olac170 Posted July 31, 2012 Posted July 31, 2012 Hello, my parlon stars are very crumbly when they're wet. I think I used way to much acetone too (44 grams of acetone for 100 grams of star comp). Any advice would be appreciated and thank you in advance.
nater Posted July 31, 2012 Posted July 31, 2012 If you used too much acetone, the comp will turn into a gooey mess. The nice thing about using acetone, is that if you add too much, all you need to do is let some evaporate. Then cut the stars when it is about like modeling clay.
olac170 Posted July 31, 2012 Author Posted July 31, 2012 How much acetone should I use? Im using skylighters radiant green stars: 40 Potassium perchlorate30 Barium carbonate15 Bright flake 325 mesh aluminum15 Parlon
nater Posted July 31, 2012 Posted July 31, 2012 How are you making the stars? I have had the best luck cutting parlon bound stars, screen slicing was messy and I could not get consistant sizing. My answer is: add "enough" acetone so that when your stir it in to the comp, you can knead it and cut it. Too much is okay, because it will evaporate quickly. I just re-read an article about parlon stars by Troy Fish. He says the minium amount of acetone to activate the parlon is about 25%. Best moisture resistance occurs when the mixture has nearly been liquified; approximately 40% solvent. You will have to stir this until some of the acetone evaporates and the mixture becomes more firm before you can cut it. I was pointed to his article by a master pyro. It was originally printed in Pyrotechnica VII, if you are serious about parlon / acetone stars it is a good reference. I am still a beginner myself, but I have made several batches of color stars using G. Smith's screen sliced star formulas along with the techniques in that article.
Bangkokpyro Posted July 31, 2012 Posted July 31, 2012 (edited) IMO 44 gms of Acetone in 100gms of comp is way too much and should result in a stringy mass like soft chewing gum that is too soft to make cut stars.I use about 250 ml Acetone per kilo of comp, knead it together then cover with a plastic bag for 5 minutes. After a final kneading it is ready to pound into a slab and cut.Once I had a batch of crumbly Parlon mix and added more and more Acetone trying to get it to become tacky; it didn't. and remained crumbly.I later discovered the Acetone had absorbed a load of water, this might be the cause of your problem. Edited July 31, 2012 by Bangkokpyro
dan999ification Posted July 31, 2012 Posted July 31, 2012 iirc without my notes i used 25-35ml per 100g of comp but have purposely made veline like thick cream and poured it into bombettes it sets up just fine if a little porous, let it dry until you can form it and cut it. dan.
olac170 Posted July 31, 2012 Author Posted July 31, 2012 IOnce I had a batch of crumbly Parlon mix and added more and more Acetone trying to get it to become tacky; it didn't. and remained crumbly.I later discovered the Acetone had absorbed a load of water, this might be the cause of your problem.How do I get the water out of my acetone?
Potassiumchlorate Posted July 31, 2012 Posted July 31, 2012 You have to destillate the water out. There is a little water in all acetone, though that usually doesn't matter. It's worse when the acetone absorbs water from the air. It has been suggested to use toluen instead, because that is supposed to be 100% anhydrous, though I haven't tested that yet.
BJV Posted July 31, 2012 Posted July 31, 2012 How do I get the water out of my acetone? 3A molecular sieves BJV
olac170 Posted July 31, 2012 Author Posted July 31, 2012 It has been suggested to use toluen instead, because that is supposed to be 100% anhydrous, though I haven't tested that yet. Does anyone know if klean-strip xylene will work as a solvent for parlon?
Mumbles Posted July 31, 2012 Posted July 31, 2012 It will probably work, however I assure you that neither xylene nor toluene will be 100% anhydrous. They are not as bad about absorbing water as acetone however.
Bangkokpyro Posted August 1, 2012 Posted August 1, 2012 How do you distill acetone? http://chemistry.depaul.edu/aarena/Labs/231L-11-Lab1.pdf Not worth the effort, expence and danger involved in the procedure....... Just buy some good 'dry' Acetone of try the molecular sieve method
MondoMage Posted August 1, 2012 Posted August 1, 2012 I've heard that calcium chloride pellets (Damp Rid) will work as well. Anybody have any experience with that?
Potassiumchlorate Posted August 1, 2012 Posted August 1, 2012 I thought that "molecular sieve" was a joke at first.
BJV Posted August 1, 2012 Posted August 1, 2012 I thought that "molecular sieve" was a joke at first. You can buy molecular sieves here.BJV
AirCowPeacock Posted August 8, 2012 Posted August 8, 2012 I substituted SGRS/Watwr for Parlon/Acetone in Shimizu Silver wave to get it to dry faster, which of course it did, but the stars are very weak. Does it not work so well with metalic stars, or do I need more parlon?
Potassiumchlorate Posted August 8, 2012 Posted August 8, 2012 You need at least 7% parlon. It's considerably more brittle than SGRS.
Mumbles Posted August 8, 2012 Posted August 8, 2012 Parlon is about the least brittle thing I know of that's used in pyro. I really have no idea what you're talking about. Many people recommend no less than 12-15% parlon if you're going to use it as a binder, though that seems rather high to me. At that level it may screw up a formula such as silver wave. It's a drastic change over subbing a few parts here or there in a colored star. Alternatively, as mentioned before, your acetone could be fairly wet.
AirCowPeacock Posted August 9, 2012 Posted August 9, 2012 I think its plenty dry enough. Unless it gained 3% water since I last made stars before with it--a few days prior. Or lost that 3% water just yesrerday a few days later. It must be the amount than. I could add a stociometeic amount of KP to keep the formula more intact. But next time Ill just use dextrin--I was pressed for time then.
Potassiumchlorate Posted August 9, 2012 Posted August 9, 2012 Parlon is about the least brittle thing I know of that's used in pyro. I really have no idea what you're talking about. Many people recommend no less than 12-15% parlon if you're going to use it as a binder, though that seems rather high to me. At that level it may screw up a formula such as silver wave. It's a drastic change over subbing a few parts here or there in a colored star. Alternatively, as mentioned before, your acetone could be fairly wet. Excuse my English. "Brittle" wasn't the right word. But as you say, you do need more parlon than SGRS or dextrin, which is what I meant.
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