Ball mill costruction - ideas

[pyrosailor99]

Hi,

 

in the past i bought a rotary tumbler (with 2 black gum barrels and red metal frame) and used it to make bp with lead balls for fishing (about 10mm diameter and with hole)

 

my ingredients wasn't very good but i'm sure the KNO3 was 99,9% pure. Sulfur was obtained from a friend that works with plants (colour is the same of waht i see in pyro pictures, and it was powder) and charcoal was made "by hand" from a person i know that gave me the powder that was in the bottom of the bags it sells (i really don't know what wood it was).

 

 

method: after milling each ingredient separately (after a day i hadn're real airfloat powder) i mixed all and milled again for other 9 hours).

 

Result: poor poor poor quality powder. it produce a flame but its'nt fast at all... it's unusable neigher for making black match.

 

 

i tried it many times with different proportions etc... but no luck.

 

then i sold my tumbler as i think it is SH*T because i think that the SOFT GUM of the barrels don't allow my lead balls to really press the chemicals. and anyway it don't support 1kg of media balls!

 

i'm sure that a crucial problem of this was also the CHARCOAL.

 

now i want to restart my experiments and i want to buy willow charcoal (and pine for furure experiments) and build myself a real ball mill.

 

 

My idea is:

 

- to use a washing machine motor.

 

- build my barrel with a 20cm diameter PVC pipe 20-30cm long with caps (wall thisk about 6-7mm).

 

-to use this MEDIA (pay ATTENTION, here i want suggestions!)

 

option1: buy some 40mm pvc pipe (20-30cm long) and fill it with LEAD BALLS and CEMENT (so i will have about 5 or 6 30cm long pvc rods that weight much!) - my fear on this is the electrostatic energy of pvc rods in the barrels

 

option2: (as read on some forum) buy some 2cm diameter brass rod and cut in many pieces 2cm long (TELL ME IF this works)

 

option3: use option1 and option2 together in the same barrel

 

option4: use lead balls for fishing (but i don't want it as they have holes and i know that chemicals enter this holes!)

 

ps. i'm an hobbyst (so i cannot spend much money in media) but i want to obtain high grade bp. i want to make experimetns with stars and over all i want to make high quality Black match!

 

i try experiments by many many years without serious good results.

 

thanks to all will help me!

 

PS. maybe i post this same topic on other forums (other websites). i hope you don't call this Xpost. ;-)

Edited October 6, 2010 by pyrosailor99

[Bonny]

Hi,

 

in the past i bought a rotary tumbler (with 2 black gum barrels and red metal frame) and used it to make bp with lead balls for fishing (about 10mm diameter and with hole)

 

my ingredients wasn't very good but i'm sure the KNO3 was 99,9% pure. Sulfur was obtained from a friend that works with plants (colour is the same of waht i see in pyro pictures, and it was powder) and charcoal was made "by hand" from a person i know that gave me the powder that was in the bottom of the bags it sells (i really don't know what wood it was).

 

 

 

 

method: after milling each ingredient separately (after a day i hadn're real airfloat powder) i mixed all and milled again for other 9 hours).

 

 

 

 

Result: poor poor poor quality powder. it produce a flame but its'nt fast at all... it's unusable neigher for making black match.

 

 

 

 

i tired it many times with different proportions etc... but no luck.

 

 

 

 

then i sold my tumbler as i think it is SH*T because i think that the SOFT GUM of the barrels don't allow my lead balls to really press the chemicals. and anyway it don't support 1kg of media balls!

 

 

 

 

i'm sure that a crucial problem of this was also the CHARCOAL.

 

 

 

 

now i want to restart my experiments and i want to buy willow charcoal (and pine for furure experiments) and build myself a real ball mill.

 

 

 

 

My idea is:

 

- to use a washing machine motor.

 

- build my barrel with a 20cm diameter PVC pipe 20-30cm long with caps (wall thisk about 6-7mm).

 

 

 

 

-to use this MEDIA (pay ATTENTION, here i want suggestions!)

 

option1: buy some 40mm pvc pipe (20-30cm long) and fill it with LEAD BALLS and CEMENT (so i will have about 5 or 6 30cm long pvc rods that weight much!) - my fear on this is the electrostatic energy of pvc rods in the barrels

 

 

 

 

 

option2: (as read on some forum) buy some 2cm diameter brass rod and cut in many pieces 2cm long (TELL ME IF this works)

 

 

 

 

option3: use option1 and option2 together in the same barrel

 

 

 

 

option4: use lead balls for fishing (but i don't want it as they have holes and i know that chemicals enter this holes!)

 

 

 

 

ps. i'm an hobbyst (so i cannot spend much money in media) but i want to obtain high grade bp. i want to make experimetns with stars and over all i want to make high quality Black match!

 

 

 

 

 

i try experiments by many many years without serious good results.

 

 

 

 

thanks to all will help me!

 

 

 

 

PS. maybe i post this same topic on other forums (other websites). i hope you don't call this Xpost. ;-)

 

 

I think you should start by READING the (many) threads on here concerning ball mills and black powder. You will find all the answers you need.

[pyrosailor99]

I think you should start by READING the (many) threads on here concerning ball mills and black powder. You will find all the answers you need.

 

 

Sure, i searched the forum before post this, and i read many other topics on this and other forums (also if i registerd here now) during my experience...

No answer found. can you link me a post where i can read the answer to my question?

 

really anyone before me thought to create high-weight pvc long rod to roll in the barrel as roto-press?

 

Thank you for the reply!

[dagabu]

You are on the right track, in the USA, that would be about an 8" jar with 1" media. I like the brass much better then the lead but consider making the media 1.5x longer then the diameter.

 

A washer motor is fine but make sure it is not inside the same enclosure as the jar in case the jar spills or leaks.

[pyrosailor99]

You are on the right track, in the USA, that would be about an 8" jar with 1" media. I like the brass much better then the lead but consider making the media 1.5x longer then the diameter.

 

A washer motor is fine but make sure it is not inside the same enclosure as the jar in case the jar spills or leaks.

 

I just discovered someone can sell me HEXagonal brass rod. Do you think this hexagonal form may work better?

 

What do you think about my idea of having some big high-weight big-long rod in the barrel? it would be like putting 6pcs of 20mm diameter lead rod... but external is pvc. It may works better or worse of small chunk of rod?

[Mumbles]

The long rods have been used for a long time. They're good at breaking up big chunks of material, but work very poorly at making it very fine. Adding to the fact that it will have a PVC surface, which is relatively soft, there will not be a great deal of productive work being done.

 

Cut up the brass. I have heard that hexagonal brass is more efficient, but get whatever is cheapest.

[dagabu]

The long rods have been used for a long time. They're good at breaking up big chunks of material, but work very poorly at making it very fine. Adding to the fact that it will have a PVC surface, which is relatively soft, there will not be a great deal of productive work being done.

 

Cut up the brass. I have heard that hexagonal brass is more efficient, but get whatever is cheapest.

 

I second Mumbles.

[pyrosailor99]

The long rods have been used for a long time. They're good at breaking up big chunks of material, but work very poorly at making it very fine. Adding to the fact that it will have a PVC surface, which is relatively soft, there will not be a great deal of productive work being done.

 

Cut up the brass. I have heard that hexagonal brass is more efficient, but get whatever is cheapest.

 

Thank you!

 

I'm just now contacted (via SPAM!! ) by a ceramic ball company...

 

i'm requesting for an offer... what do you think is the best size for media in a 250mm ID 200mm long barrel?

i've read http://www.amateurpyro.com/forums/topic/2402-ball-mill-jar-size-and-the-amount-of-media-used/page__hl__ceramic%20size__st__20

but i haven't a point.

 

the bigger media the best is the result? is this the rule? is there a limit to this?

[dagabu]

No, the bigger is not the better in all cases. I suggest that 1" (24mm) be the largest you go with, you will need to fill the jar 1/2 way to get the media to properly tumble. Count on 300-400 pieces.

[pyrosailor99]

I second Mumbles.

 

What this mean? you don't agree with the hexagonal theory?

(sorry i'm not so good with english... )

 

 

yes, i've read that i have to fill my jar half with medias. now i know that my media hasn't to be greater than 24mm diameter.

so i will have medias of 24mm diameter and 36mm long.

 

I'm wondering why this is the best size...

 

thanks for all info.

[dagabu]

What this mean? you don't agree with the hexagonal theory?

(sorry i'm not so good with english... )

 

 

yes, i've read that i have to fill my jar half with medias. now i know that my media hasn't to be greater than 24mm diameter.

so i will have medias of 24mm diameter and 36mm long.

 

I'm wondering why this is the best size...

 

thanks for all info.

 

In the USA, to second means to agree. I agree with Mumbles that you need to use sort pieces of bar, not long lengths.

 

There is a man named Lloyd Sponenburg that wrote the book (literally) on the PVC ball mill jar and he has a list of proper media sizes for each jar size, as I remember, he has 7/8" to 1" media in the 8" jar. Since you are using a 20cm jar (8") the 20-24mm media will work fine since he was looking for media 1/10 the diameter of the jar for the best cascading effect.

 

Here is the deal with hexagonal bar, it has sharp corners, they will wear down faster then you would think. The idea is not to chop the chems with a sharp cutting edge but to crush the chem between two flat pieces to pulverize the chem to powder.

 

Square stock has too much surface to work well since the pressure is much less on the flats and is to small on the edges, the same can be true of hex bar. I prefer round media for general grinding, small flats to small flats cascading down each striking other balls ten or more times every time one tumbles.

 

According to Lloyd's book, the idea is to maintain a tumbling heap that seems to hold at a 45° to 60° angle when turning.

 

I hope that helps some.

[pyrosailor99]

In the USA, to second means to agree. I agree with Mumbles that you need to use sort pieces of bar, not long lengths.

 

There is a man named Lloyd Sponenburg that wrote the book (literally) on the PVC ball mill jar and he has a list of proper media sizes for each jar size, as I remember, he has 7/8" to 1" media in the 8" jar. Since you are using a 20cm jar (8") the 20-24mm media will work fine since he was looking for media 1/10 the diameter of the jar for the best cascading effect.

 

Here is the deal with hexagonal bar, it has sharp corners, they will wear down faster then you would think. The idea is not to chop the chems with a sharp cutting edge but to crush the chem between two flat pieces to pulverize the chem to powder.

 

Square stock has too much surface to work well since the pressure is much less on the flats and is to small on the edges, the same can be true of hex bar. I prefer round media for general grinding, small flats to small flats cascading down each striking other balls ten or more times every time one tumbles.

 

According to Lloyd's book, the idea is to maintain a tumbling heap that seems to hold at a 45° to 60° angle when turning.

 

I hope that helps some.

 

Sure, this helped me a lot!! thank you!

[pyrosailor99]

No, the bigger is not the better in all cases. I suggest that 1" (24mm) be the largest you go with, you will need to fill the jar 1/2 way to get the media to properly tumble. Count on 300-400 pieces.

 

Oh my gold! i'm just calculating that to have 400 brass media 24mm diameter and 36mm long... i need about 16 meter of brass rod.

1 meter of brass bar 24mm diameter is 3,8kg

 

so 400 media will weight 60kg !!! i need the shuttle engine!! :blink:

 

and if i think to the cost of this mega rod.... i'm fryed!

[dagabu]

Oh my gold! i'm just calculating that to have 400 brass media 24mm diameter and 36mm long... i need about 16 meter of brass rod.

1 meter of brass bar 24mm diameter is 3,8kg

 

so 400 media will weight 60kg !!! i need the shuttle engine!! :blink:

 

and if i think to the cost of this mega rod.... i'm fryed!

 

Yes, I know This is why I use a 1 gallon (6" ID PVC jar instead) and count on smaller batches.

[Updup]

Yes, I know This is why I use a 1 gallon (6" ID PVC jar instead) and count on smaller batches.

 

I use 4" PVC jars, and my lead still came out to around $30-$40... and it can handle 200 grams of BP. Only takes 4 hours for lift though.

[KruseMissile]

Make your own. Look up linotype lead on ebay. Melt it in a pot, then pour into a ball mold or a piece of copper pipe for cylinder bars. I'm using .50 cal muzzle loading ammo, but I don't like how I'm losing some of the balls in my mill(it's going into my comps basically). Just looking for a day I can melt my linotype lead with my dad though. GL

[Updup]

Make your own. Look up linotype lead on ebay. Melt it in a pot, then pour into a ball mold or a piece of copper pipe for cylinder bars. I'm using .50 cal muzzle loading ammo, but I don't like how I'm losing some of the balls in my mill(it's going into my comps basically). Just looking for a day I can melt my linotype lead with my dad though. GL

 

Anoter option for the lead is to go to an auto repair store and ask them if they have any lead weights they use for turning your tires... They will usually give them to you for free.

[Algenco]

Anoter option for the lead is to go to an auto repair store and ask them if they have any lead weights they use for turning your tires... They will usually give them to you for free.

 

 

Wheel weight are great for casting media.

I started with pure lead muzzleloader balls, within a month they were 2/3 original size, one month with balls cast from wheel weights show no noticable wear

[Updup]

Wheel weight are great for casting media.

I started with pure lead muzzleloader balls, within a month they were 2/3 original size, one month with balls cast from wheel weights show no noticable wear

 

Funny... My muzzle loading stuff shows no sign of wear.

 

Hmm, can you get brass tube at Lowes?

[dagabu]

Funny... My muzzle loading stuff shows no sign of wear.

 

Hmm, can you get brass tube at Lowes?

 

I will bet that it does. Grind 200g of KNO3, take a look at the powder after it has ground for two hours, it will be gray in color. Thats lead.

 

When I was using lead to grind chems, I lost an average of 5g every time I made a batch of BP. I started with .50" (50 cal) balls and when I melted them down, they were .41".

 

Yes, it took years to wear down that much but now I use ceramic and SST balls unless I am breaking charcoal lumps.

[Bonny]

I will bet that it does. Grind 200g of KNO3, take a look at the powder after it has ground for two hours, it will be gray in color. Thats lead.

 

When I was using lead to grind chems, I lost an average of 5g every time I made a batch of BP. I started with .50" (50 cal) balls and when I melted them down, they were .41".

 

Yes, it took years to wear down that much but now I use ceramic and SST balls unless I am breaking charcoal lumps.

 

I use SS for oxidizers and brass for everything else (BP and charcoal). More often than not I use a coffee mill for most chems before mixing. I have 3 coffee mills on hand, 1 for fuels (shitty red gum and shellac), 1 for metals and 1 for oxidizers.

[dagabu]

That's a darn good program to follow. Separation. I blade grind a lot too but even then I mill BP in the jar.

[Updup]

I will bet that it does. Grind 200g of KNO3, take a look at the powder after it has ground for two hours, it will be gray in color. Thats lead.

 

When I was using lead to grind chems, I lost an average of 5g every time I made a batch of BP. I started with .50" (50 cal) balls and when I melted them down, they were .41".

 

Yes, it took years to wear down that much but now I use ceramic and SST balls unless I am breaking charcoal lumps.

 

Oh I'm not saying that they don't wear, just that it not noticable... granted, I don't mill that often.

[pyrosailor99]

What is SS and SST?

i searched it anywhere on the web... the only idea is it mean Stanless Stell. is it?

[Mumbles]

It is in fact stainless steel.