Lift powder 4 inch shell

[Merlin]

You are probably saying why ask such a question? In my case I have tried and tried and tried to make a decent BP. Once or twice I managed a BP where 25g would lift a 3" shell only to have it not perform at all after a few months. I have made 1.75 to 3" shells and I have fine tuned them to lift and burst with benzolift. I want to make a few 4" shells for the 4th this year but from what I gather I cannot use benzolift to launch them because of different pressure and burn rates of benzolift vs BP.

My benzo is 70% whistle diluted with 30 BP% meal and granulated. Could I dilute the whistle to 50% with 50% meal and make it suitable to lift a 4" shell or just don't make 4" shells until I get decent BP? I know I am pathetic. Yes I use good charcoal -willow. I have tried water/dex and red gum/alc. I have adjusted the media ratio to BP mix in the milling. Nothing seems to work. The BP meal ignites and the granulated BP will go whoomph in a mortar but is weak- I think because it pulls in moisture so fast. I have had Goex on the shelf forever and works like new.

Edited May 21, 2015 by Merlin

[FlaMtnBkr]

Where did you get your chemicals? Did you make or buy your charcoal? Is it the only charcoal you have tried? What size and type is your milling media? Since you mentioned it, have you tried the mill jar half full of media and a quarter full of (only) chemicals? Milling time? Do you feel it is ever fast enough?

 

I know it's a bunch of questions but I would say get your BP figured out so you don't have to mess with whistle and benzolift. There must be something going on to be giving you issues with BP and hopefully we can figure out what.

[Merlin]

Where did you get your chemicals? Did you make or buy your charcoal? Is it the only charcoal you have tried? What size and type is your milling media? Since you mentioned it, have you tried the mill jar half full of media and a quarter full of (only) chemicals? Milling time? Do you feel it is ever fast enough?

 

I know it's a bunch of questions but I would say get your BP figured out so you don't have to mess with whistle and benzolift. There must be something going on to be giving you issues with BP and hopefully we can figure out what.

Chemicals- skylighter, thunder valley. I originally used skylighter airfloat with little success then I purchased willow lump from custom charcoal. I break it up with a sledge hammer then grind it to dust in a household blender. I have also taken that and milled it to airfloat in fineness. My milling media is .45 cal hard cast lead bullets ( I have tons). I do mill with the jar half full of lead and 1/4 full of chemical. I use a lortone 12 lb tumbler and let run 8 hours. I have let my small 6lb tumbler run 24 hours. The meal is very fine like air float. By fast enough are you referring to the tumbler or the finished BP. I cannot increase the rotation speed of the tumbler. As for finished BP. I did have a batch made with red gum and ethanol as a wetting agent that would send a baseball approx 600 feet with one ounce of lift. (12 sec flight -up and back) then when I used the same powder again a few months later- poof. I tried soaking the granules in acetone and re-drying to no effect. I must have made at least a dozen attempts. The meal-d I have on hand works for prime, BP rockets, and comets and benzolift but lacks power to lift shells to proper height.

I know the bullets were not round but they are somewhat rounded now due to use. Before I got the 12lb tumbler I used a 6lb tumbler. The 12 lb model has octogonal interior (roughly 2 inch flats) but the small one does not. I have even tried coating the granulated BP with graphite like Goex but it makes no difference. How Goex sets around for years and is unaffected in a metal can beats me. I have tried storing my BP in plastic ziplocks with desiccant. Frustrating beyond measure- hence the benzolift. Thanks

Edited May 21, 2015 by Merlin

[MrB]

How Goex sets around for years and is unaffected in a metal can beats me. I have tried storing my BP in plastic ziplocks with desiccant.

They mill it to the extreme, and then press slugs, break them up to make granulates, and coat them. It's pretty much a solid chunk, that is somewhat less likely to absorb moisture from the air. Storing your own stuff with a descant in a sealed bag, should have worked tho.

B!

[calebkessinger]

Store my stuff in paper bags, inside of 5 gallon buckets with gamma seal lids and desiccant.

 

my rice hulls seem to lift 4" shells fine even after a long time..

 

cedar chip bp..

[braddsn]

Merlin, something is amiss.. just not sure what. I store my bp in plastic containers indefinitely. Storage is not your problem I am betting. And the graphite, has nothing to do with it. Commercial companies use a graphite coating to make the powder less static sensitive. First, I assume you are using a ratio of 75 Nitrate, 15 charcoal, 10 sulfur yes? And 4% Dextrin. 8 hours should be more than enough time. 4 hours sounds more reasonable. How does the meal powder straight out of the mill burn? Make a small line of it about 5 inches long and light it. It should burn in half a second or so. In the past, whenever I have had performance problems with bp, ot has ALWAYS been due to moisture. Wasnt dry enough. Make 100% sure your powder is dry. How does it perform on rice hulls? Describe your granulating process please.

[Merlin]

Merlin, something is amiss.. just not sure what. I store my bp in plastic containers indefinitely. Storage is not your problem I am betting. And the graphite, has nothing to do with it. Commercial companies use a graphite coating to make the powder less static sensitive. First, I assume you are using a ratio of 75 Nitrate, 15 charcoal, 10 sulfur yes? And 4% Dextrin. 8 hours should be more than enough time. 4 hours sounds more reasonable. How does the meal powder straight out of the mill burn? Make a small line of it about 5 inches long and light it. It should burn in half a second or so. In the past, whenever I have had performance problems with bp, ot has ALWAYS been due to moisture. Wasnt dry enough. Make 100% sure your powder is dry. How does it perform on rice hulls? Describe your granulating process please.

 

Yes I do use 75 KNO3,15 willow, 10 S. I dry mill this. I then dissolve red gum in ethanol as a wetting/binding agent as I would for skylighters cut "rubber stars". I add enough to make a play-dough like consistency then force that through a 4 mesh screen. I have used a 6 mesh to get smaller granulation. Then I dry the granulation in a drying box using a ceramic heater to push the air through on a drying screen. I let this go until there is no odor of alcohol and it looks and feels dry. If I test it immediately it works reasonably well but after a few weeks it does not. The other method is the same except I use 5% dextrin and add distilled water to dampen the comp so that I can granulate as with the red gum/ alc method. Dry over night in drying box until it appears dry. I have also tried adding the dextrin to the milling comp but it seems to stick and clump up. Only did that once. It was a mess. I have not timed the dry meal-d but it does burn pretty quick. It only took once to learn to use visco fuse and not a grill lighter. I only used graphite once as it made no difference. The meal-d will work pretty good rammed in a rocket. As for rice hulls, I have never tried that I just weight the granulated BP into a lift cup or baggie.

 

Maybe I was wrong to try it but on one batch of bad granulated BP to make sure there was no water present I soaked it in acetone then dried as acetone will mix with water and evaporate quickly.

[Wiley]

Try this test:

https://m.youtube.com/watch?v=AJ8Jsud6eGo


It's just 3g of mill dust laid out in a line along the diagonal of a sheet of 8.5x11" paper. If it goes in under half a second, you have fast BP. Try that with your fresh mill dust, then store it however you do, and try the test again after 4 days, 1 week, and 2 weeks.

 

The mill dust in the video burns in about .4 seconds.

Edited May 22, 2015 by Wiley

[GMetcalf]

Well I used to have Black Powder problems and also resorted to using Benzolift. As the idea of having something which was 70% Whistle Mix lying around in a tub for a while didn't quite sit right with me, I made it 30% Whistle, 70% Black Powder. Didn't have any problems with exploding mortars and it lifted shells appropriately.

 

I agree with the others, this doesn't sound like a storage issue. It does sound like something is happening to your Black Powder over time though. How soon after grinding down your Charcoal do you mill your Black Powder? The most likely ingredient collecting moisture in the composition is usually the Charcoal, which can be up to 5-10% water. The finer the Charcoal, the more moisture it'll absorb from the air. Maybe try, as others have suggested, multiple other sources of Charcoal and see if you can improve the shelf life of your Black Powder that way.

 

Alternatively you could just use more Black Powder to lift your shells?

[braddsn]

Ok here is my suggestion. First remove the red gum. I know that some bp uses red gum as binder, but I also know red gum regulates burn. Mill your bp like normal with the dextrin included. Mill it for 4 hours. Its ok if it clumps.. makes no difference. Then take it out and test burn it. If you can video it. Make sure it performs well out of the mill, which I assume it will. Then granulate and let it dry for a LONG time. If there is ANY moisture in it, performance will suffer. Keep us posted. My guess is either red gum or moisture causing the problem. That is assuming your kno3 and charcoal is good.

[braddsn]

One more thing.. for the shells you are launching you should be using 4fa. Keep in mind.. bp can look and feel totally dry.. but there can be moisture inside. I let my 4fa dry for several days on kraft paper sitting on screen with a fan drying it.

[FlaMtnBkr]

I don't know because you have a good mill, media, and it sounds like you are doing things right.

 

The first thing I would do is to take some of your BP and put in a plastic bag. Put the sealed bag in the sun for an hour and make sure there is no water condensation. If there is, dry it all for longer and test again.

 

The second thing I would probably do is get new charcoal and try again. It probably wouldn't make a difference unless there is a major mix up or contaminant, but you might want to get some new nitrate, dextrin, and maybe even sulfur just so you know all the chems are good.

 

If it still doesn't work then look at your binding methods. But BP shouldn't be very hygroscopic and absorbing water in a sealed container. Leave the dessicant out unless you are sure it's bone dry as that could possibly be the source of moisture after drying initially. Though not likely but worth checking without knowing what the dessicant is and how saturated with water it is. Charcoal can absorb water but usually does so when not sealed and in high humidity. It acts like a sponge similar to molecular sieves and absorbs water when it's there but doesn't have a high affinity for it. So that probably isn't the issue.

 

*********

Edit: also, commercially made charcoal is usually made outdoors by the tons and buried under dirt to keep oxygen out while burning. It can sit outside and be rained on many times before being ground and packaged. This is why a lot of bought charcoal can have a good amount of water, not because it is very hygroscopic. Though it can absorb and hang onto it.

*********

 

So make sure it's dry and get some new charcoal and go from there. Didn't you join FPAG? If you can wait until 4F I can give you some new chemicals there to try, though the mighty 4th is well before that.

Edited May 22, 2015 by FlaMtnBkr

[Wiley]

One more thing.. for the shells you are launching you should be using 4fa. Keep in mind.. bp can look and feel totally dry.. but there can be moisture inside. I let my 4fa dry for several days on kraft paper sitting on screen with a fan drying it.

 

Brad, 5g of 2FA had no trouble lifting a 75g single break to proper display height. If your BP is genuinely good, the difference between 2FA and a finer powder should not be too huge.

 

Also, Brad, are you using 4% dex? I use 1% and get rock hard granules, FWIW.

[Merlin]

Thanks for all your help I have unopened boxes of Chem from various suppliers I can try. Maybe using too much water to granulate. I will try with dextrin and a very long drying, may have to use drying box as in Alabama it is quite humid. First I will do a timed burn test with some of my old meal. If that is good then I know I am not granulating correctly or drying long enough. Again thanks for all your suggestions!

By the way what is FPAG?

[FlaMtnBkr]

Guess not then :-)

 

It's the Florida Pyrotechnic Arts Guild. I thought I remembered you asking about it.

 

I use a lot of water to granulate. I add enough to where it is like modeling clay and glistening with water. As long as you dry it enough it's not an issue, though it does need to dry quickly or you will lose performance. I place on plastic trays in 1/4" layers and place in the sun. Every hour or so I stir it to bring damp material to the top. On a sunny day it should be dry in 2 or 3 hours which is what you want. Much longer and the nitrate crystals seem to grow and get bigger, slowing down the powder. At least that is what is thought to be happening.

 

I have had good BP take over night to dry due to weather and it wasn't very hot when dry. It does make a noticeable difference.

 

I just about always put some of what I'm drying in a plastic bag and place in the sun to make sure it's dry. If you see any water condensation it needs to dry longer. Some things that you are sure is dry will surprise you when placed in a bag out in the sun.

[GMetcalf]

I just about always put some of what I'm drying in a plastic bag and place in the sun to make sure it's dry. If you see any water condensation it needs to dry longer. Some things that you are sure is dry will surprise you when placed in a bag out in the sun.

 

This is actually a fantastic idea! I'm definitely going to start doing this with any stars etc. I make using water as the solvent to check if they're dry! Here in the UK the variable weather means drying things is a very inconsistent process so a neat trick to check if things are dry is very useful!

[enanthate]

Let it drty until it feels and looks dry, dry it some more, THEN give it a good round in your drying chamber.

 

My guess is that the moisture kills your BP during storage.

Something is messing it up during storage, and it cant be much else than moisture.

[Merlin]

Try this test:

 

https://m.youtube.com/watch?v=AJ8Jsud6eGo

 

 

It's just 3g of mill dust laid out in a line along the diagonal of a sheet of 8.5x11" paper. If it goes in under half a second, you have fast BP. Try that with your fresh mill dust, then store it however you do, and try the test again after 4 days, 1 week, and 2 weeks.

 

The mill dust in the video burns in about .4 seconds.

I got out six gallon bags I had since last year. Compared to yours mine is from very slow to medium -nothing like yours. Are you sure that isnt some kind of slow flash or whistle in your video? My cell phone is pretty shaky but here it is. I cant even simply weigh out 75-15-10 and grind it let alone granulate and dry.

Edited May 22, 2015 by Merlin

[Wiley]

The second video is more what you want for a repeatable test. A few notes though:

 

-Tape your fuse to the extreme corner of the sheet. You want to light the line from the very end; you don't want the fuse flying around and lighting the pile in the middle. The second video showed something like that happening.

 

-The second video looks like about .63 seconds burntime, but your fuse cheated and leapt into the line about 2" or so. See the first point on how to fix this.

 

-When you video, do like you did in the second video and get back far enough to see what's happening.

 

-I don't know if you did this, but weigh your powder. 3g is what I use. Keep everything the same between tests and you will have a fairly good idea of what your product is doing.

 

-A neat tool for finding burntimes and such is Avidemux video editor. Free, easy to use, and has this neat little counter in the bottom left, which, when you click through the video frame by frame, tells you exactly how long your stuff burned. Here's the linky: http://fixounet.free.fr/avidemux/

 

 

That is most definitely just BP made with western red cedar in my video, fresh from the mill. Slow flash is actually slower in the open air like this

 

Judging by the speed of your powder, my advice would be to mill it more. Do the test, but with an additional 2 hours and 4 hours of milling time and let us know how it goes.

Edited May 22, 2015 by Wiley

[Merlin]

I want to thank Wiley for putting me on to the burn test and the video editor to help time it. The problem is identified even though it is lurking somewhere in the twilight zone.

Ok I just weighed out a batch of 75/15/10, nitrate, willow charcoal, sulfur. The NO3 and S are pyro grade. The tumbler is half full of lead with 390 grams of comp. I am going to let it run all night until tomorrow afternoon. Makes me wonder if the lead is getting into the milled comp and affecting it in some unknown way. If that dont work I have to assume hot BP is just too difficult to make. I will take out 3 grams in the morning and run the burn rate on it and let it continue if not right.

In the mean time I made another batch of benzolift this time using double the amount of "fair" meal --the ratio being 70 meal/ 30 whistle instead of 70 whistle 30 meal. I even used benzoate rather than silicate as benzoate is supposedly slower. I fired 20 grams to lift a baseball in a 3 inch mortar and unfortunately it is still to powerful ( flight time up and back 11.3 sec). I know I could reduce the charge but the sound it makes tells me the shock wave is faster than BP. If my bp meal fails to produce satisfactory BP this time then I will try 90 meal to 10 whistle. I have no problem at all using benzolift for lift and break in 3" and smaller shells. But I am pretty sure the stuff I just fired might be too much too quick for a 4" shell.

I have to wonder if I am the only one having trouble with BP. Don't see much trouble posted by others...but for whatever reason it is definitely my basic milling process. This really does make me feel like a idiot after having spent 30 years not blowing myself up in a chem lab. Not a QC lab a chem lab.

 

P.S. I have tons of skylighter air float and had the same trouble. Hardwood air float is much of what is available. I kept reading willow charcoal was better so I purchased willow lump from custom charcoals. I do not know of another source for charcoal except to make it yourself and I am not set up for that. This is the reason I keep trying with the willow. I suspect however the charcoal is the most important of the 3 components.

Edited May 23, 2015 by Merlin

[calebkessinger]

I just got in some red alder charcoal I will be selling in small amounts. It is suppose to be just as fast as the cedar that a lot of people are using.

 

 

I need to mill a batch of bp with it first and test it to make sure it's as fast as people say it is. Then I will be ready to ship some.

 

No matter what I did I couldn't make acceptable bp out of skylighters charcoal either.. I have no trouble with the cedar chip stuff though. ( and I was overloading my mill )

[braddsn]

Wiley: you are correct, the difference in 2fa and 4fa is very minimal. I often lift 3 and 4 inchers with 2fa if I dont have any 4fa made. However, I am steering him to 4fa due to the fact that it dries quicker. I still suspect that moisture is his problem, and the smaller grains tend to help with that. Weather conditions have a lot to do with it too. The trick with the plastic bag in the sun is fool proof. That will tell the tale every time.

[FlaMtnBkr]

Charcoal is a huge factor and what I bet it ends up being. It is usually charcoal or the mill/media and you have the later covered and are doing everything right from the sounds of it.

 

I think custom charcoal is more a BBQ supplier and not pyro. It may be willow but he may have cooked the crap out of it, got it mixed up with some other hard wood, or something else.

 

But it is really easy to make charcoal. You can make a TLUD cooker with 2 paint cans and get a bale of pet bedding that is eastern red cedar from Wal-Mart and make some of the hottest charcoal around in 30 minutes. It's actually really easy, should cost less than $20, and takes a couple hours to do. Just something to think about.

 

But I'm willing to bet good charcoal does it for you. From your description of your process I'm about 90% sure it's the charcoal some how and that known good stuff will get you where you want to be.

 

IMHO. Good luck and you will get it figured out with some trial and error.

[Wiley]

Let us know how it goes. Don't give up on BP, it's too important a pyro product.

[Rocketier]

What is BP!?

 

KNO3 75, C 15 and S 10 mixed is ....... nothing actually.

 

KNO3, C and S milled will last green powder.

 

KNO3, C, S and max +2%dextrine milled moist and granulated results in pulverone. Nice to break small shells up to 3" or lift them. But is still not BP.

 

KNO3, C, S and max +2%dextrine (dextrine is not a must but I do it. Leaves a nice hard bp) milled moist and compressed and granulated results in BP. The compressed bp needs to have a density about 1,89gram/cm3. When you put this, after drying, in a small plastic bag under your shell. And put about 10 ricecorn in, it will stay dry till firing. The rice will absorb the moist out of the last air or compo in the liftbag.

 

For KNO3 I use HAIFA greenhouse grade.

S pyrograde from spain.
C I use is self made from willow branches and selfmade from Sequoia (this is red cedar) very hot bp. I also made C out of Straw. Using Straw C worked out to leave perfect quick burning pulverone. Did not made any bp with this.

 

 

The amount of lift I use with canisters is 8% to 10% of the shell weight. For ballshells I use up to 15% of the shell weight. When used in cakes sometime I dust the bpcorns with some apertura. 35KNO3, 35KCLO4, 30GD Al. Just to give it an extra umpf.........

Edited May 23, 2015 by Rocketier