Zumber Posted March 18 Posted March 18 1-Mill bp outside in remote area away from people. 2- damp bp with little water and knead it well ,sieve it then mill it is needed to overcome heat generated by motion and friction between media jar etc. 3- always use non sparking media ( lead shots) for mill. 4- if possible avoide sulphur add it after milling process is done.
DavidF Posted March 18 Posted March 18 It is important to make sure the powder is very dry when ball milling, or the powder will clump in the (remotely located) mill.
Richtee Posted March 19 Posted March 19 12 hours ago, Zumber said: 1-Mill bp outside in remote area away from people. 2- damp bp with little water and knead it well ,sieve it then mill it is needed to overcome heat generated by motion and friction between media jar etc. 3- always use non sparking media ( lead shots) for mill. 4- if possible avoide sulphur add it after milling process is done. Naw... dry mill..all together for the best powder. Lead media, and outside if ya like, I do it in my basement. Argue if ya like.
greenlight Posted December 12 Posted December 12 What's peoples opinions on the safety of black powder that has been milled with lead balls such as fishing sinkers. There is obvious deformation of the spheres after many hours of milling. Does the resulting black powder contain enough traces of lead that it is a hazard to handle (dust-wise) or be exposed to the decomposition smoke upon burning over periods of time. Have always wondered about this and was interested as to what other opinions are.
cmjlab Posted December 12 Posted December 12 (edited) In my opinion, and I do love to opine since I'm not an expert in any of this...... I don't know much about toxicity of lead, or accumulative affects over time, but I can't imagine it being any worse than limited (hopefully) exposure to pyro comps containing Barium (toxic), Potassium Dichromate (carcinogen), copper salts (toxic), antimony trisulphide (toxic), lead based crackle, KCLO4 (allegedly ground contamination.... ), etc, etc. For the most part, I also don't use much pyro in close proximity. In fact the close proximity pyro folks are a whole different ballgame in order to control public exposure to bi-products from pyro effects. The little B.P. smoke I do inhale by accident, I hope doesn't count much towards the negative effects of accumulative lead exposure. Fingers crossed! 🙂 Chuck Edited December 12 by cmjlab
greenlight Posted December 14 Posted December 14 On 12/13/2024 at 7:46 AM, cmjlab said: In my opinion, and I do love to opine since I'm not an expert in any of this...... I don't know much about toxicity of lead, or accumulative affects over time, but I can't imagine it being any worse than limited (hopefully) exposure to pyro comps containing Barium (toxic), Potassium Dichromate (carcinogen), copper salts (toxic), antimony trisulphide (toxic), lead based crackle, KCLO4 (allegedly ground contamination.... ), etc, etc. For the most part, I also don't use much pyro in close proximity. In fact the close proximity pyro folks are a whole different ballgame in order to control public exposure to bi-products from pyro effects. The little B.P. smoke I do inhale by accident, I hope doesn't count much towards the negative effects of accumulative lead exposure. Fingers crossed! 🙂 Chuck Thankyou for offering a second opinion. I was questioning this because lead is an acute and chronic toxin which the body has difficulty removing once it is absorbed to the blood stream. Even though the lead media is elemental whereas the health concerns are due to soluble lead salts in compositions and their by-products. Black powder is used the most frequently out of all compositons when manufacturing pyrotechnic devices. I am guessing that the deformation of the media does not result in any introduction of fine particles and definitely no production of lead salts which are incorporated into the final produced BP but it would be interesting to mill a batch one day and then use an analytical method to detect lead (if any) in the final propellant.
Arthur Posted December 14 Posted December 14 There is NO real safe in pyro, just as in life. The only choice is to minimise the hazard and minimise the risk of it happening. What we think is best practise may change tomorrow, sometimes as a result of accidents. The Royal Gunpowder Mill (Waltham Abbey, England) made black powder by a wet, wheel mill process, with iron wheels weighing several tons which few of us can replicate. I've seen TV of a Spanish factory taking ultra fine ingredients and incorporating them into BP using wooden balls in wooden barrels. After milling pot nitrate with lead balls and ending with a grey mix of nitrate and lead powder, I prefer alumina media which is harder than lead.
Richtee Posted December 14 Posted December 14 1 hour ago, Arthur said: After milling pot nitrate with lead balls and ending with a grey mix of nitrate and lead powder, I prefer alumina media which is harder than lead. I'm digging my brass balls But I had used lead for years, and I’s still smart. 😵💫
Mumbles Posted December 17 Posted December 17 I'd be shocked if there were not at least minor contamination of lead into BP or other compositions over time. With extended use, you will definitely begin to notice the surface pitting a little and just become less smooth and shiny. If you mill something white, like just potassium nitrate, with lead it will also come out a shade of grey. This is part of the reason many prefer hardened lead. The contamination is probably still there, but minimized.
DavidF Posted December 19 Posted December 19 (edited) I'm a fan of screen-mixed BP, which I may have casually mentioned previously. A lot of my experiments with single component milling showed interesting results. When I milled charcoal by itself with hardened lead balls, the lead contamination in the charcoal could be measured in gram amounts! I forget the numbers though, but I used a Rebel 17 jar. Milling complete BP with the same setup had FAR less wear on the media. With just the charcoal, the media could just fall through it like it wasn't there, and clack against each other. When I milled charcoals with large cylindrical brass media, it was interesting to see how the different charcoals affected the color of the brass. With some charcoal, the brass looked almost white after milling, instead of the usual color. A quick general impression of media efficiency (tested with rocket motors and/or baseballs)- according to me only- is: Ceramic -OK Brass -Good Soft Lead -Same as brass Stainless Steel -Better, but not by much Hardened Lead -Best, but not by much These generalized results held true when milling just charcoal or when milling complete BP. The difference in efficiency between milling in a 4" diameter jar and a 6" jar is huge. In my (most likely unpopular;) opinion, the shape of milling jars in general use for milling BP and charcoal are not designed for milling efficiency, but for convenience. There are rock tumbler jars of the 'pancake' type that will do a much better job than the 'regular' shaped jars. If I was confined to using ceramic media, I'd want as much 'lift' as possible to help overcome the light weight of the media. I used to use the 'standard' PVC jars. They are OK if you want everybody within a half mile to know when the mill is running EDIT: Despite meticulous attempts to organize this post, the software had different ideas, lol. Edited December 19 by Mumbles Sort of fixed it for you
Recommended Posts