tradami Posted March 29, 2015 Posted March 29, 2015 (edited) So I just tested out my first 3" shells. I'm trying to figure out what I did wrong. I used just over 12% lift in both shells. Two different batches of BP. The ball shell was made with BP granulated through a 20 mesh screen. The canister shell was made with BP granulated through a 4 mesh then put on a 12 mesh to make 2FA. Both shells fit snugly in the tube. Did I not dry my BP fast enough? Is it because I use well water to granulate? Both BP batches were made with the following formua:75% KNO315% charcoal10% sulfur5% dextrin The first batch of 20 mesh BP was made with airfloat charcoal bought online about 4 years ago and stored in a container.The second batch of BP which was used for the can lift was made with airfloat charcoal bought less than a month ago.Both were milled for at least 8 hours. Can weighed 263 grams and I used 30 grams of BP for lift. 2FA BP:http://oi62.tinypic.com/2nrps1u.jpgBP burn test 2FA(Can): https://www.youtube.com/watch?v=h88veIHX3UM 3" Ball:https://www.youtube.com/watch?v=fcGOO9iKZvg 3" Can:https://www.youtube.com/watch?v=yF9pOajsFnA Edited March 29, 2015 by tradami
clarkie752 Posted March 29, 2015 Posted March 29, 2015 what type of ball mill did you use to make it? and how was it loaded? it should be half full of media and 1/4 full with chemicals. what is your rpm on your mill? The powder looked slow like my hand mixed bp does.
calebkessinger Posted March 29, 2015 Posted March 29, 2015 Those were wonderful looking stars !! Slow bp is a normal problem to have starting out.. I would venture to say it is from the commercial charcoal. search for how to cook your own charcoal, tlud method or retort. get some cedar pet bedding and cook some up... try again... I would bet 20 bucks you will be happy with the results. ! There is a lot of other things that could be wrong but the charcoal is most likely in my opinion. 1
tradami Posted March 29, 2015 Author Posted March 29, 2015 what type of ball mill did you use to make it? and how was it loaded? it should be half full of media and 1/4 full with chemicals. what is your rpm on your mill? The powder looked slow like my hand mixed bp does.I'm currently using a HF 3lb rock tumbler with 100 50 cal lead shot in it. I mill around 130 grams of BP at a time with it and my mill is half empty. The BP I milled for the can lift was milled for 10 hours. One thing I did notice though was that due to the cold temps my rubber jar wasn't gripping the drive very well and so it wasn't spinning like it should be. I'm thinking that might be it. Should I dump the granules back in the mill and let it mill or consider the BP a lost cause? My mill is not modified so it spins at default RPMs. Those were wonderful looking stars !! Slow bp is a normal problem to have starting out.. I would venture to say it is from the commercial charcoal. search for how to cook your own charcoal, tlud method or retort. get some cedar pet bedding and cook some up... try again... I would bet 20 bucks you will be happy with the results. ! There is a lot of other things that could be wrong but the charcoal is most likely in my opinion. Thanks! They were my first successful rolled stars. I really wish I could have seen them 300 ft up though lol. I've thought about making my own charcoal and I know its better but I feel as though this shouldn't be this bad even with this charcoal. I mean skylighter shows 26 grams getting a baseball 6.5 seconds air time. My can barely made it out of the tube.
clarkie752 Posted March 29, 2015 Posted March 29, 2015 I have made bp with skylighters airfloat and yeah it wasnt super fast but i could lift a baseball 300 ft no problem. The amount of chemicals you are trying to mill is not the problem, i mill 126 grams in my 6 pound mill. You may not have enough media in your mill. when your jar is empty, make sure your media is taking up half of the mill jar. i think the combination of the mill not turning at the right rpms and the media charge being to low is why your bp did not turn out. I would get a hold of caleb kessinger and buy 5 pounds of his hardened lead media for your mill. that will fill it half way up and even with the slower rpms i think you would get useable bp if your running the mill for 8 to 10 hours at a time, as long as the motor holds up on the 3 pound mill. My 6 pound mill runs at 86 rpm and i only mill my powder for 4 hours at a time. good luck and stay safe. 1
clarkie752 Posted March 29, 2015 Posted March 29, 2015 I also agree with caleb those stars looked very nice and had good ignition.
db5086 Posted March 29, 2015 Posted March 29, 2015 Get your hands on a quality charcoal and you will be amazed at the difference. My preference is Willow since it's readily available in my area. Commercial affiliate has never performed for me.
tradami Posted March 29, 2015 Author Posted March 29, 2015 So I was definitely lacking in media. I dont know what I was thinking. I only had 100 .50 lead shot in it. I just added 200 .44 cal lead media to my mill. It's milling now. Once I can get to home depot I'll pick up some tubing to increase the RPM. It's a nice windy 40ish degree day outside so the motor should be getting plenty of air. We'll see how it performs. Hopefully I wont need to upgrade to the 6lb mill but we'll see.
Mumbles Posted March 29, 2015 Posted March 29, 2015 The 3lb and 6lb models both have the exact same motor. Most people seem to be unaware of or actively ignore this fact.
db5086 Posted March 29, 2015 Posted March 29, 2015 Tradami, commercial airfloat has its place but lifting shells is not one of them. I have walked the same path that your on so save yourself the frustration. The difference between charcoals is profound. Check your email.
tradami Posted March 29, 2015 Author Posted March 29, 2015 The 3lb and 6lb models both have the exact same motor. Most people seem to be unaware of or actively ignore this fact. Thanks. I was in fact unaware. Good info to have!
Arthur Posted March 29, 2015 Posted March 29, 2015 (edited) The most dramatic effect with BP is the origin of the charcoal. Willow, Alder and Pawlonia are good woods to start with lots of others just don't work. If you see the charred wood it should break easily and just crumble in the hand, if it doesn't it's never going to make good BP. Poor BP will eventually burst the ball casing (eventually in terms of milliseconds) BUT poor BP will burn in the mortar just like a fountain and the shell will not lift. Added;The other issue is the shell timing fuse. If the shell timing fuse is short then even a full lift shell will break low Edited March 29, 2015 by Arthur
Arthur Posted March 29, 2015 Posted March 29, 2015 Also those stars look big to me, are they a size that you've made into previous 3" shells. 1
tradami Posted March 29, 2015 Author Posted March 29, 2015 (edited) The most dramatic effect with BP is the origin of the charcoal. Willow, Alder and Pawlonia are good woods to start with lots of others just don't work. If you see the charred wood it should break easily and just crumble in the hand, if it doesn't it's never going to make good BP. Poor BP will eventually burst the ball casing (eventually in terms of milliseconds) BUT poor BP will burn in the mortar just like a fountain and the shell will not lift. Added;The other issue is the shell timing fuse. If the shell timing fuse is short then even a full lift shell will break low The time fuse was my first concern but I was happy to find out that my actual issue was just the lift. Also those stars look big to me, are they a size that you've made into previous 3" shells. This was my first 3" shell with rolled stars. You can find the info on the stars in this thread. I used stars in size less than 5/8" but greater than 3/8".http://www.amateurpyro.com/forums/topic/10672-more-uniform-star-rolling/ Edited March 29, 2015 by tradami
clarkie752 Posted March 29, 2015 Posted March 29, 2015 The 3lb and 6lb models both have the exact same motor. Most people seem to be unaware of or actively ignore this fact. i was unaware that the motor was different. Thanks for pointing that out.i meant to say the same. Sorry i just woke up lol
tradami Posted March 29, 2015 Author Posted March 29, 2015 Adding the additional media put my jar at 7 lbs. with about 6.2lbs of media . I reduced the media to 5 lbs.
Mumbles Posted March 29, 2015 Posted March 29, 2015 Also, for note. The poundage rating on a rock tumber, is a general capacity of rocks. It has nothing to do with the strength of the motor, or maximum weight capacity. It's very common for properly loaded jars to comfortably double the poundage rating for a mill.
coogan1997 Posted March 29, 2015 Posted March 29, 2015 so I could probably run a hf 6lb mill with both barrels full of media, which would be about 10lbs?
pex Posted March 29, 2015 Posted March 29, 2015 I have that question to? Can you runn both jars ar your mill with lead media.
db5086 Posted March 30, 2015 Posted March 30, 2015 I tried running both jars but did not have any luck so I just run the one. 3/8ths full of lead, three different sizes and 200g bp green. 6 to 8 hrs or until the ball forms (still get a kick out of that). This works for me. I don't granulate the mp until I have a couple+ lbs and I'm certain it will dry promptly. My bp is every bit as good as Goex if not better. As I mentioned and others have mentioned, the secret is with the charcoal. I've no experience with ERC since I have pretty much all the willow I want and I have gotten my shells up to where they belong using the 10% ratio. This did not happen overnight, and would not have happened without this forum. There is a wealth of experience here and some super knowledgeable pyros that share it without prejudice. Best of luck on getting both jars going I just felt it was too much for that little motor.
DaMounty Posted March 30, 2015 Posted March 30, 2015 Has anyone else come across this article on BP? http://pyrotechnic.narod.ru/Black_Powder.pdf Not a bad read. DaM
tradami Posted March 30, 2015 Author Posted March 30, 2015 Has anyone else come across this article on BP? http://pyrotechnic.narod.ru/Black_Powder.pdf Not a bad read. DaM 404 error.
DaMounty Posted March 30, 2015 Posted March 30, 2015 Try this one http://www.pyrotechnic.narod.ru/Black_Powder.pdf DaM
tradami Posted March 30, 2015 Author Posted March 30, 2015 Try this one http://www.pyrotechnic.narod.ru/Black_Powder.pdf DaM Thanks for that link! I looked it over and it has a lot of good info!
Mumbles Posted March 30, 2015 Posted March 30, 2015 Maybe I should have thought before my last post. The 3lb mill comfortably handles a 6 or 7lb jar. Since the 3lb and 6lb mills have the same motor, the 6lb mill will also handle this amount. It might not handle 12lbs though. Seems the possible major exception is the case we're currently talking about. I had to give my old 3lb mill a hand start, but the rolling area is smaller and I assumed friction was holding it up initially.
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