Lift charge problems

[KruseMissile]

The ignition device has a lot to do with speed. A blow torch blows the powder/granules around and makes it all ignite at once. wasd is using a grill ignitor where the granules only ignite from the surface on the side where the flame is. It still is a bit slow.

 

I suspect it is from the wood. Without really knowing what kind of wood it is, it's hard to tell. Softwoods generally give poorer BP than hardwoods. You may want to try to locate some known good wood, and cook your own. You don't need too much, just some sort of control. If your BP by any chance clumps in the mill, try stopping it every few hours and breaking it up to let it actually mill for the full time.

 

 

I thought softer woods are better, hence why pine, grapevine, balsa, and willow all work really well. I have tried Eucalyptus once and it sucked. It only worked for rocket fuel lol.

 

 

Harbor Freight mills are realiable for small batches, roughly 100g batches. Once you get past that, then it become too time consuming to continue to use it. To make them better and faster though, here is a video by Swervedriver.

http://www.youtube.com/user/Swervedriver71#p/u/17/Q5dMDblNH10

 

You can make linotype casted lead for cheap. All you need is....

linotype lead(tons of it on ebay)

3/4" copper pipe(for casting it)before casting though, lubricate it with WD-40 so when they are done the bars slip right out

aluminum foil tape(for closing one end of the pipe)

some sort of melting container

heat source

 

Once you pour the lead into the pipes, wait 30 mins and then put them in water to completely cool off. Then take a 3/4" or smaller dowel and push the bars out. Now you need to cut them. You can use a cut off bandsaw if you have one, otherwise I would just use a hand saw. GL

[dagabu]

Pogue,

 

Go ahead and buy the tumbler. It will take a lot longer to use this mill then a PVC 6" mill but it will work. Go to eBay for the real deal.

[dagabu]

Once you pour the lead into the pipes, wait 30 mins and then put them in water to completely cool off. Then take a 3/4" or smaller dowel and push the bars out. Now you need to cut them. You can use a cut off bandsaw if you have one, otherwise I would just use a hand saw. GL

 

One better, leave the lead in the pipe and press the lead into it nice and tight, dimple the outside with a center punch or just use a pipe cutter to make the lengths as it leaves a burr that will hold the lead in.

[jwitt]

@ pogue:

 

The mill linked on ebay is nice! I skipped a harbor freight mill because I immediately dove deep into pyro, but I'd still consider getting one for single-chem milling at home.

 

As to your question on how far a HF tumbler will get you as far as shell sizes-

 

I made a bunch of 3" ball shells this season, about 50 shells total I guess. BP production would be horribly freakin' time consuming with a HF tumbler and 100g batches of BP in 12-24 hours. The mill on ebay- 1kg batch of BP in 8 hours is a safe estimate. I haven't done any experimenting to optimize my mill/media/charge/time numbers, so I might be able to squeeze better powder and better mill efficiency if I'd tinker with mill charge (how much BP in a sesson). I'm no good at math, so I just chuck a kilo in the mill and let 'er rip until it forms a ball of mill dust. It should be noted that my BP isn't the best, so I should do some experimenting when I make powder for my next shells.

 

As far as star comps, they don't need to mill for long, and a 500g batch will do maybe 6-8 shells (rough estimate only). You can see how the numbers dictate your production potential.

 

So, it all boils down to what you want to do. If you want to make 3-4 shells at a time, 3" or 4" balls, you'd probably be happy with a HF tumbler. If you know you're sorta obsessive and you're going to build lots of shells, (know that you'll be able to make the time investment, safe estimate would be 3.5 hours per shell for stars, bp, burst, boost, fuse, building, pasting, finishing)........then you should plop down the money for the nice mill.

 

Also consider the safe operation and storage considerations- small is beautiful in that regard.

Edited August 6, 2010 by jwitt

[Mumbles]

This comes up every so often. There are softwoods, and there are soft woods. One word means that it an evergreen or conifer, doesn't lose it's leaves. Two words talks about the actual properties of the wood. Pine is a softwood and a soft wood. Willow is a hardwood and a soft wood. Oak is a hardwood and a hard wood. Clear as mud right?

 

In general hardwood, but soft wood varieties tend to make good BP. There are exceptions, such as some types of pine. Really, any charcoal can be made to work with enough work. I think part of it has to do with soft wood charcoal tends to be more friable due to the lower density.

[jwitt]

This comes up every so often. There are softwoods, and there are soft woods.

 

 

If I'm not mistaken, this has to do with the growing characteristics of the wood. Something like oak, a deciduous tree, is dense. That would be typically known as a Hardwood. As mentioned above, pine, a conifer, is what we'd commonly think of as a Softwood. Softwoods typically grow faster than Hardwoods.

 

 

Mahogany is a hardwood, like oak, and it is a HARD wood that will dull tools faster than most others. Tough stuff.

 

Poplar is a Hardwood, but if you've ever worked with it, it isn't much harder than pine. It's also really "fuzzy" while working. Willow is a Hardwood (I'm capitalizing these for a reason). I've never messed with willow wood, but I bet it isn't very hard stuff. I bet it's more like poplar than mahogany or oak.

 

Anyway, what I'm getting at is that I think the growing characteristics of a tree, combined with weather it's a "Hardwood" or "Softwood" (aka deciduous or coniferous) influence its pyrotechnic applications.

 

I bet mahogany would make lousy BP. We all know willow makes great BP. I bet willow is way less dense than mahogany or oak. I also bet willow grows faster than oak. (Mahogany isn't good to use in discussion of growth because it grows year-round down in Brazil and that area) I don't know how fast Red Alder grows, but the consensus is that it makes pretty nice BP, so I'll stick with my theory and bet that it grows quickly, relative to other Hardwoods.

 

Now, Softwoods sometimes make really pretty spark-generating charcoal for stars, but don't have enough..."potential energy" you could say...for the best BP production. This could be because it's an actual Softwood with different structure than Hardwoods, and the sparks might be from slight amounts of volatiles left in the charcoal after cooking?

 

I hope this makes sense. I feel like it's unorganized and I'm talking to hear my head rattle.

 

Edit: Wichita Buggy Whip article on charcoal tests: http://www.wichitabu...coal_tests.html

Edited August 6, 2010 by jwitt

[Algenco]

Relatively soft, fast growing, non-resinous wood are best

 

 

[pogue1000]

Is cedar any good? I am putting on my cedar deck today and will have some scraps.

[mabuse00]

Hi,

 

if the BP is to slow, why don't you just replace it for somthing like H3?

[jwitt]

Hi,

 

if the BP is to slow, why don't you just replace it for somthing like H3?

 

1) Because H3 is a chlorate burst composition, and (probably...don't know personally) not suitable for lift.

2) Because KNO3 is cheap, so the cost of making BP, even with investing in a mill, will quickly become cheaper than H3.

3) Because KClO3 is not something you want around your shop until you can safely deal with its incompatibilities.

4) Because H3 is probably (don't know for sure) more sensitive than BP.

[50AE]

H3 is too brutal to be used as lift. BP does a more gentle push. It's also more expensive. Edited August 16, 2010 by 50AE