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12" can shell former wanted


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#1 Arthur

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Posted 12 May 2018 - 01:53 PM

I'm visiting NV CA and AZ on holiday to do some pyro and some tourist things in sept '18. I'd like the use of a former for a 12" cylinder shell. Is anyone able to advise on a retail item that's about the right size (10.5 to 11 inches diameter) and not too tapered please?



#2 NeighborJ

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Posted 12 May 2018 - 03:41 PM

Any good hardware store should carry round cement forms. They are thick, strong and inexpensive but not always the ideal diameter. For one or two shells it could be used by wrapping it with chipboard to the ideal diameter.
https://m.lowes.com/...-9-5-in/3018328

If you are shooting it at a club event there should be someone there able to bring one for you to use. In a pinch the OD of the next smaller size mortar tube is often a close match.

Edited by NeighborJ, 12 May 2018 - 03:42 PM.


#3 OldMarine

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Posted 15 May 2018 - 09:52 PM

Get a piece of 10" PVC and build it up with Ramboard. Then add a layer of foil tape to slick it up. Not my idea but I did it for my 5" former.


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#4 Mumbles

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Posted 15 May 2018 - 10:35 PM

You might not even need to build up schedule 40 10" PVC pipe.  It should have an OD of about 10.75", which is one of the standard sizes.  Depending on who you ask, a 12" former should either be 10.75" or 11".  

 

Another possibility is to make a bottom shot and build the shell on the casing.  When hand rolling them, you have a lot more flexibility in the ID of the bottom shot former since you can just do more turns on the casing.  Such a large shell would benefit from a solid support.  


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#5 CrossOut

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Posted Yesterday, 09:48 AM

Anyone have ideas for a  24" ball shell hemi former?  12"?



#6 Arthur

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Posted Yesterday, 02:45 PM

Big orange weather balloon inflated to size? Big orange met balloon inflated to size with expanding PU foam.

 

Look for ornamental concrete in garden fittings centres? Look for a lathe and cut a hemisphere from polystyrene or polyurethane foam from the insulation and spray foam markets. Do you have contacts with a 3D printer? even if you have to make segments?

 

Remember that a 12" shell is 11.5 to 11.75 inches diameter when finished so the inside diameter of the former is probably closer to 10" to 10.5" ID. The hemi needs to be robust then there is probably 1/4" + of paper tape wrapped over that. 

 

MY personal favourite method is to have a bottom hemi, then a ring and a lid. This means that you don't have to put two filled (and heavy!) parts together by hand. (You fuse then fill the bottom hemi then add the ring and fill that then fill the top and press the lid into place, all done with the bottom at the bottom, - less chance of spills!)



#7 chuckufarley

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Posted Yesterday, 02:49 PM

I would find an inflatable ball (Maybe one of the cheap ones at walmart?) You should be able to choose, then inflate to your desired diameter. Use that to make a fiberglass, or plaster...mold from.
Just my $.02

#8 NeighborJ

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Posted Yesterday, 08:23 PM

Buy one real one and fill one hemi with plaster. Peel,polyurethane and start wrapping.😊

#9 Maserface

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Posted Yesterday, 09:56 PM

Anyone have ideas for a  24" ball shell hemi former?  12"?


https://www.roguefit...ter-stone-molds

#10 NeighborJ

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Posted Today, 11:11 AM

Those look perfect Mase. I'm just thinking they would be a bit oversized for a mold.




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