Merlin Posted June 13, 2015 Posted June 13, 2015 The instructions on passfire for 4 inch plastic hemis are to use two baggies filled with stars - one in the upper half and one in the lower half. The break charge is 40 grams of BP in both the upper and lower for a total of 80 grams. In addition, 5 grams of flash, which must refer to 70/30 standard, in a central bag. He does not tape or paste the shells only uses PVC to seal so it makes sense you would have to have a strong quick break but this seems like a lot of break charge. I know if you paste the shells properly you can escape the blinding flash and use only BP for break but this references only plastic hemis. What are your thoughts on the amount of break?
db5086 Posted June 13, 2015 Posted June 13, 2015 Just fill it with 7/1 bp rice hulls and dust with 3g whistle mix. That will give you a nice strong break and your stars should not blow blind. 5 g of flash seems to much but then again I seldom ever mess with it.
nater Posted June 14, 2015 Posted June 14, 2015 Lloyd who wrote that article is a true pro. He has that project with the plastic hemis well dialed in. When I start a new project like that, I always follow the instructions as they are written. You can change things next time, but it is good to copy all the steps first.
Merlin Posted June 18, 2015 Author Posted June 18, 2015 (edited) Ok I have produced five of these shells per instructions. I only hope they hold together in the tube. But clearly no pasting or fiberglass tape is recommended. I wont know til the forth when they are fired along with a variety of others, rockets, mines etc. Right now it is fearfully dry in North Alabama so I wont test until it rains someday. Edited June 18, 2015 by Merlin
nater Posted June 18, 2015 Posted June 18, 2015 We (NE Indiana) are getting a ton of rain and have a lot of flooding. More is coming to us this weekend from the remains of the hurricane in Texas. Hopefully you can get your shells up safely. Good luck on the 4th, I am sure they will function well if you followed the instructions.
Mumbles Posted July 5, 2015 Posted July 5, 2015 Merlin, did you get a chance to test the shells out? Lloyd's method is simple and expedient, but actually has worked pretty well for me the few times I tried it in the past.
insutama Posted July 5, 2015 Posted July 5, 2015 what did you glue the plastic shells with ? pvc cement ?
Sparx88 Posted July 5, 2015 Posted July 5, 2015 The best thing to use is this::: http://www.industrialplasticsnyconline.com/ProductDetails.asp?ProductCode=Acrylic+Solvent
insutama Posted July 5, 2015 Posted July 5, 2015 i cant find methylene chloride anywere locally so frustrating i cant find anything locally i cant even find calcium carbonate here in this town.
nater Posted July 6, 2015 Posted July 6, 2015 Tenax 7R and similar products sold as solvent plastic weld are methylene chloride. If you have a local hobby shop look around and you might find what you need. http://www.amazon.com/gp/aw/d/B00EMXTBG0/ref=mp_s_a_1_1?qid=1436141002&sr=8-1&pi=AC_SY200_QL40&keywords=tenax+7r&dpPl=1&dpID=41c8xkiKRbL&ref=plSrch
Merlin Posted July 6, 2015 Author Posted July 6, 2015 (edited) The first two are 4 inch shells, a 3 inch insert can and a crossette. Hope this turns out never tried attaching videos before. IMG_1214.MOV IMG_1215.MOV IMG_1195.MOV IMG_1188.MOV Edited July 6, 2015 by Merlin
Wiley Posted July 6, 2015 Posted July 6, 2015 (edited) Those 4" shells were very nice! I love long-burning colors, and I gotta say, those stars looked amazing, particularly the green and glitter. Can you tell us more about the cylinder shell, and the inserts you used? P.S. All the cool kids build salamis. Edited July 6, 2015 by Wiley
Merlin Posted July 6, 2015 Author Posted July 6, 2015 That is very kind of you to say. I hope to improve next year so I am getting Technique in Fire, Volume 2. Design and Quick Assembly of 3, 4, and 5 Inch Plastic Ball Shells by Ofca and study some more. The red was lithium carbonate and the green barium nitrate cut stars. The can shell of which I made two was an experiment. I got some hollow star pumps from Caleb and pumped 3/4 inch D1 glitter and filled the cavities with 70/30 and a piece of fast fuse(maybe not necessary) and capped them with end disc. I stacked them round the perimeter of a 3 in can (didnt have any 4's) and filled the center with hot BP. Fired them with 20g BP for lift. I did put a 3 inch end disc on the fuse side of the can for a bit more strength and wrapped the sides with fiberglass tape and covered with gummed tape leaving the top as is. When I have fired can shells naked they always blow out the bottom and I wanted them to blow out the top. I have to clean up the mess today when I cut grass so I should retrieve the remnants of the cans and see what happened. My next project (which I dread) is assembling a HF cement mixer to roll stars for next year. The five inchers are gonna take a lot of stars.
braddsn Posted July 7, 2015 Posted July 7, 2015 Merlin, those shells are very impressive sir! Nice rising comets as well!
DaMounty Posted July 7, 2015 Posted July 7, 2015 i cant find methylene chloride anywere locally so frustrating i cant find anything locally i cant even find calcium carbonate here in this town. Check your local hardware store for: http://www.rona.ca/images/0776170a_M.jpg DaM
insutama Posted July 7, 2015 Posted July 7, 2015 Check your local hardware store for: http://www.rona.ca/images/0776170a_M.jpg DaMis this pure methylene chloride ?
Merlin Posted July 7, 2015 Author Posted July 7, 2015 is this pure methylene chloride ?you can get methylene chloride at amazon, ebay or skylighter
insutama Posted July 7, 2015 Posted July 7, 2015 ya i just wanted to get it locally so i dont have to pay 30$ for shipping on a 10$ item
insutama Posted July 8, 2015 Posted July 8, 2015 i found some circa 1850 in town and bought some seems to work good thanks for that damounty
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