Revisiting the Maltesse Shell

[Bcorso85]

Thanks a lot. I will try my shell this weekend and see how it breaks. I'll go from there. Really appreciate the help everyone.

[marks265]

I am really confused on this thread. The title suggests Maltese shell construction but yet it doesn't seem like we are steering toward a Maltese shell.

 

Bcorso85, are you spiking the shell using Maltese spiking techniques and using the Maltese style of lifting the shell?

 

Mark

[Bcorso85]

Hey Mark. I'm not as famliar with Maltese shells as I am with round shells. During this conversation Maltese has referred to canister shells. I have spiked according to pyrotechnia IX and Ned gorskis recent spiking video on YouTube ( for visual support). I have posted a picture above.

 

As for lifting the shell, can you clarify? I have taken my pasted canister and ran quick match from the top of the shell, tied to the spolette, and down to the bottom with a baggie of b.p. I have used a baggie because I am using 10 grams to lift a 200 gram shell.

[psyco_1322]

The Maltese and Italians build cylinder shells very differently. The method for building and spiking the cases is different, the Italians use dry rolled casings, the Maltese use pasted "poster board" and craft, two turns of each, no matter the size of shell. The Maltese shell is not spiked with spaced out verticals and horizontals, it's completely covered in the spiking, by use of 1 ply jute twine. Then they are pasted with two turns of craft paper.

 

The lift is usually done with a slower powder, that is contained inside a spiked paper case. You could call this a maroon, basically a bp salute. Between this and the the shell is usually a thick wooden disk and wads of paper or cloth to make a sabot. The sabot helps seal the mortar off so the lift gasses are more useful, and cussion the shell against the maroons explosion.

[Bcorso85]

Then to be correct this thread is about the proper construction of an Italian style shell. I am using 8 ply cotton string, dry kraft paper, and the same number of layers per diameter of the shell for canister construction and pasting. My next shell will let me know if some poster board or additional layers of kraft needed to make them turn out well. I was very unaware of the diferences. Thanks pysco.

[marks265]

"During this conversation Maltese has referred to canister shells."

 

I wish people would not do this. You are not even close! For the shell you are shooting in an Italian style, the spiking is also Italian style, and the shell size also qualifies for Italian style more so than Maltese, I would use the style lift you describe. To title this thread as Maltese will really screw up searches for others is my point. I don't even want to explain Maltese lifting unless you are up a few more shell sizes. Shell sizes this small should never be associated with Maltese shells unless the word "insert" is used in my opinion. There is such a thing as a hybrid but I don't believe you picked up on anything to even qualify it as such either. I'm trying not to be mean but the verbiage is all wrong.

 

Mark

[Bcorso85]

That's why I joined to forum Mark.

[marks265]

As you build a few more you'll get a better idea of what's going on. Long with the wealth of info here and elsewhere, Pyrotechnia IX and XI should help a lot and doing a little experimenting with your own materials should not be completely left out. Some shells will look pretty good and others not so much! This is what makes the hobby interesting.

 

Mark

[Bcorso85]

Here's the shell guys. Tell me if I went wrong anywhere. Its my best yet. But I'm not 100% satisfied.

[Bcorso85]

[Bcorso85]

[JFeve81]

It looks good to me. What aren't you satisfied about?

[Bcorso85]

I was hoping for a more complete circle. The top of the break isn't equal to the other 3/4 of the shell.

[AirCowPeacock]

You won't get great symetrical breaks at first. You should be proud. In time you'll learn how to get a symetrical break, but don't worry about that just yet.

[dan999ification]

You will always find things you'd like to change even if everyone says its great.

 

Looks good to me, go easy on yourself

 

Dan.

[Bcorso85]

Thanks guys. I have a double break, but I'm not confident...even though if something went wrong with the break it would be sky high.

I think I'm going to dismantle them into two singles I know will be perfectly functional. Thanks for all the help guys. I'm sure I will have more questions in the future.

[AirCowPeacock]

Just shoot it. See how it goes.

[psyco_1322]

Yeah shoot it, not much can really go wrong.

 

For you first shell of this sort, it seemed pretty decent. I'll agree that it did have an empty spot on top, kind of looked like it broke coming down. If you broke it a bit harder, I think you would get a break more to your liking. Although things may change when you switch from newspaper casings to craft ones.

[Bcorso85]

This was b.p. broken. Is a 3 inch canister too big for slow flash? I have a little confusion on the subject and the formulas strength. For small canisters should it be perchlorate flake aluminum or nitrate dark aluminum?

[nater]

Cylinder shells, even small insert shells, are usually broken with granulated BP. I know some use a variety of boosters, but that really is dialed in to your liking. There's no right and wrong way, as long as you are happy with your results. Just remember that cylinder shells don't get perfect round breaks. A good break might look round to one person and look oblong to someone viewing the shells from a different orientation.

[psyco_1322]

If you granulated you own break bp, the stuff that should have been in the canulle. Make up some good 7:3, put an excess in some bp and tumble it around to get it well coated. Dump it into a screen and toss it around to get all the excess flash out. You should now have dusted bp, try this in you canulle next time and see how it works for you.

[Bcorso85]

Thanks psyco, i assume the standard perchlorate dark aluminum is too heavy. I will try a nitrate, dark aluminum/ sulfur mix. 50/25/25. Does anyone know if perchlorate fine flake aluminum would work better?

[psyco_1322]

Thanks psyco, i assume the standard perchlorate dark aluminum is too heavy. I will try a nitrate, dark aluminum/ sulfur mix. 50/25/25. Does anyone know if perchlorate fine flake aluminum would work better?

 

I was meaning a 7 parts perchlorate, 3 parts dark Al mix. I just checked last night, when dusting some chunky bp, and the dusting only adds 0.6% flash to the mix. It's hardly anything but it seems to bring up the pressure enough. The slow nitrate flash is more like a silver star comp, I doubt the slight dusting will do much using it.

[Mumbles]

Really 0.6%? That seems incredibly low. I use a mix of potassium nitrate, potassium perchlorate, and dark aluminum. With this, I add 6% by weight and most of it sticks. The aluminum I use is not black Al, but still a dark Al, like american dark. It's coarser than the flash only grades, about 325 mesh, and typically used in silver streamers and some flitter stars. The particular grade I use is Eckhart 10890.

[psyco_1322]

Yeah, started with 323g of bp, after dusting, it weighed 325g. Checked it again on another batch and came up with similar numbers. I toss it in a screen till there is not more dust falling off the granules. They are then light grey in color. Edited May 2, 2013 by psyco_1322