Silverturk

What i have heard from the guys at APC's forum, the blackpowder should be pressed with about 6500 PSI. That's pound per scuare inch. 2 tons is about 4500 punds.

To find out the maximum diameter of a rocket: 4500 = R^2 x Pi x 6500
(4500/Pi6500)^1/2 = 0.468" ® Diameter ~ 0.94".
This means that you can press a 3lb rocket with that press.

I'm just using normal wooden glue, because it's easy to roll and becomes really hard. Yesterday i rolled a 1'' ID tube for launching a really small shell, and the wall thickness is about 3 mm, and it's so hard I can't even deform it with my fingers! No matter how hard i try. And my 1/2'' ID tubes for rockets has a wall thickness of 5 mm, and I can even stand on them without deforming it! The only thing I can do to deform the tube without using any tooling is to bite on the edge - they are then being bent a little. But the tube is getting back it's old shape as soon as I release pressure.

One thing makes me wonder;
Everybody here seem to paint the whole paper with glue before rolling. When i do this, the glue immediately soaks into the paper making it all full of wrinkles. The glue also stops being so stiffy as it used to be.
Instead, I put a thick string of glue across the paper (just as i start rolling the tube) just in front of the dowel. Then I push the dowel down as hard as I can and start rolling. All excess glue is then squesed in front of the dowel as I am rolling. A little glue is squesed out at the sides, but it's not much and it's easy to remove. Using this method takes a lot less glue compared with painting the whole paper in glue.

If you use "my method", remember to stop rolling and add more glue if it runs out at a small spot, ex. in the middle. If you just keep rolling untill all glue has been rolled in between the paper layers, you will end up with a hard tube that has a really thick wall which is full of air bubbels.

When I am making endburners, I'm making the hottest BP I can make - out of barbQ charcoal (even though I can make willow C, but thats a messy s**t), and re-chrystalizing the KNO3 using CIA. 75-15-10 ratio.

The wall-thickness of my rocket casing is about 4-4.5 mm. 12mm ID. Nozzle 3mm (works with 3.5mm, but has no thrust, and 2.5mm will just CATO.) I'm hand ramming my rockets. Remember not to ram all BP at the same time, fill it with 5ml meal powder and ram several times instead.

What i think you are doing wrong is that you are not ramming your end plugs hard enough. I ram my plugs 50 times really hard. Try that. And if your casing cracks, just make it thicker. Or use some sort of glue when you are rolling.

Or try this:
Use something like that BP I make (just use a slower charcoal) and fill your rockets with it. Make a couple of rockets. Then use 4mm nozzle, 4.5 mm, 5 mm etc. If your rocket becomes something like a fountain just after a nozzle size that CATO:ed, your rockets will never fly. Then your casing is too weak.
Ex: 5mm = CATO 5.5mm = Fountain