 25/75 mix of Isopropanol to water (by volume) as that way it will activate your primary/stronger binder and the red gum will still use the alcohol. Also, it will tend to dry faster than just using plain water, this is what I found in my experience to work.

 

Just make sure that you don't go past 7% Dextrin, Bleser reports this is a popular cause of stars becoming driven-in.

 

Good luck!

Edited February 5, 2014 by LambentPyro

[nater]

Dextrin is certainly cheaper than red gum, no arguments there. Water is almost free and does not have the hazards of alcohol fumes. I use alcohol / red gum exlusively with pressed strontium nitrate stars to avoid adding water to them. I use acetone / parlon if they will be cut or buttered into cavity comets. The alcohol / red gum method works well when pressing stars and is less messy than the dissolved parlon.

 

The only other advantage to pressing stars bound with red gum is when you need a fast drying time, like when building at club events. People also have good results using phenolic resin and alcohol for stars to be dried overnight as well.

 

 

Other than strontium nitrate stars and if stars need to dry overnight, I typically use a dextrin / water solution to bind stars. It is cheap and less irritating to work with.

Edited February 5, 2014 by nater

[LambentPyro]

Dextrin is certainly cheaper than red gum, no arguments there. Water is almost free and does not have the hazards of alcohol fumes. I use alcohol / red gum exlusively with pressed strontium nitrate stars to avoid adding water to them. I use acetone / parlon if they will be cut or buttered into cavity comets. The alcohol / red gum method works well when pressing stars and is less messy than the dissolved parlon.

The only other advantage to pressing stars bound with red gum is when you need a fast drying time, like when building at club events. People also have good results using phenolic resin and alcohol for stars to be dried overnight as well.

Other than strontium nitrate stars and if stars need to dry overnight, I typically use a dextrin / water solution to bind stars. It is cheap and less irritating to work with.

Good idea with the Strontium Nitrate bound with Red Gum/Alc. That damn Sr₂Cl impurity is a real PITA.

 

Yea, I tend to stay away from Acetone, and had only tried it once with the Parlon. It was making me sneeze like crazy, even outdoors!

 

For quick drying, Denatured bound dries extremely fast. I spilt a little on my kraft paper-covered work area and it dried out within 30 seconds at the most.

 

As far as using Phenolic, that's not an old idea, right? Using Phenolic Resin in common formulas was only proposed a few years ago IIRC.

Edited February 5, 2014 by LambentPyro