Ball Mill Type / Size / Brand

[srbrownell2000]

Where is a good place to get bar stock? I have checked with two stores here in town but they dont sell it.

 

Seth

[skydivemd]

Could anyone weigh in on the use of schedule 40 steel pipe instead of solid round stock for the rollers? Save a little weight and increased availability...

[Col]

You`ll be ok as long as the distance between the bearings is reasonable.

[Arthur]

Remember though that bar is sold as diameter and tube is sometimes sold as bore, so getting beatings to fit may not be easy. Check the dimensions before you buy too much.

[oldguy]

Could anyone weigh in on the use of schedule 40 steel pipe instead of solid round stock for the rollers? Save a little weight and increased availability...

 

As mentioned above:

Outside diameter of pipe differs slightly from solid round stock, I could never find pipe to fit the 1 inch ID pillow block bearings I wanted to use.

I went with solid 1 inch OD round stock. Cost was not much more than pipe.

[Col]

We don`t have that trouble in eu, almost everything is metric and measured on the od.

The problem i`ve run into is some sellers think a metric 12mm, 15mm or 20mm od bar or tube is close enough to advertise as 1/2", 5/8" and 3/4"...muppets

Edited November 28, 2011 by Col

[Jwdrummer5]

I love my cheap Harbor freight Rock Tumbler. Although i go through belts about every few months

[Peret]

I love my cheap Harbor freight Rock Tumbler. Although i go through belts about every few months

For the 6 pound with v-belts, try a polyester reinforced 2L130, McMaster-Carr stock number 7881K14.

[Karnivore]

What size motor did you use on the homemade ball mill.

[NightHawkInLight]

I'm glad this topic was resurrected. I've about had enough of trying to get things done without a ball mill, and building my own is going nowhere. I've got a $100 gift card on amazon and I'm thinking of using it to contribute toward one of these:

 

http://www.amazon.com/Model-B-Mailer-Rock-Tumbler/dp/B000BUXY0W/ref=sr_1_35?ie=UTF8&qid=1324096097&sr=8-35

 

Or, slightly smaller, but I like the all rubber barrel on these:

 

http://www.amazon.com/Tru-square-Metal-Products-130-Tumbler/dp/B000BUUT6E/ref=sr_1_25?ie=UTF8&qid=1324096086&sr=8-25

 

Does anyone here use a model B tumbler? They say they have a removable rubber liner on the inside but I'm not able to find an image that shows it. The reviews on it are all pretty good, and from people who use them as rock tumblers and run the motors constantly for weeks at a time.

 

There are less reviews to go on for the other tumbler, but I like the all rubber barrel for the fact that it would make a less Hiroshima scale of a bang if anything ever happened, and throw less threatening debris than a metal drum.

Edited December 17, 2011 by NightHawkInLight

[nater]

i am currently using a 6lb harbor frieght tumbler which i can mill about 150g-200g at a time, which works fine for the batch sizes i do now. when i don't need all of my tools to be portable, i plan on building a mill with quart size and gallon size jars per the Spoenburgh plans.

 

i do like the rubber jars on my little mill, they are much quieter than pvc jars.

Edited December 17, 2011 by nater

[NightHawkInLight]

i am currently using a 6lb harbor frieght tumbler which i can mill about 150g-200g at a time, which works fine for the batch sizes i do now. when i don't need all of my tools to be portable, i plan on building a mill with quart size and gallon size jars per the Spoenburgh plans.

 

i do like the rubber jars on my little mill, they are much quieter than pvc jars.

 

Yeah I used one of those until the motor burned out. Too small for my needs. I at least need a 12 lb. Shoot, looks like the 12 lb was on sale yesterday, the price jumped $13.

[Mumbles]

If you have one of the hexagon barreled ones the speed of the stock ball mill should probably be okay. Normally it's a bit low for what we want if you're running round jars.

 

If you don't mind the noise the PVC barreled ones that run at the correct speed are about the same price.

 

http://www.ebay.com/sch/rockhound.101/m.html

http://www.ebay.com/sch/hobfir/m.html

[NightHawkInLight]

Those are good deals. Maybe I can sell my amazon credit. I've always liked those mills better.

[Mumbles]

I had one and I really liked it. In the long run I'd prefer a jar without a reduced opening, but it's really not that bad. You can still pretty easily get your hands in there to clean and stuff. The rubber cap secures and comes off very easily, as long as you have a screw driver present. There were times where I misplaced it and tried to use my keys and stuff. Just keep a screw driver around.

[oldguy]

None of those rock tumblers on ebay have a TEFC motor.

I em'ed them and asked.

[PyroAce]

What are the ideal RPM times for ball milling Black Powder. I have a 6lb rock tumbler, the size of the jar is 200mm diameter and 120mm depth, I have measured the RPM of the jar and it's doing about 30 RPM What kind of milling time would be sufficient? I don't really wan't to go and buy a smaller jar if I don't have too, I was originally going to buy the double 6 lb tumbler which has two 3lb jars, that way I could use just one jar and fill it good with media and not burn the motor out, I decided to go the single 6lb thinking that bigger is better, but I have since found you need to fill them half full with milling media, then 1/4 full of the chemicals, with the single 6lb drum it appears that when I fill it with about 6lb of lead media it doesn't really fill it up half way.

 

How much does RPM really effect a batch of Black Powder, is speed really instrumental in making powerful Black Powder?

[Mumbles]

The pound rating on rock tumblers is for rocks. You'll probably be at least doubling that weight in lead. My 15lb jar takes around 30lbs of lead to fill it up properly for instance. Ignore the rating for the mill, and actually fill it up with lead to the proper level. For your jar the optimal speed is somewhere around 60-70 RPM. You're probably going to be looking at 8-12hr to get good BP out of a mill like yours at your current RPM. It might go a little faster, or a little slower, but only trying it will tell.

[allrocketspsl]

None of those rock tumblers on ebay have a TEFC motor.

I em'ed them and asked.

 

and you better have one

[PyroAce]

The pound rating on rock tumblers is for rocks. You'll probably be at least doubling that weight in lead. My 15lb jar takes around 30lbs of lead to fill it up properly for instance. Ignore the rating for the mill, and actually fill it up with lead to the proper level. For your jar the optimal speed is somewhere around 60-70 RPM. You're probably going to be looking at 8-12hr to get good BP out of a mill like yours at your current RPM. It might go a little faster, or a little slower, but only trying it will tell.

 

 

Thank you very much for the reply Mumbles.

 

I understand now what it means, if you are using rocks, the capacity of that particular jar will hold around the amount specified, since rocks (used for such purposes) weigh about the same, it's not actually the capacity the tumbler's motor can handle, this is what I originally thought, if its a 6lb tumbler the motor can only handle 6lb of materials or it would burn out, thank you for clearing that up.

 

I am going to have a go at an 8 hour batch and see what comes up, if it has some kick then I will be happy, not too fond of a 12 hour mill, but if that's what it has to be.

In terms of how much materials I should be milling, do you think 200 grams of chemicals would be appropriate for this size jar, the way I look at it most people say the 3lb jar should have 100 grams of chemicals so I was thinking 200 grams would be acceptable, but then I wonder if this is wise considering the amount of chemicals that has to be milled by the lead media?

 

I may even buy a dual 3lb tumbler and use the one 3lb jar filled like everyone else does it, that way I get a good RPM and less mill time, I could then keep the current 6lb tumbler to mill charcoal and other chemicals when needed. The other option is to buy a 3lb jar and move the rollers closer together on the existing tumbler.

[PyroAce]

I have put some radiator tubing over the current rollers to increase the diamter of the rollers, the jar now turns at around 40RPM which is better than what it used to run at, I have also added all the lead balls, they sit almost half way in the jar, I am also going to grind 200grams of chemicals and see what results I can get after an 8 hour run.

 

Has someone got a video of what rate good black powder burns at, even if it's just in a pile of black powder burning, it's always good to see how others measure up.

[pyrogeorge]

Hi,

i found a pump motor but without the label with rpm..the only indicator is a shamrock,maybe the logo of the pump..

Do you know how many rpm maybe will be?

[PyroAce]

One other quick question, I wan't to granulate the powder, how much Dextrin should I be adding to 200 grams of chemicals?

 

 

[Mumbles]

About 4 or 5% is fairly typical.

 

I don't know what to tell you about the motor pyrogeorge. 1750 RPM is fairly typical among motors, but you never know. If you want to use it, you'll probably end up having to hook it up to your mill and see how fast it goes.

[PyroAce]

Thank you Mumbles. 10 grams just seems high to me, this will obviously give very hard granules? Adding this much Dextrin won't effect the burn rate?