My homemade black powder

[Super Sneaky Steve]

Just thought I'd share my hard lesson of the day. For puck making you need much less water/alcohol than for screen smooshing. My dies are hydrolocking and not compressing the powder.

Time to wait for it to dry

[Vettepilot]

Well YEAH. For puck pressing, sometimes just high humidity, or a and/or a rainy day provides enough moisture in the powder for pressing. A quick, light mist is enough otherwise. If water oozes out of your powder when pressing, you used too much. I can't imagine a hydrolock....

Vettepilot

[Vettepilot]

I think a lot of people don't understand what's happening when pressing powder. No binders are needed, and barely any water at all. At above 2700 psi, (I believe the powder companies use as much as 3,500 psi), the sulphur plastisizes and glues the whole mixture together. It is not a process like ceramics whereby clay and water make the end result.

Note that the psi is not the psi recorded on a gauge mounted on a jack; it is the actual pounds per Square INCH of area of your pressing die. It has to be calculated via your jack hydraulic piston area, jack psi, pressing die diameter, and ultimate pressure needed, which is 2700 to 3500 PSI. At that pressure, the whole conglomerate glues itself together via plasticity.

This is why a 6 ton jack; 12000 pounds, just barely produces enough pressure with a 2.5" pressing die. A 2.5" die needs 13,247 pounds of force on it to reach 2,700 psi on the product.

Vettepilot

[ButchC]

Dont need to stress about absolute size for screening - look at FFFg - Wano- Goex - Swiss - they all a little bit different
As well the numbers for screening always quote a percent held on each size screen and percent passed through - they dont tell us how vigorously they shake the screens - its an industrial process with a whole lot of variables - each factory would have a protocol designed to suit their purpose - this is why we get more variation in the FA grade powders - in most cases it is the same powder just processed a little differently.
A few microns either way does not matter - the important part is even kernel size - and even that is a bit flexible

While I don't disagree about stressing on mesh size, that particular item is completely not right. The larger the number, the large the hole size. Totally different units, way too small in this case.

[Super Sneaky Steve]

This time around I just used a large C clamp to press.
On page 78 of this book the guy says low pressure is better for speed.

http://pyrotechnic.narod.ru/Black_Powder.pdf

I'm not sure if what I made will be too crumbly or not. I have a 1 ton arbor press. If that's not enough I'll have to shop for a 6 ton bottle press. I'll report back in a few days after drying.

[Super Sneaky Steve]

Well, my C-clamp bricks are very brittle. Not much advantage over wet screening. I haven't tried to corn them yet as it will take a few more days but I've ordered a 6 ton press and a 30mm small mould to get the most compression.

[ButchC]

You might want to try re-pressing with the arbor press. I've found them to hold together pretty well. It won't get density where you need it for cartridge guns but it certainly beats wet screening.

[Super Sneaky Steve]

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

This puck die just came in the mail. I have to say it's very well made. The fit is so tight you'll feel some vacuum trying to pull the pieces apart. It only makes 30mm disks so quite small but if you're trying to concentrate the power of your press it should do nicely.

Now, it is steel but I thought the aluminum moulds wouldn't stand up to many tons of pressure.

[Faret]

I think I used 4% by weight water to green meal for pressing pucks.

[Super Sneaky Steve]

Willow charcoal production went perfectly today. I made just under a pound and all it took was 1/4 bag of briquette charcoal as fuel. I used a large canning pot with a smaller 12L pot inside. Large pot got many holes drilled underneath and inside pot got one hole at the top, although it didn't really need it since the lid stays on very loosely. I put two layers of charcoal on the bottom along with the canning rack. It burned for about 1.5h then I had to refill it because it wasn't quite done. Another 45 minutes of cook time and it was done. Charcoal was cooked all the way through. I ground it using a combination of an electric coffee grinder for the larger bits and a manual grinder for the smaller bits.

[Eddie2002]

All this talk about using PVC pipe makes me wonder if the grey schedule 80 stuff would be strong enough to use as a die.

[Super Sneaky Steve]

Today's observation is that slow cooked charcoal is much more robust and dense than leftover fire charcoal. Much harder to snap.

I'm looking for a better way of grinding it. Right now I'm using an electric coffee grinder for the larger bits and for bean sized bits I used the small manual grinder. Very slow but works well.

I just ordered a malt mill.
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

I should be able to toss the whole batch in there and have it come out relatively fine. If not fine enough I can sift and and throw the rest into the manual coffee grinder.

[henryinpanama]

In the category, "Yes, an old dog can learn new tricks", I placed my very slow burning powder in an aluminum pan and put that on top of an oil filled space heater for a few hours. Then I laid out about a 4 inch strip of powder for a burn test. The powder, which previously burned at a slow enough rate to see the progress, disappeared in one flash. Conclusion: the powder that I thought was dry wasn't. Now for a warm enough day to go to the range.

I kept the heater on low, so the powder never got warmer than about 110F.

[ButchC]

we have a different opinion (thats ok) - yeah wet screening comes up short on density (about 25% less at my place) but has many advantages
#way easier to do
#dont need a press - dies - grinding equipment
#can go from raw meal to finished powder in the one day
#much better control of kernel size
#by weight the powder is equal energy to pressed pucks
I started out with screened powder and the only reason I do pressed pucks is loading density in cartridge guns - the only reason.........
I live out of town and have room around me, maybe thats a factor I didnt consider?
Everybody does stuff different but for me screened beats the pants off pressed pucks as a process - if you dont need the density (muzzleloaders and cap and ball pistols)

As you say, that's OK. However, my enthusiasm got away from me. You're absolutely correct with all of your points. I should have backed down on the certainty there and gone with: "for a limited volume, any compression is going to beat screened, the more the better". In that case the 1 ton would be a step up from the c-clamp and certainly screened if volume was the concern as you point out. Not going to attain commercial volume to volume comparison but it'll get Steve closer with the tools on hand. All good, I think we're saying the same stuff once I get it spelled out better.

Steve: sounds like your charcoal batch should have a good bit of creosote and other volatile compounds left in it. That'll make a nice fuel and what's said to be a softer fouling powder. Can't say I have had a lot of luck noticing the difference yet but perhaps my charcoal ended up a little more "well-done".

[LAGS]

@eddie.
I did make some pressing dies out of PVC pipe.
I used the regular schedule 40 conduit glued into a Coupling to double the thickness.
It did work for a while.
But it did eventually split after the tenth Batch I pressed.
IMO.
The PVC would work for doing a few pounds of powder if you are not making bunches of powder.
And replacing them when they crack is easily doable.
I use to get all my scrap PVC pipe off construction sites I was managing , so there was no cost to me.
But I bet you can pick up scrap PVC on local construction projects in your area in their Trash or just ask the plumber , electrician or Landscaper for some scrap.
But to buy the PVC you need from a hardware store would cost you more than buying a Die Set from Fly

[Super Sneaky Steve]

In the category, "Yes, an old dog can learn new tricks", I placed my very slow burning powder in an aluminum pan and put that on top of an oil filled space heater for a few hours. Then I laid out about a 4 inch strip of powder for a burn test. The powder, which previously burned at a slow enough rate to see the progress, disappeared in one flash. Conclusion: the powder that I thought was dry wasn't. Now for a warm enough day to go to the range.

I kept the heater on low, so the powder never got warmer than about 110F.

I bought a dehydrator for my powder but I'm a little afraid to use it. The Goex SDS says the auto ignition temp is 395F on the low end and my dehydrator would stay well below that, but you'd have to be sure there were no alcohol vapors left. I bought the fruit roll up attachments which would be good for loose powder.

[Vettepilot]

Why's that Indian Joe? How about 50/50 alcohol/water?

What of methanol, (so called "wood alcohol") instead of isopropyl?

Just curious, and respect your opinions and experience...

Vettepilot

[Vettepilot]

I'm seriously thinking of throwing together a vacuum chamber for drying my powder. (Already have a couple of vacuum pumps and have been toying with the idea of making a vacuum cannon for my daughter and I to play with.)

Yeah, I DO love to tinker... ;~)

Vettepilot

[maillemaker]

I bought a dehydrator with no temperature adjustment. Fully assembled, the pucks were reaching about 120F in the top trays of the dehydrator, measured with IR thermometer. I think this is safe. For a lower temperature, you can remove the top cover while it is running.

They also make dehydrators with temperature adjustment that goes down to like 105F as I recall.

Here are the results of my first 600 grams of production. Some of it was lost for burning and doing comparisons with Goex grain sizes.

195 grams 2F
195 grams 3F
175 grams fines





I think the different colors are the stuff I ground up today vs. the stuff I had ground up a week ago. Interesting.

Steve

[Hotfxr]

V.P., Trying to understand why you would use alcohol in the first place. When making pucks, I don't even spray a mist of water over the powder, the 50%-60% humidity is more than enough to make a solid puck. I bought a dehumidifier to dry out the pucks, but found wrapping them in butcher paper and throwing them in a wood box for a couple of months dries them out more than enough. I don't make screened powder any more, but when I did I just used as little water as possible to "dough" up the powder, screened it and set it out in the sun for a couple of hours. During rain days, under a 60 watt bulb (about 36" above) for a couple of hours did the same. Threw it into a jar with a couple of desiccant packs and even the next day it was ready for use.

Please note, this is not criticism, just curiosity.