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whitepyro
06-18-2011, 02:09 AM
in the veline colour system redgum is used as one of the binders.could Gum Arabic be used instead?

californiapyro
06-18-2011, 11:28 AM
dont know bout gum arabic, but saran and pvc can be subs i know

Ralph
06-21-2011, 09:19 PM
dont know bout gum arabic, but saran and pvc can be subs i know

offence but just dont say stuff unless you actually do know. have you done any work on developing your own stars ? saran and PVC would be terrible replacments for redgum

dextrin is the binder in the veline compositions so the only requirements for a replacement is to have similar fuel value and burn characteristics some suitable replacements would be

lactose (especially in the blue) it burns slightly cooler than red gum but ignites more easily would be slightly inferior in the green
Potassium benzoate would be quite suitable though I wouldnt use it in the blue (if possible)
hexamine would be alright
shelac would work quite whell too (and is fairly similer to red gum)

I hope you didnt try this formula with added pvc or saran the formulla would not have been suitable for stars they would easily have the flame blown out as they travelled through the air

lastly I recomend you look for some better star comps veline comps are by admition of the creator not very good

californiapyro
06-21-2011, 09:53 PM
offence but just dont say stuff unless you actually do know. have you done any work on developing your own stars ? saran and PVC would be terrible replacments for redgum

dextrin is the binder in the veline compositions so the only requirements for a replacement is to have similar fuel value and burn characteristics some suitable replacements would be

lactose (especially in the blue) it burns slightly cooler than red gum but ignites more easily would be slightly inferior in the green
Potassium benzoate would be quite suitable though I wouldnt use it in the blue (if possible)
hexamine would be alright
shelac would work quite whell too (and is fairly similer to red gum)

I hope you didnt try this formula with added pvc or saran the formulla would not have been suitable for stars they would easily have the flame blown out as they travelled through the air

lastly I recomend you look for some better star comps veline comps are by admition of the creator not very good

yes I have. they both work. Shellac and Saran would work, but are both expensive compared to saran and pvc. as for lactose and benzoate, by your own admission they don't work in some comps, which is not an acceptable solution.

Ralph
06-21-2011, 11:16 PM
saran and PVC are chlorine donors they have poor fuel value and are retardents you cant use them to replace a fuel !!

I didnt say they wouldnt work just that they are less favourable (massive difference) slightly inferior means will still function doesn't work means wont work

also I dont know where you buy your pyro chems but shelac is generally cheaper than saran as are the other organics I mentioned , chlorinated compounds are usually quite expensive (with the exception of PVC in some cases due to is massive demand in other industries)

whitepyro
06-22-2011, 02:04 AM
cheers ralph ill use my benzoate that ive got and i will be making blue and green stars which will work well with what you said. And ill look for some other star comps

Ralph
06-22-2011, 02:09 AM
Just wondering is buying red gum out of the question its only $10 per pound at hobby chem http://www.hobbychemicalsupply.com/servlet/the-4/red-gum-acacia-gum/Detail

search for pyroscience blue and pihko kp blue but if you want really nice deep blues Ammonium perchlorate is the way to go

Pyrocity
06-22-2011, 09:00 AM
For making cut stars, skip the dextrin entirely and use acetone for solubilizing the parlon in the mixture. Works great!

Pyro@Mach13
06-22-2011, 09:40 AM
peace on rye!

pyropep
06-26-2011, 11:14 AM
For making cut stars, skip the dextrin entirely and use acetone for solubilizing the parlon in the mixture. Works great!

If your going to do that why waste the time cutting them when screen extrusion is so much faster?

pep

Chris H
06-30-2011, 07:51 PM
Are you just out of red gum and looking for a temporary fix, or can you not get it and are looking for a permanent solution?

I happen to agree that saran and PVC would be poor substitutes for red gum in this case. Saran has okay fuel properties for a chlorine donor, but this is compared to PVC and Parlon which are terrible fuels. Parlon is actually a fire retardant, and pure PVC probably isn't that far behind.

Red gum is not intended to be a binder in the Veline system, nor most any other formula you see it in. In this case it is a fuel, so it would be smart to replace it with another fuel. Shellac should work, but is generally considered to be not as good in perchlorate oxidized systems. Phenolic resin or vinsol would probably be the best replacements, but typically rather hard to come by.

I would actually take a combination of Ralph's advice, and use a 50/50 mix of Potassium Benzoate and Lactose. It will get you in the ball park of red gum. I've used this in a formula extremely similar to Veline red with good success. This was originally recommended on PML from Steve.......I really can't remember his last name. He uses the cbcasa.com domain name in his e-mail address.

whitepyro
07-02-2011, 01:02 AM
Yeah its for a permanent fix as i can not get it here. Ill go with the 50/50 mix of sodium and shellac

Chris H
07-03-2011, 03:16 PM
I hope you like yellow stars. The benzoate thing ONLY works if you can get potassium benzoate as it doesn't produce much light of it's own. Using sodium benzoate will over power nearly every color.