stug161 Posted August 25, 2009 Posted August 25, 2009 My Super cheap Harbor Freight tumbler arrived today!! How Exciting!! I was getting around 55 RPM as it came. I gave the drive roller a few wraps of tape, and now it is right at 68 RPM. Not great but it will work for me. I have stainless .500 media. I am making a 125 gram batch of BP first. I took a 2 gram sample after five minutes, and at one hour I will take another. Then after 4 I will get some more, then after probably 8 hours I will take a final sample. I am going to set my samples up so I can test the speed back to back. Maybe a small poured strip and just eyeball speed test it. The tumbler does state not to go over 3Lb total per barrel. I am only using one barrel however. I figure speeding it up is hard enough on it. My media balls weigh 13.9 grams. My barrel weight 550, 125 BP, and quite a bit of media (only 40% full). I am thinking there is close to 100 balls. That is close to 5 LBS. Think I am pushing it too much? I guess I could try to get a slightly smaller, lighter barrel. Take 200 grams off the weight, and get a bit more speed. I think I hear some good milling going on, but with the rubber barrel, it is kinda hard to tell.. Thanks, Robert!!
Xtreme Pyro Posted August 25, 2009 Posted August 25, 2009 (edited) My Super cheap Harbor Freight tumbler arrived today!! How Exciting!! I was getting around 55 RPM as it came. I gave the drive roller a few wraps of tape, and now it is right at 68 RPM. Not great but it will work for me. I have stainless .500 media. I am making a 125 gram batch of BP first. I took a 2 gram sample after five minutes, and at one hour I will take another. Then after 4 I will get some more, then after probably 8 hours I will take a final sample. I am going to set my samples up so I can test the speed back to back. Maybe a small poured strip and just eyeball speed test it. The tumbler does state not to go over 3Lb total per barrel. I am only using one barrel however. I figure speeding it up is hard enough on it. My media balls weigh 13.9 grams. My barrel weight 550, 125 BP, and quite a bit of media (only 40% full). I am thinking there is close to 100 balls. That is close to 5 LBS. Think I am pushing it too much? I guess I could try to get a slightly smaller, lighter barrel. Take 200 grams off the weight, and get a bit more speed. I think I hear some good milling going on, but with the rubber barrel, it is kinda hard to tell.. Thanks, Robert!! Congrats on obtaining your new tumbler, im sure you will soon be on your way to success . I use the same tumbler and managed to get it up to about 85 RPM by wrapping the rollers with alot of electrical tape. It make's great lift powder, even 68 RPM should make good quality powder for all your needs. For media in mine i use 100 .490" lead media. Oh and by the way your probrably going to need to use that extra belt that comes with it soon enough mine lasted me about a week, if I were you I would order the urethane belt from pyrocreations it would last you ALOT longer. http://www.pyrocreations.com/inc/sdetail/22589 Edited August 25, 2009 by Xtreme Pyro
Twotails Posted August 25, 2009 Posted August 25, 2009 I orderd the 3lb mill from cannon fuse ( i dident know the harbor freight was the same exact model). so i ended up spending $63.... thats incuding shipping. Im using 25 .570 lead balls. (58 cal. rifle balls), 50 balls for $7.55+Tax(6.25%), I got two sets (100 balls). seemes to be running at around 60-70RPM, without tape. I have a 100g batch+ 30-50g black powder i had already made. its been running for about four hours, and is already as fast as my hand made BP. Its nice and quiet. I might reduce the amount of BP by half tomorrow, and give it another cycle. but so far it meets, or exeeds my expectations. each ball in the machine weighs .66oz, so i have 16.5oz of media in the mill, seems adiquite enough. im going back to get some smaller balls, and the guy just called, he said if i plan on buying more, he'll throw in some odds and ends ( he said he has some hardened lead "coins" mesuring the size of a quarter, and four times its thickness. he found them in the back room, and said if i want them i can have them, he said he must have alteast 25lbs of disks, most good condition, some bent/snaped/warped. i'll just melt those down if theres alot of broken ones.) im not sure if the flatness of them would work, but who knows.....
Mumbles Posted August 25, 2009 Posted August 25, 2009 Put some more media in there twotails. At least 100 of that size. I use approximately that many, but it's still undercharged at takes 8-12 hours. Don't worry about the weight capacity, I consider it more of a suggestion, or the quantity of rock it will hold.
Swede Posted August 25, 2009 Posted August 25, 2009 These rock tumblers make BP just fine... it's a bit slower, is all. When the belt breaks (which it always seems to do in a matter of days) replace it with a big o-ring from a plumbing or pool store. May I suggest those that are using soft lead media, like the rifle balls, watch out for the lead content in the BP? Soft lead really erodes at a phenominal rate. If you have a good scale, measure 10 of the balls before and after a mill job, and you might find that significant amounts of lead are being intimately ground into the BP. I remember (in my case) it was a few grams per kilo of BP. Thats a lot of lead. The smoke cannot be very healthy, especially when you think about all the appreciative sniffing that goes on during a show!
Twotails Posted August 25, 2009 Posted August 25, 2009 (edited) Well i've been milling my BP for, oh 15 hours or so, with the small amount of media. Im gonna go test it, and maby add more media. EDIT: Just tested a little bit of the BP from my mill ( when i opened up the drum it was stuck to the back and sides) Its was like, the most potent BP i have ever made, it acted just like FP. I weighed my lead balls, and the weight before the 15 hours of milling was .66oz each ball, after the milling, they weighed .64oz, thats .02oz x 25 balls, so its roughly 0.50oz of lead in the BP. I will definitly look and see if he has any Lead-antimony balls/sinkers next time. Edited August 26, 2009 by Twotails
Mumbles Posted August 26, 2009 Posted August 26, 2009 I'd weigh it over a series of millings, and weigh all the balls at once. Those scales arn't accurate enough to be trying to make a decision off of only 1 ball.
Twotails Posted August 27, 2009 Posted August 27, 2009 I'd weigh it over a series of millings, and weigh all the balls at once. Those scales arn't accurate enough to be trying to make a decision off of only 1 ball. I weighed each of the 25 balls, and all but few were .66oz each ( four were .65oz) After milling, and after washing the balls, they lost roughly .02oz each ( a few lost a little more, or a little less, but it evened out) so a question, now that there is roughly .50oz of lead in this batch, Is it somthing to worry about? I mean, lead is toxic, and i dont plan on inhaling the smoke, or touching the BP without gloves. Is there too much lead in my BP?( i just made some Chinise Firecraker fuse with a little bit, just a six inch peice, but it burned roughly .5s per inch, it was still slightly damp( diped the fuse in thin NC) i dont think thats too bad do you? the fuse thickness was 1mm or less(?).)
TheSidewinder Posted August 27, 2009 Posted August 27, 2009 Yes, a half-ounce of lead really is "too much". You may not be inhaling it but that lead ends up settling on whatever is downwind of your shell, unburned and a nasty pollutant. Admittedly, compared to the total pollutants out there it's minuscule. But it's still a bad thing.
Swede Posted August 27, 2009 Posted August 27, 2009 I think so too. I'm less of a wheeny than I might seem when it comes to toxicity - I don't mind working with potentially toxic chemicals, but ones that accumulate bother me, and most heavy metals do accumulate. When you think about kids and stuff, too... their bodies are much more susceptible than adults when it comes to lead, mercury, cadmium, etc. And kids love watching (and being close to) fireworks. All is not lost. Use the BP as needed. But I wouldn't make a career of using soft lead as a media. Try washing the balls (maybe even boiling them), then melting them down and adding tin, which can be bought as pure ingots. Recast them into media shapes. There are a few threads here devoted to this procedure. I have never measured the erosion rate of hardened lead, but it is supposed to be much, much less.
Arthur Posted August 28, 2009 Posted August 28, 2009 Check the alloy used in your country for wheel balancing weights at a tyre shop. Some are harder antimony lead alloy and make longer lasting ball mill media. Just melt them and the steel hooks float out! Other metals are used also now Bismuth I think to reduce toxicity.
Mumbles Posted August 28, 2009 Posted August 28, 2009 In the US, they're switching to steel. I'm a fan of linotype lead. You can cut it in half with soft lead, and still end up with quite hard media. You can probably go 2/3 soft lead actually. Linotype contains 4% tin, and 12% antimony.
Twotails Posted August 30, 2009 Posted August 30, 2009 Im trying to find a supply of bismuth, I was recently at a Museum and saw that they have bismuth for sale(as medium sized art peices) I asked to see someone in charge, and asked if they break every now and then, and he said they do, I asked his what is done with the broken bismuth, and he said normaly its shipped back to the supplyer. I told him i was looking for bismith, and asked if i could buy the broken bismith. He said he'd be happy to sell it to me the next time some broke. ( 1/2 off the price too!)Although, I dont think they break often. Anyone know where i might be able to find bismuth cheap/reasonable?
Swede Posted August 31, 2009 Posted August 31, 2009 Im trying to find a supply of bismuth, I was recently at a Museum and saw that they have bismuth for sale(as medium sized art peices) I asked to see someone in charge, and asked if they break every now and then, and he said they do, I asked his what is done with the broken bismuth, and he said normaly its shipped back to the supplyer. I told him i was looking for bismith, and asked if i could buy the broken bismith. He said he'd be happy to sell it to me the next time some broke. ( 1/2 off the price too!)Although, I dont think they break often. Anyone know where i might be able to find bismuth cheap/reasonable? Bismuth is expensive, but it'd be a great media, I think. Probably the easiest source is going to be Bi round shot, which is sometimes used as a replacement for lead shot in waterfowl hunting. The problem is, it'll probably be too small, but MAYBE some heavy goose shot extracted from bismuth shotshells might work, or ordered directly from a reloading company. Just a thought. I think even buck shot would be too small for effective ball milling.
Twotails Posted September 4, 2009 Posted September 4, 2009 well, bismuth melts at (i think under) 600F, and i shold be able to cast it like lead. Im wondering, would a alloy of Lead/Bismith work? or Lead/Bismith/Tin(or antimony). Hmm, i'll have to do some reaserch.
Recommended Posts