pyroguy1960 Posted November 9, 2010 Author Posted November 9, 2010 Oh yea...karl that helps me....there's only 988,989,334 karl's in the world.
FREAKYDUTCHMEN Posted November 9, 2010 Posted November 9, 2010 Yea for charcoal stars you'll need pine charcoal, certainly.
Algenco Posted November 9, 2010 Posted November 9, 2010 Oh yea...karl that helps me....there's only 988,989,334 karl's in the world. http://www.ubpyro.com/2010ChemPriceListPGI.pdf
pogue1000 Posted November 9, 2010 Posted November 9, 2010 Even i know who Karl is What did you use for burst on this shell JMS?
pyroguy1960 Posted November 9, 2010 Author Posted November 9, 2010 Thanks for the karl clarification PDF. I think I heard him mentioned somewhere before on here but decided to be a wise ass instead of looking around. The burst was perchlorate No.5 from FAST 1.3:1 on cotton seeds. No. 5 is: KCIO4 70Charcoal (I used commercial airfloat) 30SGRS or Dextrin 2%
Mumbles Posted November 9, 2010 Posted November 9, 2010 I wouldn't make these stars in those cheap chinese star plates. The FeTi will tear the plastic plate up. Actually it was this comp that I found that out the hard way in the first place. The mine I made with the commercial airfloat looked fine to me, but you can't really tell about tail hangtime when it's not way up there in the air.
pogue1000 Posted November 10, 2010 Posted November 10, 2010 I will heed your advice Mumbles and try not to get tempted to use it and just cut the stars ThanksI wouldn't make these stars in those cheap chinese star plates. The FeTi will tear the plastic plate up. Actually it was this comp that I found that out the hard way in the first place. The mine I made with the commercial airfloat looked fine to me, but you can't really tell about tail hangtime when it's not way up there in the air.
pyroguy1960 Posted November 10, 2010 Author Posted November 10, 2010 I wouldn't make these stars in those cheap chinese star plates. The FeTi will tear the plastic plate up. I used 40-325 FeTi and it didn't even scratch my Wolter plate. I expected to see some scoring in it when I was done, but really nothing...again can't recomend those plates enough....they are the shit and the coating they put on them really does protect them.
pyroguy1960 Posted November 10, 2010 Author Posted November 10, 2010 Here's a pic of the star plate: Oh and some of the shells I shot this weekend.
Mumbles Posted November 10, 2010 Posted November 10, 2010 I'd be careful with such fine FeTi. If the FeTi is of a certain fineness, it can get between the pins and body of the plate. This is when you get really deep scratches and seized plates. I don't know the clearance between the pins and the plate but I believe the values I've heard is get rid of particles smaller than twice the diameter of the clearance, or larger than 1/4th the clearance. Granulating the comp really helps to keep it from causing as much damage.
pyroguy1960 Posted November 10, 2010 Author Posted November 10, 2010 Hmmm, I did hear it crunching when I was popping them out, perhaps I was just lucky this time that it didn't do any serious damage to the plate.
dagabu Posted November 10, 2010 Posted November 10, 2010 Yeah, Ned has a drawing showing the clearances. Screen everything and keep what is larger then the gap x2. They cant get into the gap and scratch.
pyroguy1960 Posted November 10, 2010 Author Posted November 10, 2010 Yup he warned me about that as well and told me to screen out anything finer than 40 mesh. But at the end of the day, really what's the worse that could happen, the plate gets scored to all hell? Doesn't really matter at the end of the day, I don't think it would ever render it unusable and I could care less about cosmetic damage to a star plate.
dagabu Posted November 10, 2010 Posted November 10, 2010 What happens with smaller particles is that the plate jams and the attempt to open the plate results in bent/broken pins, warped/broken plate. The scratches are unfortunate but jamming is death.
pyroguy1960 Posted November 10, 2010 Author Posted November 10, 2010 Right on, well I'll keep you all posted if I ever get a death by jamming. Perhaps it's a good test for these plates to see if they ever do in fact jam beyond repair, I've pressed many many Ti stars with them so far and nothing.
fredhappy Posted November 10, 2010 Posted November 10, 2010 (edited) Hi fellow pyro's, Today I've made a 2 kilo batch of this golden streamer composition. It did not do any significant damage to my tooling, just a few minor scratches to my comet pump I guess. I've used a 10 ton hydraulic press and a 12 mm starplate. I could apply 2.5 tons of pressure at my starplate without any problems, all stars came out nice and firm. The amount of water I've used for pumping was about 20% water/alcohol solution (85 % water, 15 % alcohol). I've also made some 2 inch comets with my newly arrived comet pump. These are intended to be attached to my 5 inch shells, and a couple to just shoot out of a 2 inch mortar. Can't wait till everything is dry, this streamer is a beauty in my opinion. It was also a rather costly composition, since I've used about a pound of Fe-Ti...2 grades were used, ranging from 250-450 mesh. Edited November 10, 2010 by fredhappy
vladou Posted November 14, 2010 Posted November 14, 2010 I was wondering if I could replace the 25 parts of FeTi with 15 parts of Fe and 10 parts of sponge Ti ? Seems not a wise idea due to KNO3 presence but I don't have any FeTi. (neither boric acid)
Mumbles Posted November 14, 2010 Posted November 14, 2010 You can replace it with iron and titanium, but the effect wont be the same. I'm not saying it wont be good, but it wont be the same. Iron can be protected from potassium nitrate by coating it with paraffin or linseed oil. Titanium is fine in it's presence. Boric acid will not protect iron anyway, so it's not a big deal that you do not have it.
pogue1000 Posted November 18, 2010 Posted November 18, 2010 What size screen would be good to granulate comp for a star plate? I'd be careful with such fine FeTi. If the FeTi is of a certain fineness, it can get between the pins and body of the plate. This is when you get really deep scratches and seized plates. I don't know the clearance between the pins and the plate but I believe the values I've heard is get rid of particles smaller than twice the diameter of the clearance, or larger than 1/4th the clearance. Granulating the comp really helps to keep it from causing as much damage.
Seymour Posted November 21, 2010 Posted November 21, 2010 I don't think it will matter much, since all granulating does it makes the powder easier to handle before you press. If you are making very small stars, perhaps don't use very large grains. Otherwise, be free!
Mumbles Posted November 22, 2010 Posted November 22, 2010 It matters a little bit if you're using deep fill plates where 1 filling is supposed to be sufficient to press the star. I usually used a 12 or 16 mesh screen, about a window screen or kitchen strainer sized. It's pretty easy to get the comp through, and the grains stay together.
pogue1000 Posted December 6, 2010 Posted December 6, 2010 Made a batch of these but if i squeeze them to hard between my fingers they just shatter. Maybe I didnt get enough water in them? Or possibly that i just used a mallet and pressure on the star plate.. dunno. I was using 10% water.
pyroguy1960 Posted December 6, 2010 Author Posted December 6, 2010 My guess would be they're not completely dry yet, however I did use a 12 ton shop press to make mine, but I only used about half it's strength on the plate. I have noticed many times that if a batch of dextrin bound stars is not completely dry they will in fact crumble fairly easily when you squeeze them. 10% water is definately plenty, I only use about 5-7% water. Another solution would be to disolve a little gum arabic in the water to toughen em up a little more. You could even bind them with 3-4% SGRS as I hear it's a better binder than dextrin, but I have not tried that yet.
pogue1000 Posted December 6, 2010 Posted December 6, 2010 Now do yours crumble fairly easy after you use a press on them and take them out of the plate? I tried make a makeshift press out of wood and used a 12 ton bottle jack last night but it was just awkward trying to press them, hold a board to squeeze it, and the guage in there it just wanted to tip over lol. I am definitely going to pick me up a press here sometime because i am seeing it is a very important tool for this hobby. This winter is my time to really get organized with all my tools. I will let them dry a couple more days but then its getting pasted because we have a club shoot saturday and I cant come empty handed My guess would be they're not completely dry yet, however I did use a 12 ton shop press to make mine, but I only used about half it's strength on the plate. I have noticed many times that if a batch of dextrin bound stars is not completely dry they will in fact crumble fairly easily when you squeeze them. 10% water is definately plenty, I only use about 5-7% water. Another solution would be to disolve a little gum arabic in the water to toughen em up a little more. You could even bind them with 3-4% SGRS as I hear it's a better binder than dextrin, but I have not tried that yet.
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