titanium sponge

[insutama]

hey all i have been thinking of buying some titanium for my rockets to make a cool tail would titanium sponge work ? and what size does it have it be? thanks in advance

[FlaMtnBkr]

You can press titanium in the delay for a tail but you don't want to press it around the spindle because it will tear it up. Sponge will work but so will spherical and flake if it's the right size. I have never found sponge small enough to put in the delay but have used spherical and flake. They both worked fine and I'm not sure one is really better than another for that purpose. Maybe someone else has more of a preference.

 

I mainly use sponge in titanium salutes as the big "grape nut" size will easily light when that big and provides a long hang time.

 

For a rocket tail, I would think sponge in the 40-60 mesh size would be a good size. Maybe someone else has experience with it.

[GMetcalf]

Titanium in pretty much any form will give you the bushy white sparks I believe you're after. I believe sponge is the most expensive form of Titanium powder (at least it is round these here parts) but has a slightly higher surface area so burns brighter than granular but not as large a surface area as flake so burns a tad slower. The mesh size also has a massive part to play in the spark effect you get.

 

Here's a discussion on Titanium that might be of use:

http://www.amateurpyro.com/forums/topic/8202-titanium-sponge-vs-flakes/

 

Sponge is slightly rougher around the edges and is more likely to lead to ignition during ramming/pressing of a rocket motor though. To be on the safe side, I ram/press in Black Powder until I reach just over the spindle on my rocket tooling and then press the rest containing Titanium. As FlaMtnBkr says, this will also protect your spindle from being ripped into by the tough Titanium.

 

I use 60-100 mesh Titanium Sponge for all my fountains/rockets etc. and it produces a pretty good tail. No idea what the breakdown of sizes is though but it does produce quite dense bushy sparks so I'm guessing there's plenty of the finer material in there.

 

EDIT:

Also don't screen Titanium Sponge into compositions, it might be unsafe, I have no idea about that, but it'll certainly ruin your screen!

Edited June 8, 2015 by GMetcalf

[insutama]

i can only seem to find titanium sponge on ebay and basically thats the only place shipping to canada

[GMetcalf]

I also have a much easier time getting hold of sponge as compared to the other forms of Titanium, hence it's all I use now. As far as I'm aware though, there's no formula which specifically demands a particular form of Titanium (unlike when formulas contain Aluminium, where the form is very important). So you'll be fine with only sponge.

 

Out of interest; if anyone does know a formula which requires a particular form of Titanium and knows why then please do share!

[insutama]

is 0 - 2 mm a good size of sponge or is that too big ?

[GMetcalf]

That sounds rather large, a 2mm diameter particle would probably equate to about 6 mesh (depending on the thickness of the wire used to make the mesh). My Titanium Sponge feels and looks like fine sand.

[insutama]

ah okay thanks

i could probally mill it smaller i guess

[Mumbles]

Unlikely. Titanium is a very hard material, and will chew up most medias. I'm not entirely sure how they do it industrially, but it's likely via crushers and grinders. This probably still takes a toll on the machines. A blender you don't care much about, and a liquid to suspend it in might be your best bet. Don't forget about sizing screens you don't care much about to grade it.

[insutama]

very true