NightHawkInLight Posted January 15, 2011 Posted January 15, 2011 (edited) would using pulverone (Which also gives a nicer break) give you the structural integrity you need (its what I use and havent had problems) its probably better for 2 reasons 1 it doesn't have give so when pressure is allied your cut stars cant be pushed aside into the break area 2 it is somewhat of a solid column running up the middle of the shell which is unbendingThat is a big reason why pulverone or other granular black powder is most often used in canister shells. It increases strength greatly, but even then, in tall multibreaks a strong core may not be enough to keep the shell from folding in half. A wall of strong pumped stars or comets built around the casing provides excellent support right where it's most needed. I love cut stars, and I almost exclusively use them, but if I were making a shell for competition I would use pumped stars in all but possibly the top break. Now, inside of that wall of pumped stars, you can feel free to throw in another layer or two of cut stars. That strength right up against the wall of the can really helps though. I've had many a failure of a center break trying to prove otherwise. Edited January 15, 2011 by NightHawkInLight
dagabu Posted January 15, 2011 Posted January 15, 2011 would using pulverone (Which also gives a nicer break) give you the structural integrity you need (its what I use and havent had problems) its probably better for 2 reasons 1 it doesn't have give so when pressure is allied your cut stars cant be pushed aside into the break area 2 it is somewhat of a solid column running up the middle of the shell which is unbending Yes, coated rice hulls compress and give flowerpots when shot from mortars but in rocket headings it seems to work fine.
Mumbles Posted January 18, 2011 Posted January 18, 2011 I've seen and used shells broke with the burst coated on rice hulls or other media. They work just fine, but with larger shells and more breaks it makes me a bit nervous. Breaks longer than 1 diameter of just cut stars can tend to break out the ends if care is not taken. With good techniques it will be fine, but perhaps less forgiving as a shell as tall as it is wide.
dagabu Posted January 18, 2011 Posted January 18, 2011 Pumped stars Mum? Then I would agree but what about round or cut stars? I doubt they have the rigidity for a mortar shot.
Mumbles Posted January 18, 2011 Posted January 18, 2011 I was speaking of stars loosely filled into the casing, not stacked neatly around the perimeter. Pumped stars should probably work fine loosely filled as they get locked in with the polverone packing. I've seen and used round stars used successfully, but again it makes me feel a bit nervous. With smaller shells it's probably not as big of a deal as larger shells. I'd have no problem using round stars in a pistil in there were shell inserts or comets lining the outside of the break. Well no more problem than I'd feel a little dirty for using them in a can shell.
Guest no6 Posted January 20, 2011 Posted January 20, 2011 At the moment I'm making the very beautiful and exotic high end former seen here: My link
dagabu Posted January 20, 2011 Posted January 20, 2011 At the moment I'm making the very beautiful and exotic high end former seen here: My link Psssst! Soda Pop cans work better! Just sayin...
Guest no6 Posted January 20, 2011 Posted January 20, 2011 Psssst! Soda Pop cans work better! Just sayin... You're just jealous. See my post in suppliers.
Guest no6 Posted January 20, 2011 Posted January 20, 2011 My canister shell former is finished. This former is specific to my Wolter tooling and tubes. I used a 3/4" oak dowel with duct tape carefully rolled onto it (see previous link) then drilled it per the instructions in the link. I made the canister 2" wide. Any bigger seems out of proportion. Oh, and the dowel ends were painstakingly radiused by hand. It really is a guilty pleasure to possess such a fine tool.
dagabu Posted January 20, 2011 Posted January 20, 2011 Ohhhhhhh, sorry, I thought you were making real tools. That was cruel, all in jest.
Guest no6 Posted January 20, 2011 Posted January 20, 2011 Ohhhhhhh, sorry, I thought you were making real tools. That was cruel, all in jest. You must have missed the part about the radiused edges.
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