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Black Powder Thread #1


Givat

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I saw a post on Skylighter about using coins as milling media so I tried it out. I used like 40 nickles to mill some meal BP. I tumbled the comp for eight hours or more and was disappointed to find that the result was a poorley ground powder. I think you would have to fill your jar 1/2 full of coins to get a decently milled powder. I switched to 3/8" brass round stock cut to 1//2" lengths. Brass is expensive but works great and doesn't wear down appreciatively.
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I've almost finished my ball mill and got some media the other day and just rolled it round in the ball mill jar a bit and noticed that it leaves lines on the inside of the jar but you can't rub them off, does this mean the lead media is slowly wearing away?

 

This is the media http://www.trademe.co.nz/Browse/Listing.aspx?id=73598423

 

Is my optimum ball mill speed 92rpm if I have 105mm ID jar and 17.2mm OD media?

 

I also want to do this http://www.pyrotechniques.org/dwilliams/st...starroller.html

does it matter if its rolling at the same speed as the ball mill?

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Because you are using solid lead, the media is probably slowly wearing away. Thats why companies that sell milling media harden them with antimony. Lead is pretty soft, that's why they used it to write a long time ago. But the lead might contaminate whatever your milling so be careful.
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"But the lead might contaminate whatever your milling so be careful."

 

According to Los Alamos data, there is a dangerous incompatibility between lead powder and HMX. Just that you know... :P

 

Sorry couldn't resist! :D

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I've almost finished my ball mill and got some media the other day and just rolled it round in the ball mill jar a bit and noticed that it leaves lines on the inside of the jar but you can't rub them off, does this mean the lead media is slowly wearing away?

 

This is the media http://www.trademe.co.nz/Browse/Listing.aspx?id=73598423

 

Is my optimum ball mill speed 92rpm if I have 105mm ID jar and 17.2mm OD media?

 

I also want to do this http://www.pyrotechniques.org/dwilliams/st...starroller.html

does it matter if its rolling at the same speed as the ball mill?

When I first started milling BP I used lead tire weights for media. After milling a couple of batches of BP I noticed the media was getting worn down. The lead was soft and the friction was wearing it down. This could only mean that the lead was being added to the powder. The powder burned fine but obviously it had lead in it. The problem isn't lead contaminating the powder it's the lead contaminating you! Since the milled powder is so fine it is easily inhaled and will end up low in your respiratory tract. Lead is not good for you! If you use soft lead to mill powder please use a good dust mask or respirator to protect yourself from lead contamination. This is a basic safety precaution that should be used when handling any finely powdered chemicals. Also grain the powder to keep dust down when ramming rocket motors. I have since switched to brass media but ceramic media is available mail order.

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I have know idea where you found it but its totally wrong there is know way that would burn. Are you sure it didn’t say sodium chlorate?
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You better drop that idea right now, or you might just find yourself missing a finger or two. NEVER EVER mix chlorates and sulfur.
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Don’t make that comp, chlorates and sulphur don’t mix it can spontaneously ignite. You can make H3 though which is just a chlorate and charcoal.

 

Ah beat me to it PGF.

Edited by rocket
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yes you can,its used a weed killer :P

NaClO3 is not vey common except in france as a weed killer from what I have read. I am hoping you are saying that he might find it in a garden store because it is used as a weed killer, and not that you can mix NaClO3 and S because it is used as a weed killer...

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what is better round media or cylindersfor ball mill, because i will make my own media, and the best way is it to make cylinder. so????

 

 

 

LP,:D

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I've heard no difference. Cylinder is easier and more economical to cast though, and thus is the standard shape of home cast media. The difference is likely to be no more than half an hour in a properly charged optimized mill.
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  • 2 weeks later...

Good evening all.

 

 

I'm just inquiring as to where the 'ultimate' thead is?

If you have no idea what i'm talking about, it's the one with all the main popular topic threads including information on BP, Rockets, ball milling etc, listed in order of subject matter.

I tried searching but it led me nowhere (Even though that's how I came across it in the first place..).

 

 

 

The amount of information on this board pleases me...

 

 

Anyway, back to the topic of black powder. In your experience, what has performed best when using small paper rockets?

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I don't think there is an ultimate thread, we have a random thread.

 

What size rockets are you making? The 60% KNO3, 30% Charcoal, 10% Sulfur is pretty versitile

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I think he means the one like there was on the old forum in a sticky thread at the top of the newbie section that had all the topics sorted under different categories.(flash, fountains, etc...)
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i know from reading earlier in this black powder thread, i think it may have been around the 3rd or 4th page, it was mentioned that pressing and corning with a hydraulic press drastically increases the gas output/burn rate of black powder, but before i invest 170 or so dollars on a full set up with a guage and blast sheild, i would like to see a video of the two (granulated and corned) side by side, does anyone have a video like this or if its not to much trouble, film your own video, as i believe it would benifite not only me, but many of the forum members also.
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Hmm, I don't have a vido handy, but it makes a massive difference with my powder. Also a press can be used for pressing not only BP pucks, but also rockets, fountains, drivers, comets, crushing cans (WOW that is soo flat man!) press fitting bearings and such. They are a great tool.
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i know from reading earlier in this black powder thread, i think it may have been around the 3rd or 4th page, it was mentioned that pressing and corning with a hydraulic press drastically increases the gas output/burn rate of black powder, but before i invest 170 or so dollars on a full set up with a guage and blast sheild, i would like to see a video of the two (granulated and corned) side by side, does anyone have a video like this or if its not to much trouble, film your own video, as i believe it would benifite not only me, but many of the forum members also.

Not the greatest video, but here is a clip taken with my (silent) digital cam last year. 1gram of uncorned milled BP on the left, 1 gram of pressed and corned on the right.

 

http://www.apcforum.net/files/cornedBP1.wmv

 

The clip doesn't do the difference full justice, but you can see that the corned was a more energetic burn, from the pattern of the soot, etc.

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I did some testing a few years ago. It really does make a difference. Below is an old version of the page, but it still has all the info on it. It gave 48% longer hangtime.

 

http://mumble.freepgs.com/Pyro/BP.html

 

Some simple physics gives some average heights.

 

Corned: 6.9m

1.4: 11.8m

1.7: 14.8m

2.0: 12.2m

 

As you can see, properly pressed BP went roughly twice as high. The test wasn't perfect. There are a few things I would do differently now. Such as use the same grain sizes. At the first time I didn't have accurate enough screens. Also I would use a 3" plastic shell filled with clay. The test I did isn't as accurate for lifting of shells as much as it would be for say comets or small inserts. I would also use a commercial BP control.

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