hondo Posted January 30, 2009 Posted January 30, 2009 I have been ball milling my bp for a year now, and lately my powder is clumping up in the mill, it use to come out nice and fluffy. Whats happening, is the potassium nitrate or sulfur absorbing moisture and causing the clumping problem
andyboy Posted January 30, 2009 Posted January 30, 2009 (edited) Do you really need to ball-mill it for a year? Usually both the charcoal and the nitrate will absorb moisture. If you ball-mill it long enough it will start to bind even without moisture because of the fine particle size. Edit: Clarifying. Edited January 30, 2009 by andyboy
tentacles Posted January 31, 2009 Posted January 31, 2009 (edited) I'd suspect that both your KNO3 and charcoal have absorbed some moisture, bake em in an oven at 225F for a while (long enough to heat up, at least) and then try milling them, once they've cooled down. Also, it can be a function of temperature, Ned Gorski has reported that this always tends to happen if the mill/jar is in a hot environment, the sulfur gets sticky and it balls up. Edited January 31, 2009 by tentacles
swervedriver Posted February 2, 2009 Posted February 2, 2009 I've experienced this too. I've run the gamut with it, from getting one huge boulder of bp, to having each individual lead media coated in a hard layer of bp with no dust at all left in the mill. I'd have to add water and remill it, then dry the dough. A real pain too. After thinking it was my kno3, and much frustration of trying to keep it dry, the whole time it was the sulfur i was using. Not sure why, but the sulfur was the culprit in my case. Now I use rubbermaker's sulfur and the problem is gone. The more I milled it, the worse it got...
kinglerock Posted February 3, 2009 Posted February 3, 2009 hi im just about to buy a ball mill and was wondering will this do if i buy a lead media (i hear thats the best for the job) and if so what size of media would i buy with it? http://www.manchesterminerals.co.uk/acatalog/10-006a.jpg<h3 class="product">TUMBLER 900gm BEACH +BARREL(for stone)</h3>Ref: 10-006 TUMBLING MACHINE.This is a low cost and popular introduction to pebble-polishing for people of any age and it is supplied with a 900gm capacity barrel and full instructions.If spare barrels are required see Ref 10-011 in this section (or 10-012 for vaned barrel to use with metal)This is a good value machine, ideal for beginners or those requiring only a small output from their machine. Not as versatile as the twin barrel units but still capable of doing the job for which it is intended. See also our 'SPECIAL OFFER' bundled beginners machine at the top of this page.****Please note this machine is for 220/240volt use only****<h3 class="product_price"> Priced from:£49.79 (£57.26 Including VAT at 15%)</h3>P.S is this a good deal
ActionTekJackson Posted February 4, 2009 Posted February 4, 2009 (edited) hi im just about to buy a ball mill and was wondering will this do if i buy a lead media (i hear thats the best for the job) and if so what size of media would i buy with it? http://www.manchesterminerals.co.uk/acatalog/10-006a.jpg<a href="http://" target="_blank"></a><h3 class="product">TUMBLER 900gm BEACH +BARREL(for stone)</h3>Ref: 10-006 TUMBLING MACHINE.This is a low cost and popular introduction to pebble-polishing for people of any age and it is supplied with a 900gm capacity barrel and full instructions.If spare barrels are required see Ref 10-011 in this section (or 10-012 for vaned barrel to use with metal)This is a good value machine, ideal for beginners or those requiring only a small output from their machine. Not as versatile as the twin barrel units but still capable of doing the job for which it is intended. See also our 'SPECIAL OFFER' bundled beginners machine at the top of this page.****Please note this machine is for 220/240volt use only****<h3 class="product_price"> Priced from:£49.79 (£57.26 Including VAT at 15%)</h3>P.S is this a good deal I see this is your first post. There are specific threads on this forum for building ball mills, as well as purchasing ball mills. Basically all you really need to keep in mind is 1. will it sustain the weight of both my media and BP(or other substance to be milled), In other words will the motor turn the loaded mill at a sufficient RPM to effectivly grind with the media? 2. Does the milling container have any incompatabilities or safety risks with my media or substance to be milled. Metal milling jars/barrels are not really recommended, however, brass and other types of non-sparking/reactive metals are usually fairly safe. PVC and hard rubber seem to be the best. This same rule applies to your media as well. There's more to consider but I think you can probly search the rest. Edited February 4, 2009 by ActionTekJackson
tentacles Posted February 4, 2009 Posted February 4, 2009 Welcome to the board - I don't think I'll be the first to advise you to build your own, if you have any small skill at making things. Not only will you gain experience and skill, you'll end up with a better mill than you can buy, short of buying a Burgess mill and shipping it from the states. As to the device pictured, that is NOT a ball mill - it's a rock tumbler. Tumblers rotate too slowly and can't handle the kind of weight you're going to need to put in to mill BP. Also, it's tiny - I believe you can mill about 200g of BP per batch in a jar that size, and given the 24+ hour milling times it will take since it turns too slowly... If you make a mill, you can either make your own jars, or buy Lortone or similar tumbler jars. My preference is to make them, it's not terribly difficult, can be done with a minimum of tools and you can make the jars as big as you want. My jars are 8" (~20cm) diameter and I mill 1.35kg batches with it undercharged with media. Once I get a full charge in there, 1.75-2kg batches will be no problem. And it's only takes 2 hours to mill a batch of BP from prilled KNO3 and chunks of charcoal. Not even starting with airfloat!
Simoski Posted May 23, 2018 Posted May 23, 2018 (edited) I try to run 2 batches a day 12 hours at a time, I'm pretty sure the reason for my clumping ( coagulation ) is fine particle size, even though I have to scrape it out of the jar the BP is dry and very fast Edited May 23, 2018 by Simoski
Arthur Posted May 23, 2018 Posted May 23, 2018 My experience with clumping has always resolved to damp ingredients. The charcoal is first suspect, the nitrate my second suspect. Usually you should dry the powders gently before weighing out as you could include the moisture in the weighing and get odd compounds.
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