My homemade black powder

[indian joe]

HamGunner;
One more thing I've noticed. Maytags are the main ones that I know anything about, but an old Maytag washing machine probably has a good motor, with pulley and the drum pulley and a pump pulley, for the taking. I don't know what RPM a tub turns on spin, but I'm thinking two a second, or more. It may be three. Anyway, that is another option. Any appliance repair will have a load of non working machines, if they haven't scrapped them.
Edit: I just pulled the front off my washer and it spins substantially faster than two per second. I was going to count the revolutions on the transmission, and that ain't happening. It is a blur.

I am cheaper than most here but I reckon the motor driving the mill is not a place to save dollars or use scrap.
Open motors will invariably make sparks as they operate + fine dust from an accident with the mill jar during its un attended 8 hour turning (the lid comes off - bearing fails- spindle rubs a hole in the drum - ) I paid a bit over a hundred for a new sealed motor that I can use elswhere if needed, I set the whole deal up on an old table with a long slack vee belt drive so the motor is three feet away from the drum. Pictures of those little mills with the motor just a few inches directly under the drum make me nervous.
Not a problem until something goes astray.

[indian joe]

I made another ball mill that I think will be more efficient than the one I have been using so far. it is a 9 inch OD jar, 7.5 ID and 8 inches long. The ideal RPM should be 68, I have it at 60. This is simply because of what was available for pulleys, I can increase it to exactly 68 by adding some electrical tape to the shaft where the jar rests but I think its pretty good now. As you can see though, the jar isn't half full with media so I will have to cast some more of those balls or maybe fill the rest with ceramic media. This is a very nice jar.

Attachment 292951

Attachment 292952

You cant see them in the pictures but there are stoppers on the driving shaft preventing lateral movement so the jar wont slip off the casters. The 1/2 drive shaft has a plastic tube sleeve that fits over it to ad friction. I gave it a run and the rubber lining in that jar makes things very quiet.

Is ceramic media safe for this ?? might wanna check that.

[Vettepilot]

Very good ball mill operation info, with a calculator you just plug your mill jar numbers into, and an illuminating video, illustrations, etc. Very much worth having a look.

From an earlier post of mine:

https://www.911metallurgist.com/blog...critical-speed

One thing of note, is that they say you don't really want the balls falling. Best grinding/milling occurs at the point just before that speed, when the most amount of media possible is tumbling over and over itself. This seems somewhat counter-intuitive, but is apparently true none the less.

Vettepilot

[almar]

Indianjoe, some ceramic media sparks and should not be used but some doesn't, you need to make sure you have the right kind.

VP: at first I thought that calculator was way off until I saw this the dimension inputs were in feet. It give about the same results as my formula but does not include the media diameter likely because its for very large ball mills (hence the feet) and the media dimensions would not have much of an effect. Either way, I think that if you are really far from this optimal RPM, you might not be getting a very efficient milling, but we all talked about this before...

Once thing to note about new homemade ball mills, I think that you need to check them a lot at first and not leave them unattended for too long until you trust them. This may loosen or heat up, or that jar might come off and like joe said, the spindle will friction burn itself into the jar etc...

[HamGunner]

Well, I will pick up a new v-belt for my mill today and see what speed the larger motor pulley will produce. I am amazed at the speed needed to get the best grinding affect. The cascading of the media along with the powder mixture I guess produces best pulverizing affect and speed is needed to get it to that point.

[HamGunner]

Pictures of those little mills with the motor just a few inches directly under the drum make me nervous.
Not a problem until something goes astray.

I suppose a bit of caution could not hurt a thing. While I am attempting to upgrade my mill to a more proper speed, I will fashion up a divider shelf to shield the motor section from the drum on top just in case. Thanks for the suggestion.

[DoubleBuck]

Myself personally, if I have a free motor at my disposal, and am worried about it being unsealed, I would seal it in a wood crate, or even a cardboard box. But, that's just me. There are ways to be safe, that cost very little money.

[Vettepilot]

Indianjoe, some ceramic media sparks and should not be used but some doesn't, you need to make sure you have the right kind.

VP: at first I thought that calculator was way off until I saw this the dimension inputs were in feet. It give about the same results as my formula but does not include the media diameter likely because its for very large ball mills (hence the feet) and the media dimensions would not have much of an effect. Either way, I think that if you are really far from this optimal RPM, you might not be getting a very efficient milling, but we all talked about this before...

Once thing to note about new homemade ball mills, I think that you need to check them a lot at first and not leave them unattended for too long until you trust them. This may loosen or heat up, or that jar might come off and like joe said, the spindle will friction burn itself into the jar etc...

I rather roughly checked the numbers on that milling site, and I too think that they are close to correct for our use. Since my mill is variable speed, I can adjust it and somewhat tell what's going on by the sound. When I get it a bit too fast, it suddenly gets really loud, which is the balls crashing/falling down. Slow it down a bit, and that racket eases off and becomes more of a steady growl. The speeds at which it does those things correlate with the speeds suggested on that website.

I'm really glad my mill is speed adjustable, and really recommend building a mill out of treadmill motors and controllers if one can. Yard sales and second hand stores are good places to find them. I found mine set out on the street for trash pickup. Great score!!

Vettepilot

[almar]

Well, I will pick up a new v-belt for my mill today and see what speed the larger motor pulley will produce. I am amazed at the speed needed to get the best grinding affect. The cascading of the media along with the powder mixture I guess produces best pulverizing affect and speed is needed to get it to that point.

hamgunner, you may know this but to increase the RPM you need to increase the motor pulley, the RPM increase will be proportionate to the pulley diameter increase. I.E if you go from a 1 inch pulley to a 3 inch pulley, the jar RPM will increase by 3 times...

[HamGunner]

My largest diameter motor pulley ended up producing 45 rpm. Perhaps not the optimum speed, but certainly a whole lot better than the 20 rpm of the smaller original pulley.

I charred up some Sassafras today and I think I ended up with enough < 40 mesh after grinding the coarser stuff and rescreening to make another 2 lb. batch. I have to work tomorrow so will get after it again later in the week. I am hoping that a faster turning mill will not only produce better results, but cut the mill time down a good bit as well.

I plan on milling the finished and screened powder by itself and then rescreening it. Hopefully the faster mill speed will show me better results in polishing the granules than my slower mill speed did before. I did not see much of a change before with nearly 3 hours run time. Hopefully the uniformity and shape of the granules will show improvement now.

[Vettepilot]

Oh yeah! You should notice a very nice difference in milling efficiency going from 20 rpm's to 45.

But remember guys, sufficient milling is critical to good powder, so don't be so anxious to cut down mill time. You can't over mill, but you definitely can under mill.

Vettepilot

[indian joe]

Oh yeah! You should notice a very nice difference in milling efficiency going from 20 rpm's to 60.

But remember guys, sufficient milling is critical to good powder, so don't be so anxious to cut down mill time. You can't over mill, but you definitely can under mill.

Vettepilot

I would be less keen than most of you to increase the speed of the rotating mill drum - find the sweet spot for sure but from there more aint better !

[Vettepilot]

I meant the change from 20 to 45; not to 60. I just changed that in my post.

And Indian Joe is correct. Too fast on the mill is not good. That site I posted explains it all. You want the correct speed, and it's important.

Vettepilot

[almar]

The howitzer has arrived.

[LAGS]

Nice rifle.
Question.
Will the 45/90 also chamber and shoot 45/70 ?

[almar]

it will, although accuracy may be in question

[LAGS]

My friend had a Sharps .
And he fired 45/70 to practice and plink because it saved wear and tear on his 45/90 cases.
Also so it wouldn't kick the heck out of people that wanted to try shooting his rifle.

[DoubleBuck]

Almar;
Nice boots. lol
Congratulations friend, that's a neat one!

[Vettepilot]

Now that's cool. Oh, the gun too!

;~)

Congrats my friend.

Vettepilot

[Trapper-Jack]

I was able to do a little side by side test of my screened and sifted powder against Goex 2F in my Lyman GPR flintlock. The rifle is sighted in for a 50 yard zero. I sifted my powder to pass the 16 sieve and retained on the #30. I used Goex 4F as priming powder for both. Both powders were measured at 70 grains. The projectile was a patched, cast round ball. The range was 100 yards. I was shooting at a paper plate stapled to a cardboard backstop. The plate is the best I can see with open sights at that range. The test was not extensive as the wind came up and blew the backstop over, however the Goex printed approximately 6 inches low. I expected this. My 70 grains of measured home brew also hit 6 inches low from point of aim. All shots fell into a 3 1/2 inch group. After I gathered up my stuff and came in, I weighed the measured powder charges. The Goex weighed 71.7 grains. My homemade powder weighed 47 grains. I have always been under the impression that these powders equal in weight and not volume. My next testing will be at 150 yards and see how they compare. I'm extremely happy with this new hobby.