53 replies to this topic

[adamw]

Just to add, PyroPlastics are no longer in business.

[Jerronimo]

Realy?

That sucks big time , haven't found them anywhere cheaper.
And Marcy was a very nice person to deal with.

[Richard H]

I'm afraid so, I heard it from Marcy on the PML.

[LadyKate]

Did you try this? I have a few left over from last year and I think I'll put something together and see whether it works.

Note: we were talking about using plastic Easter eggs as shell material

Wooo - hooo! That worked fine! The plastic was not brittle, in fact, it was fairly pliable. I used a whole egg (not two tops). I piped in fire with a soda straw (to the center of the shell), put a few BP rice hulls at the pointy end of the egg to make it a bit rounder, set it up with 1/4" stars on the outside, juiced it up with 1 gram of flash and the rest rice hulls and meal. Glued it with plastic glue (PVC cement didn't work). Stuck it on a rocket head and let 'er rip. It weighed in at about 100 grams - complete with rocket motor and stick. It had a very nice round break.

It should work as a mortar shell - the plastic seemed fairly durable.

I noticed the price was $1.50 a dozen for the eggs (about one British pound) which is not bad - I imagine they could be had cheaper the day after Easter. Unfortunately, there are none in my city right now - have to wait for Easter to scarf some more up.

EDIT: I was just scanning Best of AFN II and found the suggestion to use Easter Eggs. They were using them for 2" shells by wrapping them with tape and paper.

Edited by LadyKate, 25 July 2005 - 01:31 AM.

[karlfoxman]

Just want to add my shell hemis and method, my hemis are formed around a polystrene ball which is covered in plastic sheet to stop it sticking to the gummed kraft paper. Using strips of gummed kraft a build up 4 even layers that cover the entire ball. I punch a hole in the bottom (spoolette) and then using a pen and mesuring half way up i draw a line around the the shell. With a knife following the line i cut the shell in half and pull them off the mould, wait to dry and they end up being quite strong. Here is a picture with string loop and spoolette added.

Edited by karlfoxman, 31 July 2005 - 07:00 AM.

[LadyKate]

Just want to add my shell hemis and method, my hemis are formed around a polystrene ball which is covered in plastic sheet to stop it sticking to the gummed kraft paper. Using strips of gummed kraft a build up 4 even layers that cover the entire ball. I punch a hole in the bottom (spoolette) and then using a pen and mesuring half way up i draw a line around the the shell. With a knife following the line i cut the shell in half and pull them off the mould, wait to dry and they end up being quite strong. Here is a picture with string loop and spoolette added.

I do it about the same way - I let them dry a bit before I cut them. I also dry them inside a slightly modified food dehydrator - the first drying takes an hour and the second (finishing) takes about 30 minutes. I use newspaper dipped in diluted carpenter's glue instead of Kraft paper and I finish it with a coating of straight glue - rolled into the paper by hand (use latex gloves). A golf ball wrapped in cellophane (Saran wrap around here) and layered with four to six layers of newspaper makes a good 2" shell. Once I decide to make the mess of doing them, I make a dozen or more. However, and like others, I've found myself getting lazy and going to plastic shells more and more.



Here are a few ready to go to the dryer



Here is one split open and filled with ... uh.... dog food.



Here is an almost finished one - I put a layer of Kraft on the outside after I filled it. No label as yet, and it won't get a lift bag - I hate using all that fuse so I don't use lift bags very much. I drill a hole in the base of the mortar - if it is a paper tube I coat the hole with waterglass to stop it from eroding.

Edited by LadyKate, 31 July 2005 - 02:06 PM.

[karlfoxman]

They look good, i used to use the inside of a tennis ball to make small shells. I never used plastic hemis before, they must be so much easier and quicker. I dont think there are any suppliers in the UK for them so i might just stick to paper ones.

karl