PyroCube Posted March 31, 2013 Share Posted March 31, 2013 Hi all I`ve built a 3" ballshell recently. Pasting was done with 60g/sm kraft paper, 5 layers of it.My shell fits very loose in the mortar tube, there is still 1/4 inch gap around the shell.Should I do some more pasting? I thought about 10 layers but isn`t my paper too heavy for 10 layers, so it won`t shatter the stars? Thank you for your help, Greets Link to comment Share on other sites More sharing options...
pyrojig Posted March 31, 2013 Share Posted March 31, 2013 You are at the perfect size. Industry uses 1/4 smaller shells than the dia. of the tube. It is necessary to have space for the leader fuse to fit too. This gap will make very little diff in lifting to the correct height. Id suggest lifting it with 15-17g of 4f , or if you have hot riced bp like mine I use 13-15g. Link to comment Share on other sites More sharing options...
PyroCube Posted March 31, 2013 Author Share Posted March 31, 2013 There is actually a 1/4" gap all around the shell, the shell is 1/2" smaller than the mortar.I pasted a few more layers now, but the shell is still too small in my opinion.Is there a way to make the shell bigger without affecting the break symmetry?Maybe I should just wrap a few layers of masking tape around the shell? Greets Link to comment Share on other sites More sharing options...
busspuppy Posted March 31, 2013 Share Posted March 31, 2013 (edited) It really doesn't matter. I always have loose fitting ball shells. I say go light it you should be fine, if you are worried about it just add more lift, I wouldn't add more that 5g more than usual. You can get away with this on ballshells (if shell is built properly) because of the gaps. If it was a cylinder shell the correct lift is more critical since you don't have the gasses passing by the side of the shell.Take a video of the shell for all to enjoy! Another idea I just thought of that you can do, is to build a test shell to shoot. What you could do is fill a 3" hemi with powered chalk then tie a flash bag to burst the shell. It will make a nice dust cloud in the sky (don't be concerned if the cloud isn't big because the dust is so light). If you are not expierenced using flash or are just beginning please do not use flash. Use black powder instead, you will need more of it but it is much safer. Building the test shell will give you the chance to see what the shell will do before you light your 3" shell. It also allows you to dial the lift and time fuse down. P.S.You can add more layers if you want but you don't really need to. BTW what burst are you using? You might keep the burst type in mind. Edited March 31, 2013 by busspuppy Link to comment Share on other sites More sharing options...
PyroCube Posted April 1, 2013 Author Share Posted April 1, 2013 Hi I shot the shell yesterday, I think it turned out quite nice. http://www.youtube.com/watch?v=2Avn3GxhJ4I My stars could have been better, but I was satisfied with the break, since I haven`t used any booster or paulownia charcoal. (It was alder buckthorn) Greets Link to comment Share on other sites More sharing options...
AlexPyro66 Posted April 1, 2013 Share Posted April 1, 2013 Very nice shell can you share the white comp? Link to comment Share on other sites More sharing options...
dan999ification Posted April 1, 2013 Share Posted April 1, 2013 You did good Dan Link to comment Share on other sites More sharing options...
Oinikis Posted April 1, 2013 Share Posted April 1, 2013 wasn't it was KNO3/sulfur white? very nice shell btw, i'm having little problems with my 3". Link to comment Share on other sites More sharing options...
PyroCube Posted April 1, 2013 Author Share Posted April 1, 2013 Thank you, yes it was the simple white formula.I`m not quite happy with these stars, not all white cores ignited as you can see. Greets Link to comment Share on other sites More sharing options...
Oinikis Posted April 1, 2013 Share Posted April 1, 2013 well, i prime these with meal and they all ignite, everytime. maybe before rolling starcomp on these roll some meal. Link to comment Share on other sites More sharing options...
busspuppy Posted April 2, 2013 Share Posted April 2, 2013 Very nice. That was great. Nice lift and awesome burst. Link to comment Share on other sites More sharing options...
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