93 replies to this topic

[knackers]

yes it did make for good discussion, it did get my brain ticking ( it woke me at 4 this morning), and i do appreciate your knowledge, thanks for the interaction

[Labs2008]

Thank you all for the help I am milling a batch now 100grams with about 12lbs of lead and us nickels the jar is barely a third full but will see what happens. I will let it mill for 8 hours. I will make a video of it when it s done. On a side note I experienced my first pyrophoric reaction with my homemade aluminum powder. Not sure why it happened as I opened the jar every 4 hours except at night when i slept then it was 8 hrs. I had just sifted the powder htrough a 10 mesh thn 20 mesh screen and was preparing to sift it through a 100 mesh when i noticed a little smoke and looked to see a nice orange glow coming from part of the powder. luckily i do the sifting outside so i just let it burn in the can it was in. It burnt for about a half hour and was quite pretty at times. 288 grams of al just waisted. but at least know one was hurt. It was so fine it basically just glowed orange and had the occasional flare up of bright white like a lance or something. all was left was alot of aluminum oxide and a half melted can. so wi will be opening my mill jar every 2 hours for now on. 4 good batches and this was number 5.

I will check my lumber supply and verify that the pine is not treated it is the low grade white pine 2x4 construction studs. very rough i will make sure that they are not treated. The hardwood lump charcoal seems to be pretty good as well it crumbles pretty easily with a hammer and when milled is nice and fluffy no stringy grainy looking fiber in it. $3.99 for a 10lb bag is cheap. compared to $10 for the 2x4 by 8'.

thanks again for the help.

Brad

[digger]

yes it did make for good discussion, it did get my brain ticking ( it woke me at 4 this morning), and i do appreciate your knowledge, thanks for the interaction

It made me think too which is good. Sorry to get you up at 4am. I am sure we will have good conversations in the future too, it is all good. It will be a nice addition to the knowledge base that this forum is becoming (although maybe not in the right place as it should have been under the ball milling thread really).

Maybe I will be a little more relaxed in the future when I get over the withdrawal symptoms from this dam nicotine addiction although as you can guess I can get a little carried away sometimes anyway.

Cheers

D

Thank you all for the help I am milling a batch now 100grams with about 12lbs of lead and us nickels the jar is barely a third full but will see what happens. I will let it mill for 8 hours. I will make a video of it when it s done. On a side note I experienced my first pyrophoric reaction with my homemade aluminum powder. Not sure why it happened as I opened the jar every 4 hours except at night when i slept then it was 8 hrs. I had just sifted the powder htrough a 10 mesh thn 20 mesh screen and was preparing to sift it through a 100 mesh when i noticed a little smoke and looked to see a nice orange glow coming from part of the powder. luckily i do the sifting outside so i just let it burn in the can it was in. It burnt for about a half hour and was quite pretty at times. 288 grams of al just waisted. but at least know one was hurt. It was so fine it basically just glowed orange and had the occasional flare up of bright white like a lance or something. all was left was alot of aluminum oxide and a half melted can. so wi will be opening my mill jar every 2 hours for now on. 4 good batches and this was number 5.

I will check my lumber supply and verify that the pine is not treated it is the low grade white pine 2x4 construction studs. very rough i will make sure that they are not treated. The hardwood lump charcoal seems to be pretty good as well it crumbles pretty easily with a hammer and when milled is nice and fluffy no stringy grainy looking fiber in it. $3.99 for a 10lb bag is cheap. compared to $10 for the 2x4 by 8'.

thanks again for the help.

Brad

Interesting. I do not mill my own ally mainly because I can get various grades quite easily at a reasonable price.

I believe that some people use additives such as stearine when milling aluminium, I also hear that some have tried allowing air to enter the mill through a porous plug while milling to allow the oxidation to continue slowly although I have no idea how effective or safe this is.

Do you use a corrosion inhibiting additive when you do your metals milling?

Where are you located Brad?

[Labs2008]

I have not added stearin but am considering it. I do not add anything to my AL. I blend it until it is very course only a few seconds or so. then I add it to a piece of kraft paper and fold the paper over the AL and press it as flat as I can get it. which is not very flat I admit. then I put it in my charcoal cooker and cook it until the kraft paper is charcoal and then I allow a small amount of oxygen in to promote a small amount of ashing of the charcoal paper. I then let it cool for about an hour and blend the result for maybe 20 seconds until nice and consistent. I then add to the mill and if it is a Small batch say 150 grams it will be -400 mesh in 2 days. I believe the cooking process allows a small coating of carbon to form on the AL and as it is milled the carbon is coating the AL as well. My first 4 batches all turned out as good as the $20/lb. Indian blackhead. I can get any size flake i want depending on the mill time and buy doing it myself the cost is only $3 to 6$ a pound depending on what brand foil I get. The msds for Reynolds wrap household foil is 98% AL 2% tin i believe. and my local store brand seems to work as well. I think I just have to open the mill more often especially the finer the particle size gets. The next batch I am going to mill half as long so I can get more larger flakes for my fountains and stars.

Oh yeah I am from a small town in the U.S.

Edited by Labs2008, 12 August 2008 - 05:36 PM.

[Labs2008]

here is a link to my bp after being milled for 5 hours bptest1

the charcoal used is the lump not the pine.

Edited by Labs2008, 13 August 2008 - 12:04 AM.

[BlackMesa]

Hello again, today i made my first granulated BP - before i had only tried meal powder.
My dextrin has not arrived yet so i made it without a binder, through a 20 mesh (maybe slightly higher) with water as the solvent.

the 100g of BP which is drying now looks reasonable but what i dont understand is this:

If the point in granulating is the allow the flame to pass through the granules of BP faster letting the flame spread quicker up the rocket motor... When i pack my granules in with a rammer and hammer, wont they just compact into one solid lump again, simply burning from one end to the other?

[dr thrust]

yes it will, what exactly are you making? with your bp, if its for a lift charge they are left loose in a "lift cup" fixed under the shell to be fired from a mortar, if your using it in a fountain, rocket no need to granulate, have you any books on pyro?

Edited by chris m, 13 August 2008 - 09:47 PM.

[BlackMesa]

yes it will, what exactly are you making? with your bp, if its for a lift charge they are left loose in a "lift cup" fixed under the shell to be fired from a mortar, if your using it in a fountain, rocket no need to granulate, have you any books on pyro?

Book on making black powder only which has left me in a state of lots of black powder and no much to do with it. So rocket is not needed to granulate? shame i spent all that time ramming it through that mesh just to ruin my BP lol

Was planning on trying to do my first rocket

This video shows about half a gramme of my granulated powder - the powder should improve soon as next batch will have willow charcoal (instead of BBQ lump ) rhombic sulphur (instead of flowers)

Edited by BlackMesa, 13 August 2008 - 10:08 PM.

[pyromaniac303]

You can still use it for rockets, in fact it makes it easier to handle when granulated as it pours through funnels and does not create as much dust, you just have to remember to compact it harder to ensure there are no gaps in the propellant which would cause a CATO. As this is your first rocket I recommend you start small, 6mm end burners are excellent and quite safe, they are also cheap to make.

[digger]

Book on making black powder only which has left me in a state of lots of black powder and no much to do with it. So rocket is not needed to granulate? shame i spent all that time ramming it through that mesh just to ruin my BP lol

Was planning on trying to do my first rocket

This video shows about half a gramme of my granulated powder - the powder should improve soon as next batch will have willow charcoal (instead of BBQ lump ) rhombic sulphur (instead of flowers)

Yep it does still look slow for lift but it should be fine for rockets. It will be interesting to see what difference the the new charcoal and sulphur makes.

[BlackMesa]

Yep it does still look slow for lift but it should be fine for rockets. It will be interesting to see what difference the the new charcoal and sulphur makes.

I'll post a video of the new powder when i make it, my rock tumbler ball mills getting a bit worn out i think i shall try to make one when it goes, considering converting a desktop fan for the eae of being able to plug it in and choose mill speed

The powder feels dry in my hand, but it has only been dryig 3 hours since i granulated it, could still be a bit moist inside the grains.

I have a good cardboard tube, nice and thick. Its quite short though, 5cm long with a diameter of 1.2 cm, if i pack this nice and tight with my BP with a bentonite end plug nd nozzle it should be ok? The tube weighs 6 grammes.

Any suggestion of what size hole i should make in the nozzle to ensure take-off and stick length/weight?



- Bit of a mouthful but ideas will help greatly.

[digger]

I'll post a video of the new powder when i make it, my rock tumbler ball mills getting a bit worn out i think i shall try to make one when it goes, considering converting a desktop fan for the eae of being able to plug it in and choose mill speed

The powder feels dry in my hand, but it has only been dryig 3 hours since i granulated it, could still be a bit moist inside the grains.

I have a good cardboard tube, nice and thick. Its quite short though, 5cm long with a diameter of 1.2 cm, if i pack this nice and tight with my BP with a bentonite end plug nd nozzle it should be ok? The tube weighs 6 grammes.

Any suggestion of what size hole i should make in the nozzle to ensure take-off and stick length/weight?



- Bit of a mouthful but ideas will help greatly.

The best way to make rockets is have some decent tooling so that you can make a core without having to drill the bp.

IIRC the rule of thumb is the nozzle is about 1/3ID for cored rockets and 1/5 - 1/4 id for end burners.

To have a quick go I suggest you get yourself an aluminium / wood rod and using a mallet ram in about 1cm of bentonite, 2.5cm of bp then 1cm of bentonite into your tube. Then drill a hole carefully by hand, gently twisting the drill bit back and forth until you hit the bp (about 1/4ID) (obviously wearing suitable protective equipment leather gloves, overalls mask etc).

As to stick length make sure the girth of the stick looks sensible for the size of the motor and that the rocket balances on your finger just behind the motor.

See if it flies if it goes bang make the nozzle bigger if its lazy make it smaller.

Edited by digger, 14 August 2008 - 11:09 AM.

[Pyrogeorge]

Book on making black powder only which has left me in a state of lots of black powder and no much to do with it. So rocket is not needed to granulate? shame i spent all that time ramming it through that mesh just to ruin my BP lol

Was planning on trying to do my first rocket

This video shows about half a gramme of my granulated powder - the powder should improve soon as next batch will have willow charcoal (instead of BBQ lump ) rhombic sulphur (instead of flowers)

This granulated??very slow..maybe you overload the jar..how many grams are totaly in the jar?
Also as they said that willow charcoal is the faster charcoal...but yours BP is slow for lift..

[BlackMesa]

This granulated??very slow..maybe you overload the jar..how many grams are totaly in the jar?
Also as they said that willow charcoal is the faster charcoal...but yours BP is slow for lift..

overloaded what jar?

[Pyrogeorge]

have you got ball mill?what method did you use to make Black powder?