Very discouraged

[ballmill]

I've tried everything to make fast BP for lift but nothing seems to work right. I've tried lifting a dummy shell out of my mortar but so far it's only going about 25 feet up, even when using more lift than that's called for. The following are the steps I have taken so far in order to make BP lift, but nothing seems to work. I'm at the point where I'm ready to just go dump money for commercial bp...

 

- Dried in the oven separately 425g KNO3, 85g willow charcoal, (not dried) 56.7g sulfur.

-Charged my 6" mill jar half full of lead media and 1/4 full of comp.

- Milled these for 2 hours, at the 2 hour mark comp started to cake up at the opening so I figured it was done milling.

- Granulated 226g with 22.6g of red gum dissolved in 1/3 cup denatured alcohol through a 4 mesh screen per Ned's instructions on skylighter.

- Let dry overnight.

 

Shell weighed 160grams so I used 18g of 2FA lift. The 3" shell was gummed over to slide down the mortar nicely, with about 1/16" clearance. Went up about 25 feet..

 

The meal nor granulated lift doesn't seem to burn fast enough. I've tried everything I could... can someone please offer some advice? The ONLY thing I can think of is that my granulated lift wasn't dry yet. How long does this type of lift take to dry?

[FREAKYDUTCHMEN]

10% redgum is way too much.

 

250 grams of powder should be ok to mill in one time in a 6" jar, to start it's better to mill for at least 6 hours.

 

With good liftpowder clearance should not be an issue really.

[ballmill]

I would mill for longer, but the powder just cakes up at the opening of my jar right after I break it loose.

 

Your right, I made a mistake with the red gum. I misread it.. it's supposed to be 1% of the weight not 10%. Thankyou, I will now try and granulate another batch and will update with the results.

[NightHawkInLight]

You can also try granulating with no binder at all. The granules are fragile enough that they will crumble under any serious pressure, but they stay together well enough in a lift bag. It's made fine lift for me in the past.

[Algenco]

too much red gum

Dry longer

 

everything else looks right, that's the proper loading for a 6" jar,

My bet is it wasn't dry

 

what variety of Willow?

Edited March 13, 2011 by Algenco

[Algenco]

paste a few layer onto a baseball for use as a dummy load

[Arthur]

If it clumped in the mill it was NOT dry enough. Usually 2 hours is not enough try 5 or 8 or 10 hours. What you have left can go back in the mill once it is dry then mill it for several more hours.

 

From reading several posts red gum will act as binder and will speed the powder up to 1.5% then the powder slows down past 2%. So you may want to make another batch and blend this batch in with fresh mix til the red gum is down to 1.5%

Once you have paid for the alcohol needed to moisten with red gum, you will understand that water/dextrin (or sgrs) makes as good a binder and the solvent is cheaper!

 

Normally one makes powder in advance and it may stay in a slightly warm place for a week or more. when you make powder for an urgent need put the grains in a warm place after weighing them in their container. When they reach constant weight they are dry enough.

[Peret]

Water plays an important part when granulating powder, by partly dissolving and redistributing the nitrate. I'm not convinced that granulating with alcohol would be as effective. I never use any binder with my BP, just moisten with water and push it through a screen. When it's dry I screen it again, and only about 10% of it comes through as dust - even that is not dust, just small grains that serve very well as Meal D.

[ballmill]

If it clumped in the mill it was NOT dry enough. Usually 2 hours is not enough try 5 or 8 or 10 hours.

 

I dried each chem in the oven and they all came out looking and feeling very dry. From what I read, up to a certain point the powder will start to clump and that will signify milling is complete. I would mill for longer but I can't because once it clumps, nothing is being milled.

 

Thanks for all the info, I will be granulating with just water to see how that goes, along with my new batch of bp with 1% red gum, not 10% like I originally put in.

[ballmill]

 

 

what variety of Willow?

 

It was from customcharcoal

com. Im guessing black willow?

[Mumbles]

No idea of the variety, but I can vouch that his charcoal is very good. It may however not be all that dry. My mill would cake up even with freshly dried nitrate. To keep milling after it cakes, just break it off the walls. I would frequently give the jar a good rap with a rubber mallet every 30 min or so to help keep it off the walls. When it does really cake, I take a butter knife to it to break it off the walls.

[jimbo]

my tumbler won't mill over 100g of b.p no matter how long I mill it for,its faster for me to mill 100g for 4-5hrs per jar than to try to mill more for longer so I get about 400g of lift quality b.p per 9-10hrs of milling time,try smaller batches,my first batch was perfect,plus I wanted my tumbler to last so I never overload it.

[50AE]

Red gum has a very high fuel value, it needs a lot of oxidizer. 10% is way too much.

[ballmill]

Thanks for the help everyone.. I was able to try it again with the proper amount of red gum (2.6g as apposed to 26 grams) it worked great! Very high lift and loud.

[pyrogeorge]

Have you got ball mill or rock tumbler?

as for red gum,use 2-3% not 10%.

[marks265]

I have to add my 2 cents here, hopefully it will save some people some time and expense. I feel it is good food for thought.

 

 

The addition of red gum is not necessary. It is expensive. The use of alcohol is another expense and I only use it sparingly to keep the dust down. Once wetted I put the alcohol away. My advice is to try to make good powder without the extra chems. It has been done for centuries without red gum I would have to imagine. Additionally a personal goal I have, is to keep it simple and cheap. The cheaper I can make it as compared to commercial powder the better I feel!

I do add a binder however, which is dextrin, where I add an additional 4 percent. I used to add 5 percent and now I am working my way toward 3 percent. IN MY EXPERIENCES, I have tried converting my own corn starch to dextrin. I have found it inferior to commercially made dextrin. I have cooked, stirred, and recooked at several different temperatures and color hues thinking I did a good job at converting. I will not use homemade dextrin anymore. Yes, it does work, but I can use a lot less of it in black powder and in star binding as well. I can only suggest that you try commercial dextrin to compare. I have a 50 pound bag of corn starch that is going to meet the garbage truck pretty darn soon, else use it for lawn fertilizer. In my ranting I only ask that you consider this in your trials. With the disclaimer "IMHO"of course.

Mark

[optimus]

I have found it inferior to commercially made dextrin. I have cooked, stirred, and recooked at several different temperatures and color hues thinking I did a good job at converting.

 

Are you using white or yellow commercial dextrin?

 

I've only tried the white stuff and it was inferior to my homemade yellow stuff...

[marks265]

Are you using white or yellow commercial dextrin?

 

I've only tried the white stuff and it was inferior to my homemade yellow stuff...

 

Ah yes, good question Optimus. I use yellow dextrin and it is food grade.

Mark

 

edit: Now that I think back. I have tried commercial white dextrin.That particular product sucked BAD.

Edited March 15, 2011 by marks265

[NightHawkInLight]

Try using liquid laundry starch as a replacement for dextrin and SGRS(which I suspect is what the starch is anyway). I think you'll be impressed. Moisten star comps with about 50/50 liquid starch and water.

[Mumbles]

Laundry starch is just essentially very thin wheat paste. Whether or not it is cooked at all is unknown, but cooking would make it a better binder. All of these vegetable adhesives are related to one another though. Commercial starch will have some preservatives in it to allow it to be stored at RT for extended periods of time. I've heard rumors it's formaldehyde. No idea if that's true or not.

[ballmill]

I finally got it right and made some nice BP. I also milled up some rocket mix and fired my first cored BP rocket! It flew great and was very loud at takeoff.

 

I have a tub of not so good BP left that I'd hate to see go to waste.. can I use this for star prime?

[dagabu]

Sure! In fact, a little dross from high S BP works nicely for that. Why not make a cored rocket from it and see what it does? It may be a long, big, lazy tail and not lift much, but it would be pretty

[ballmill]

Good idea.. I actually made a quick end burner with it using a broomstick for a rammer but after it didn't lift, I remembered that end burners require a hotter fuel. I'll be shooting some more this weekend complete with videos.

[ballmill]

Dagabu, good call on trying to use it for a core burner. I rammed and tested one on my homemade tooling and it took off with a loud roar and very fast. I'm going to use this mix instead of my 60/30/10 for the remainder of the tubes I have.

 

Since my tooling works so well, I think I'm going to make a 3 lb set in the near future using the Rocket sketcher.

[dagabu]

WHOOT!!!

 

Now, close your eyes and listen to that "WHOOOSH!" again. Great job on that and yes, do use the RTC, it helps loads in regards to getting all of the distances just right.