Algenco Posted October 18, 2012 Share Posted October 18, 2012 Anyone considering these from Harbor freight, now's the time to get it for half price sale good thru 10/29 http://www.harborfreight.com/dual-drum-rotary-rock-tumbler-67632.html?utm_medium=email&utm_campaign=4212a&utm_source=1003 Link to comment Share on other sites More sharing options...
eb11 Posted October 18, 2012 Share Posted October 18, 2012 i bought this same 1 it worked good for me Link to comment Share on other sites More sharing options...
dagabu Posted October 18, 2012 Share Posted October 18, 2012 It's a fantastic way to start the hobby. One word of caution, the belts are junk, go get a belt for a vacuum cleaner instead, they never break. -dag Link to comment Share on other sites More sharing options...
nater Posted October 18, 2012 Share Posted October 18, 2012 I have not had any problems with the belt mine came with. The tension was not right out of the box, but that is easy to adjust. Link to comment Share on other sites More sharing options...
TheArchitect23 Posted October 18, 2012 Share Posted October 18, 2012 i have 4 of those, and a single drum.alot of people knock them and the belts. i have never broken a belt. properly tension the belt and you'll be fine.use the right size lead media,( i like .50 cal lee muzzle loader balls, cast in a 20.00 mold ) and increase the thickness of the rollers, i can run all 4 units with both drums getting about 2 lbs per run.its a good place to start. you can also search for sealed DC motors ( geared ) 80 rpm that fit into the side case to increase the power if its a bit sluggish or stalls on you. Link to comment Share on other sites More sharing options...
Peret Posted October 18, 2012 Share Posted October 18, 2012 I picked one up yesterday, the last one on the shelf in the store locally. I already have two of them but one is out of action. I've heard people say they don't have trouble with the belts, and I don't understand. Maybe they don't use the tumbler enough, because I was going through a belt a week. Eventually I changed over to a polyester reinforced belt, and that was the last time I had to replace one. Recently though the mill stopped turning, and I found the reinforced belt had worn the small pulley down into a cone and a separate washer - hence the "out of action" comment until I make a new pulley out of metal. I was using a Gates 2L130 (McMaster Carr p/n 7881K14), which is really much too stiff to turn round the half-inch pulley as well as being quite abrasive. I think I'll replace it with this one from Grainger (p/n 13V773), which is more flexible thanks to the cogged construction. Link to comment Share on other sites More sharing options...
nater Posted October 18, 2012 Share Posted October 18, 2012 I've heard people say they don't have trouble with the belts, and I don't understand. Maybe they don't use the tumbler enough, because I was going through a belt a week. I don't run my mill nonstop like some people do. I also only run this one with one loaded barrel at a time. Maybe I'm just getting lucky. I'll be upgrading mills this winter anyway. My wants have outgrown what I can mill in a batch with this one. Link to comment Share on other sites More sharing options...
Algenco Posted October 18, 2012 Author Share Posted October 18, 2012 I ran the single drum version pretty much non-stop for 6+months, no belt problems at all, still on the original beltI've heard of lots of people having problems, maybe it's an alignment problem? They're great for getting started and the sale price makes it even better Dan Creagan has about every style/size ball mill available but still uses the little HF tumbler for certain projects Link to comment Share on other sites More sharing options...
Juiceh Posted October 18, 2012 Share Posted October 18, 2012 (edited) These mills are ok. They are a nice place to start in the hobby, you don't have to spend too much on milling media for them either. I have bought 2 of them when they were on sale in the past. I've exchanged them with no questions asked multiple times, with no receipt + with the modded drive roller installed & no mill jars(they were contamed with BP anyway). As a result I have a few extra milling jars for milling different stuff and a new mill whenever one dies. The motors can burn out if the mill stops during a run and the power isn't cut. Bearings can get shitty, had a bad bearing fresh from the factory with one unit. If you get the belt angle & tension correct these units have a decent lifetime. I house my BP mill inside a 4 legged box with ~3" of heavy duty foam under each foot. The foam footing helps keep the entire assembly rocking/jostling and will help keep a mill from slowing and getting stuck. I always swap the drive belt for the upgrade belts that are available, I always take the upgrade belt off and put the OEM one back when they need to be returned. Slap the used upgrade belt on the next replacement mill, gorilla glue a length of larger hose onto the drive roller, oil the bearings and adjust belt tension and you're good to go again. It does really help to have a set of those snap-ring pliers for modding these. Without one removing the rollers are pretty tough.. Each mill jar can make 300g of composition in 6 hours. I use one mill for BP with lead media and the other for Milling Perc\catalyst for whistle and strobe premixes with ceramic media. Everything has a dedicated jar & media.The ceramic media is way lighter than the lead and the jars turn much easier so I don't have that mill setup with the foam feet. I really want to move up to a much larger setup though. I'd love to be able to mill up like 30 Lbs of BP in one run. Edited October 18, 2012 by Juiceh Link to comment Share on other sites More sharing options...
usapyro Posted October 19, 2012 Share Posted October 19, 2012 (edited) What type of belt did it come with? Habor freight in the valley sells new V belts now that I don't think will break. I just saw them and I bought four today for my small mills just in case. LoL... The circular round belts break in a few weeks or less. I also changed the belt tension to be as little as possible without slippage. Edited October 19, 2012 by usapyro Link to comment Share on other sites More sharing options...
Peret Posted October 19, 2012 Share Posted October 19, 2012 Well I don't know if this is normal now, but I unpacked my new one from its box tonight and found a packet of FIVE spare belts inside. Someone must be listening to the customers. The 3 pound single drum has a round O-ring belt. The 6 pound dual drum has a V belt, but it's made of the same soft stretchy O ring rubber with no reinforcement. Cracks appear in the outside surface after a while and shortly afterward it breaks. It probably helps if you don't stretch the belt and have it under tension, but then it slips. The original V belt is not a standard profile, so far as I can tell, being deeper and narrower than a 2L, but it appears to be the standard 40 degree angle. The unstretched circumference is 12 inches, but I found from experience that an unstretchable 12 inch with reinforcement is too small and can't be fitted without the pulleys touching. Link to comment Share on other sites More sharing options...
usapyro Posted October 19, 2012 Share Posted October 19, 2012 Now here is an interesting question... Has anyone ever had one of their motors go in one of these? Link to comment Share on other sites More sharing options...
NightHawkInLight Posted October 19, 2012 Share Posted October 19, 2012 Now here is an interesting question... Has anyone ever had one of their motors go in one of these?Yeah I had a motor burn out. My mill had lived a satisfactory life by that point. I also had the original belt break in a few hours of use. It was made out of very cheap rubber. Easy enough to replace that it's not worth worrying about. I just might have to go out and grab another one of these with this sale going on. Link to comment Share on other sites More sharing options...
Mumbles Posted October 19, 2012 Share Posted October 19, 2012 Even if you're moved on to bigger and better mills for production of black powder or certain stars, these small ones are still handy for grinding small quantities of chemicals. Remember that a larger mill jar also requires a larger charge otherwise you cause undue stress on the media. Link to comment Share on other sites More sharing options...
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