3 micron aluminum powder in bp

[dchambers490]

I am new to building small artillary shells and am having problems with getting a good burst. I use red gum bp for lift and burst. It works good for lift but poorly for burst. Would adding aluminum powder to the bp make the bp burn faster or just hotter. I am set up to make 1.75 inch shells. Does adding aluminum to bp increase the risks associated with using bp? Thanks for any help!

[OldMarine]

I would try to improve my BP before adding to it. Are you milling your powder? Details of your process would be helpful.

I've had bad results using red gum rather than dextrin for a binder. Using the same percentage the gum seems to slow down the burn rate more.

[dchambers490]

Don't have a ball mill but the red gum bp works great for lift. I use the skylighter recipe and their airfloat charcoal.

[OldMarine]

Yeah, I tried the Skylighter method at first too. I bought a cheapo Harbor Freight rock tumbler and Oh what a difference! Same KNO3, charcoal and sulfur but with dextrin and it was an entirely different animal.

You can try beefing up your current BP but I suspect you'll still be dissatisfied with it's performance.

[Merlin]

I been down the same road. What your using won't get it. Air float charcoal works for some things but makes poor BP. There is no other way to make good BP other than ball milling. It needs to be a mill that turns around 60 rpm and it must be at least half full of non sparking media - lead balls. Your Chems must be dry and milled sufficiently. You most accessible form of charcoal is likely willow which can be found online. The only other option is to make it yourself using easily obtainable red cedar pet bedding. There are many type of wood that can be used but I mention the easiest to obtain depending where you are. I also think white pine can work but have not tried it. The finished mill product (meal) should have 2-3% dextrin added and then just the right amount of water to make it somewhat feel like play dough. Not too wet. You should be able to squeeze it and it stick together but crumble when grated. Then granulate through a # 4 screen. Then it must be completely dried. Then you MUST pass it through 4, 12, 20 and 40 mesh screens to separate the grades into 2FA, 4FA, and 5 FA and smaller. And keep it dry.

This is just a response to your question. There are lots of discussion on BP in this forum and at passfire and fireworking.com. If you want to make shells the first thing to do is learn to make high grade BP. For shells the size you are making you likely need 5 FA for burst.

Another option for immediate gratification might be to purchase commercial BP in fffg for burst. You can get by with poorer BP for lift if you use enough but not for burst. I think I am advising you the right direction but you must read everything you can in the forum and other sources. Good BP is the foundation of fireworks and should be viewed as getting to first base. You can't get to a home run without getting to first base. That's my experience limited as it is.

[dchambers490]

Thanks for the help! I am reluctant to get a ball mill as it adds more risk but it's time to bite the bullet so to speak. Water is what activates dextrin vs alcohol? I hope I can get small shells right by next 4th of July. Some talk about whistle mix for small shells but again seems risky to make and store it. Do you think using willow charcoal and the redgum/ alcohol method would get better results for burst? Thanks again for any advice.

[dagabu]

Yes, alcohol does NOT activate dextrin, water does.

 

Ballmilling is inherently risky, if you dont have the room, dont do it! Buy your chems well ground and use the hot water with dextrin method using HOT charcoal, Eastern Red Cedar, Paulonia, Willow etc. Red gun and alcohol are expensive, the power increase is marginal.

 

There is nothing wrong with whistle mix or whistles in themselves, we are speaking to long core, powerful motors that are pressed with high pressures, NOT rammed! Whistles used for noise, inserts, spolettes etc dont show these same separation Cato issues.

[Merlin]

Thanks for the help! I am reluctant to get a ball mill as it adds more risk but it's time to bite the bullet so to speak. Water is what activates dextrin vs alcohol? I hope I can get small shells right by next 4th of July. Some talk about whistle mix for small shells but again seems risky to make and store it. Do you think using willow charcoal and the redgum/ alcohol method would get better results for burst? Thanks again for any advice.

[Merlin]

If you can't ball mill it is possible to make benzolift for small shells. Google it. I am not saying that's the way to go. For small shells like 1.75 purchasing fffg may be your best bet

[wyzard10]

Most home depots have a scrap bin where they sell warped and otherwise unusable wood. I raid it periodically and pull out the white pine 2x4's and use them to make charcoal it works pretty well for me. Just dont get it to knotty and its cheap enough that if you have to cut out a bad spot its no big deal.

[dagabu]

If you can't ball mill it is possible to make benzolift for small shells. Google it. I am not saying that's the way to go. For small shells like 1.75 purchasing fffg may be your best bet

 

I am not sure why you would want the added expense? Tests repeated ad nauseum show that simply well ground components combined with hot water and a HOT charcoal will make BP as strong as store bought. Which is another good question, where do you buy BP? ACE and Blackert are the only two places I know of. Pyrodex is not BP.

[Merlin]

Graf and sons. Gander Mt. Bass pro, Buffalo Arms and others.

Benzolift from green mix (BP not milled) will exceed the power of BP alone...

www.creagan.net fireworks compositions

Again I don't advocate that or buying BP just saying those are options. If you can get usable BP for burst for small shells from green mix then no doubt that would be the best from view of cost and safety.

[dchambers490]

Thanks for all of your input. I looked at alot of info this weekend and I like the benolift recipe you linked me to Merlin. Appears safe to make. I know it's another question but how about using slow flash? Any experience using slow flash as the bursting powder? Thanks again for the input!

[Mumbles]

Flash doesn't work very well as the only burst. It works best when augmenting something else, usually black powder or even something slower like polverone. Flash produces relatively little gas on it's own. I would not suggest trying to boost benzolift.

[pyroman2498]

Recently I'm seeing allot more commercial shells use flash for a boost i in my opinion i think flash ruins the shell effect if too much is used. At a recent show i went to help ,they were shooting dun pai ( i think that is how you spell it ) shells , and some of them had so much booster in was blinding when the shell burst, it was a huge flash with tiny color and it was displeasing.
So i would say use whistle or improve your BP.

The shells i build at the club the MCR's we had a while ago i think used Perc instead of Kno3 but i could be wrong.
The brakes we got on our 6" shells without any booster was AMAZING , such a hard brake for no booster, if you were there you would swear there was a booster in it!

Anyways ,

Stay Safe and Stay Green ,

~Steven

Edited July 11, 2016 by pyroman2498

[dchambers490]

From what I read benzolift is really hot! Perhaps hotter than slow flash. Appears to me Kno3 slow flash ( 50% pottasium nitrate, 30% Sulfer, and 20% Al powder) is safer than benzolift to deal with. I also think I will try to make my own charcoal out of weeping willow as there are lots of trees around here and use the redgum alcohol method as I already have those items. Do you think I will be disapointed with the results of that powder? Thanks for any advice!

[Sparx88]

I am new to building small artillary shells and am having problems with getting a good burst. I use red gum bp for lift and burst. It works good for lift but poorly for burst. Would adding aluminum powder to the bp make the bp burn faster or just hotter. I am set up to make 1.75 inch shells. Does adding aluminum to bp increase the risks associated with using bp? Thanks for any help!

 

Not by itself no. Any increase in perceived speed is due mostly to the increased heat.

 

The only thing you should be thinking about right now concerning quality BP is;

 

>>>>>>> "The Ballmill is King" <<<<<<<

[dchambers490]

I just don't have the room to safely ball mill at my current location so I am exploring all other options to come up with a alternative burst for my 1.75 inch canister shells. I have no experience with Benzolift or slow flash so that is what is generating my questions. I am looking for comments from others that have went that route. Thanks for the comments and the help.

[dagabu]

I just don't have the room to safely ball mill at my current location so I am exploring all other options to come up with a alternative burst for my 1.75 inch canister shells. I have no experience with Benzolift or slow flash so that is what is generating my questions. I am looking for comments from others that have went that route. Thanks for the comments and the help.

 

See below, it really does work, trust me.

 

 

I am not sure why you would want the added expense? Tests repeated ad nauseum show that simply well ground components combined with hot water and a HOT charcoal will make BP as strong as store bought. Which is another good question, where do you buy BP? ACE and Blackert are the only two places I know of. Pyrodex is not BP.

[Sparx88]

 

I am not sure why you would want the added expense? Tests repeated ad nauseum show that simply well ground components combined with hot water and a HOT charcoal will make BP as strong as store bought. Which is another good question, where do you buy BP? ACE and Blackert are the only two places I know of. Pyrodex is not BP.

 

He's right. This is how I made bp when I started and I started when I first became a member here. I learned everything pretty much from here. What Dag is talking about does work but I found that you'll need to granulate at least twice to get it good. Meaning you'll grind, mix, and wet with 80% water/20% alcohol with no binder then rice through a screen and let dry. Then re-grind that back up with the mortar/pestle add the dextrin 2-3% is enough, screen it to mix it in or add it before regrinding. Now wet it enough so it holds together in a ball but not so wet it squishes between your fingers and rice it to whatever size grains you need. Takes 24 hours or more to dry. Give it some airflow. I use paper plates to dry it on.

Now when wetting, you will boil the water or near boiling then just before you start adding it to the mix add the alcohol. This is optional. The use of alcohol just makes the water wetter and absorbs in faster and dries faster. Some opt to not use alcohol at all. But if you do use it, don't boil it

Edited July 13, 2016 by Sparx88