bombette star fuse

[dave321]

what would be a good pressed star type composition for the bottom of a bombette tube (to act as delay) ?

preferably non chlorate and easily ignited from bp lift

colour not necessarly important

i might add a small amount of resorcinol resin binder to improve "solidity".

 

any (sensible )ideas welcome

 

dave321

[TheSidewinder]

I moved your post to a more appropriate section. (Where it was before, is a section to post your own formulas.)

 

That said, you'd want to choose a formula that doesn't shrink or contract as it's drying.

 

A resorcinol glue would probably do the trick nicely, as long as you could be sure it has enough porosity to dry after its compacted into the cavity.

 

Is this a plastic bombette, or some type of paper?

[Mumbles]

Resorcinol doesn't need to "dry" traditionally by expelling solvent. Rather it cures, though I suppose there is a bit of methanol in there.

 

I've always been a fan of tailed compositions for these types of situations. Maybe try a glitter or something like Chysanthemum 6 or 8.

[Pyro09]

In my opinion, Chrysanthemum 8 works best! But D1 is also suitable, I've shot many bombettes with these two comps. Just make Crysanthemum/D1 with Red Gum instead of Dextrine and wet them lightly with acetone. Then you should press it, I never had any problems with shrinking.

[sutto]

Yes Chrysanthemum 8 works grate for bombettes also this comp isent a bad delay; Potassium nitrate 45 Charcoal 50 Dextrin 5 Edited February 2, 2010 by sutto

[Twotails]

I like useing a metal fuled willow, can be wetted with Acetone or Alcohol. The composition is as follows, it doesnt add to 100% becouse it needed tweeking, and i could probably clean it up a bit with further tests. its best primed with a slurry of BP or KP, then dipped wile still wet in granulated KP or BP(I dont think the priming is needed, but it adds to the fact that i know they will be lit by the lift)

 

I'll be making these in the next few days for inserts anyway, so i'll time a 1in delay, as it would be prepared for bombetts.

 

(it may be possable to substitute a diffrent wood charcoal, but i havent tested it yet)

Bamboo charcoal(airfloat) 34%

Potassium Perchlorate 30%

Potassium Nitrate 29%

Ferrotitanium, 40-325 mesh 25%

Sulfur 6%

Redgum 6%

3 micron Aluminum 5%

-325 mesh Atomized Aluminum 5%

 

Despite the amount of Kperch in it, its a slow to medium burnrate. The use of diffrent charcoals may speed the burnrate up.