I run my prilled KNO3 thru my powder grinder before weighing. Breaks it up enough so it mills better.
swamp
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I run my prilled KNO3 thru my powder grinder before weighing. Breaks it up enough so it mills better.
swamp
I've settled at a 12 hour milling time but my ingredients are not pre milled. I was using a blender but it burned out grinding a batch of charcoal so I simplified and work without it. I'm using a mix of .45, .50, .54 and .69 caliber round balls along with three or four 2oz fishing weights in my tumbler. The fishing weights seem to keep the green powder from clumping up as much.
OK, so I ordered some KNO3 and sulfur. Where do you get appropriate charcoal if you don't make it yourself?
I have Tree of Heaven float and Willow course ground on hand. I could spare enough for a small batch. 1 lb batch or less.
PM if interested.
swamp
My KNO3 comes as prills, but I pulverized it to flour using a blender. Sadly I put it in a plastic container and it turns out that if it sits as powder it renders back into a big chunk, so I had to re-pulverize it before milling. The sulfur is already dust. And I pulverized the charcoal to dust with the blender also. So all ingredients are dust when they go in for milling. I had no problems with clumping, probably due to the cylindrical nature of my lead-filled-copper-pipe media. Only a very few "flakes" were stuck to the bottom face of the canister (you can see them on top of the pile above) but if you touch them they turn to dust.
So I can probably get away with much less time. I now have 200 grams of green powder ready for pressing.
How damp do I want to get it, and how full do you fill one of Fly's pucks?
Steve
I only get it damp enough so it starts to clump when pressed against the mixing bowl. If you get moisture coming out the bottom of the puck, way too much.
I have read and have had success with 10% by weight distilled water (or well, I'd be real concerned about public and chlorine content) to green mix. Since we're all doing this in the shop and the like, I just use 10% weight of my green mix in mL. Sometimes a little over but under makes it a near impossible to get what you want.
How full? probably dependent on your press more than anything else. I can't go over 1/3 in the die I have (other source, 2.5") and get a 1/4 to 3/8 puck with a one ton press.
brewer12345, If you can get charcoal from another member, I'd do that. You can get red cedar charcoal from certain pyrotechnic suppliers but you start losing any cost effectiveness at that point. If your concern is just getting a good batch of ingredients, that's certainly a place to start and in bulk, not a terrible way to get other components from what i've seen.
OK, 10% by weight or by volume? mL is volume.Quote:
I just use 10% weight of my green mix in mL.
I've got 200 grams of green meal. So 10% by weight means add 20 grams of water.
I get that you just want damp and not saturated; just trying to get a ballpark of how much to expect to use. Plus it would be good to have an exact recipe to follow for consistency.
Steve
That sounds like a lot of water, start with less and slowly ad a little at a time till it just clumps up. If you are looking for a repeatable recipe start with 20 grams of water which is also 20 cc's and slowly mix in a little at a time to the right consistency then see what's left. The few times I tried to make pucks I always had problems with getting the amount of water correct.
If water runs out when you press it, you used too much. And that's not a good thing, as it leaches out the KNO3, plus makes the pucks take longer to dry. You want to use as little water as possible. In humid areas/conditions, no water at all might be needed.
From what I've read, when you hit the right pressure, the ingredients themselves semi-liquify, (particularly the sulphur), and meld the mix together. That's why you don't need/use a binder such as dextrin, red gum, etc. when pressing powder.
Vettepilot
Mailemaker:
Would you happen to have the time to do a 100 gram test batch, milled only four hours using your setup, to compare performance to your extended mill batch you are currently working with? I'm quite curious about that...
Note that for this to work, I believe you would need to first grind up your potassium nitate in a blender if you are using the prilled form. (Little balls.) And of course, your charcoal as well. Never use the same blender jar to grind different chemicals without a thorough washing and drying first!!
Thanks,
Vettepilot
I pulverize my charcoal, and KNO3 in the blender (separately, after washing). The Sulfur is already powder.
I'll do a 4-hour batch maybe tomorrow. Going to try pressing pucks tonight.
Steve
I wonder if making the powder damp with alcohol instead of water would be any better? Faster drying for sure, quicker recovery time if you accidently got your mix too damp. No leaching of the KNO3.
Anyone here tried it??
(I've read every single post here, but ya know how it is.... when ya get old, your memory is the SECOND thing to go...)
Vettepilot
I use alcohol to dampen powder. Works well so far.
Made my first pucks tonight using my Harbor Freight 12 ton press and the Fly Puck.
Yup, I used too much water. Used a spray bottle and sprayed and mixed until it looked damp. It looked fine on the cookie sheet. But under 12 tons of pressure it really squeezes out the water. At the end I had quite a pile of "mud" on my press cookie sheet. Hopefully it still goes bang. Next time, much less water.
I filled the Fly Puck about half full.
Once pressed, you have to use the press to knock the puck out - you can't use your fingers to push the piston/puck out. I pushed into a piece of PVC pipe.
It was amazing how the puck was stuck to the end of the piston. You could easily spin it but it was well-stuck to the face of the piston. You really had to pull to pop it free.
First puck:
https://i.imgur.com/4hnba6Rl.jpg
https://i.imgur.com/kMpyBREl.jpg
https://i.imgur.com/wKWKoITl.jpg
Spray bottle:
https://i.imgur.com/iWhcCYtl.jpg
https://i.imgur.com/FdeLuD1l.jpg
200 grams pressed into pucks:
https://i.imgur.com/kIo2Mwnl.jpg
Here is what it looked like damp:
https://i.imgur.com/TT10tVLl.jpg
It's interesting the color change from green meal to pressed puck.
Steve
I used an alcohol water mix, but you don't need much to get it to press.
I got too much moisture in some of my early batches and it didn't make much difference in it going bang, just made a mess.
Bob
MAILLEMAKER:
Nice work and very nice photo documentation. Congrats!! Your pucks look great! I bet you're dying in anticipation of them drying out for the next step.
Edit: Just so you know, you can cut plastic separators and press more than one puck at a time. Milk jug plastic would probably work fine. I have some flexible cutting board plastic that I'm going to use. My sister was a gourmet cook and we have a bunch of those here. Very durable but flexible plastic about .025" or so thick.
Also, I just read recently on a pyro site that sells puck dies that highly polishing the dies aids in puck release. They also mention oiling the dies, but I don't think that's a good idea at all myself...
Vettepilot
Nice looking pucks, can't wait to hear how the powder works.
Here is a batch that went for about 5 hours this morning. Because my ingredients are pulverized when they go in, I suspect it doesn't take so long to get a good mix of green meal.
https://i.imgur.com/xkS8ygXl.jpg
I would not think that oiling the puck would be a good idea. I think most of my problem was the oozing of my over-wet black powder mud around the piston. I suspect with a properly-damp green meal there will be less sticking. I'll see tonight - more pressing this evening or tomorrow.
Steve
I have one of Fly's dies. I polish the interior and the ram and it helps get the puck out. Not sure if it made enough difference to justify it, but it sure looks nice and very slick.
swamp