1.5 Inch can shell

[Updup]

I have only made and launched 1 can shell, it worked great, so I wanted to make some more, because I used smaller stars for the next few shells I made, I put a center tube of thin paper (its masking paper) for the break and put the stars around that. I haven't launched the next ones I made yet, but thinking back on them, I may have made a mistake. Here is the shell setup The stars around the center break, I spiked this shell with thread.

 

Here are my thoughts, do you think the flame will pass thourgh the thin paper tube in the center to light the TT stars before the thread and paper shell breaks?

[dagabu]

I have only made and launched 1 can shell, it worked great, so I wanted to make some more, because I used smaller stars for the next few shells I made, I put a center tube of thin paper (its masking paper) for the break and put the stars around that. I haven't launched the next ones I made yet, but thinking back on them, I may have made a mistake. Here is the shell setup The stars around the center break, I spiked this shell with thread.

 

Here are my thoughts, do you think the flame will pass thourgh the thin paper tube in the center to light the TT stars before the thread and paper shell breaks?

 

Little egg on my face but I will give it a shot:

 

The shells look great, masking tape will let the fire pass... to most of the stars but a better choice may be tissue like the kind you put into gift bags. Without getting into an argument, the tube would be called a cannule (SP) but are usually removed as the powder is loaded into the shell. I use 20# copy paper, 1 turn, and leave it in the shell. I have had good luck with these. I use Na Benzo (whistle) for the break and spike with strapping tape. I also use visco wrapped with 1" of aluminum tape for the time fuse. It pops about 225' up.

 

D

[Bonny]

Personally, on shells that small I wouldn't bother with a cannule. Just fill the whole shell with stars and burst.

[firetech]

I fill my can shell completely with stars and fill in the extra space with bp hulls and whistle mix. Spiking helps but isn't necessary.

[Seymour]

Exactly, there is no way you can get a spherical chrysanthemum burst from a bombette, so you may as well just fill it with stars to get the maximum effect. Also, there is certainly no point using black powder on rice hulls, this thing is not large enough to warrant any filler, anywhere. Fill the gaps between the stars with fine grained BP, and then optionally add a booster.

 

Debating aside, I hope your shell goes well!

Edited November 4, 2009 by Seymour

[Updup]

Thanks guys. A few things though,

 

Dagabu, its not masking tape, its masking paper - basicly thin kraft paper - you can find a nice size roll for 2 bucks at your near by hardware store. And thanks for the tips .

 

Also, outside of the "cannule" i did fill the gaps with 20 mesh granulated black powder [=

 

the last shell i made (not the one i'm talking about), had only ten stars in it and it was not spiked at all. It went pretty high and broke on the way down i was so hyped after i lit this baby since it was my first shell

This is a video of my first star mine, i would have posted a video on my first shell but it was too large ]=

[dagabu]

Exactly, there is no way you can get a spherical chrysanthemum burst from a bombette, so you may as well just fill it with stars to get the maximum effect. Also, there is certainly no point using black powder on rice hulls, this thing is not large enough to warrant any filler, anywhere. Fill the gaps between the stars with fine grained BP, and then optionally add a booster.

 

Debating aside, I hope your shell goes well!

 

True, the cylinder will not look like a well made ball shell but for the size and ease of manufacture they are pretty nice. What I look for is a real hard break but don't want them to blow blind so whistle works the best for me.

 

I agree that the canuule is usually removed but when you consider what happens with little shells like these when handled may make you change your mind. A symmetrical break can be had in a well laid out shell even a 1.5" shell if you can keep them all on the wall and keep the break in the center.

 

I get all sorts of paper cores from work that are 1.5" Id that I use for testing stars. I cut them down to double their OD (around 3-1/8") and glue a homemade cap on one end, roll a 1/2" cannule from 20# copy paper, get a little hot glue on the end and glue it to the cap from the inside making sure it is centered. I then place one 3/8" star in the bottom of the cannule and drop cut stars in around the cannule until all of the space is taken just like the picture.

 

I then use a little scoop and fill the cannule with whistle powder, it's loose and fluffy and will settle to around 2/3 of its original displacement. I then take a 1" piece of old cake insert that is around 1/4" ID and glue it onto the inside of the top cap for a passfire. Then the top cap gets glued down to the cylinder and the whole shebang gets spiked with strapping tape top to bottom and all around.

 

If I remembered, I put a mark on the top cap so I could insert the time fuse which is just a 2" piece of Chinese visco wrapped with a 1" piece of aluminum tape. I take a scribe (ice pick) and make a hole in the center just smaller then the fuse and push it 2/4 the way in. I then hot gule the fuse on to the top cap to seal it from passfire.

 

The fuse is then primed with NC lacquer and Mil Spec 7 BP.

 

I like to top light them though lighting them from the burst cup works fine to. I don't try to put on a show or even have anyone around when I do this, the 2" mortar is pretty quiet and will pop the shell up around 200' for a good show but it is really all about seeing if all the stars light, how they burn and the duration of the burn.

 

They are by far my favorite header for rockets too but I usually just load the stars in 2/3 of the can and drop whistle in on top so the stars come out like a horse tail at apogee.

 

D

Edited November 4, 2009 by dagabu

[Updup]

Sounds like a good way of making them Dagabu, basicly the same thing I do but I use granulated bp in the cannule (thanks for that term i feel special now).

 

When I launch my next three or four 1.5 inch can shell I'll be sure and post the results here ;] I'm hoping for a semi symmetrical break [=.

 

I plan on letting them fly for new years, as it is only ~50 days away!

[dagabu]

Sounds like a good way of making them Dagabu, basicly the same thing I do but I use granulated bp in the cannule (thanks for that term i feel special now).

 

When I launch my next three or four 1.5 inch can shell I'll be sure and post the results here ;] I'm hoping for a semi symmetrical break [=.

 

I plan on letting them fly for new years, as it is only ~50 days away!

 

Dude, sorry, it's not cannule, its:

 

A cannula (from Latin "little reed"; plural cannulae) or canula.

 

I just had a Italian shell builder rip me a new one for calling it a cannule, asking me if I wanted a F*****G Espresso with my F*****G pastry?

 

I think that's cannoli but meh, what do I know

 

D

[TheSidewinder]

Yeah, that's a cannoli. Tasty.

 

Tell him he needs to get laid.

[Mumbles]

I often wondered about that thing. For a while I thought the actual powder train was called the cannule, while the tube used to form it was the cannula.

 

In the lab, when transferring liquids under inert atmosphere, you use a series of needles and air pressure. The needles are what are referred to as the cannula, for more obvious reasons. There is a similar medical terminology. Both examples show the tube itself being the cannula. I guess it is a tube of powder.

[Updup]

So its a cannula? Now I dont feel too smart =P