Lift charge not working well under 3"

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Redbullzuiper
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Lift charge not working well under 3"

Post by Redbullzuiper »

Hi everyone,

Ive some trouble with my lift charge. I used to shoot only 2" shells. They worked really well.
Now I start making 3" shells, but they are not going very high. High enough for the effect but still its not like professional shells.

I tested some lose lift charge. Its burns very fast. The paper doenst catch fire. The black powder is made from willow charcoal in the ratio 75/15/10, granulated using a 10 mesh screen.

The dummy shell has a weight of 150Gram.

I used in both tests 15 gram of lift powder. The first test was in a coffee cup made of kraft. It flew not high at all, maybe like 12 meter.

Second I confined the lift charge using kraftpaper and tape. It flew higher then before, like 20 meter. Still it was not satisfying.

Do I have to confine the lift charge better? Or do I have to make faster black powder? Cuse this is the fastest I can make.

Im getting willow charcoal from Ken. Perhaps then the lift powder will be much better. But ive the feeling that my current black powder is allready fast enough for lift powder.

But my birthday is soon, and I want to shoot some 3" shells to the sky. But I really want to make sure they fly high enough. Any tips and suggestions are appreciated.
Mixer
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Re: Lift charge not working well under 3"

Post by Mixer »

Red,
There could be several reasons why you have a problem.
We would need more info to be able to help you, eg your detailed process of making BP, mortar length, clearance around shell etc - although my first guess would be your BP being too weak. Sometimes you can have weak BP that burns fast but lacks force, and this can give you the wrong impression.
I have just looked up my notes ... for 3" shells I used 7% (3fa) of shell weight to reach 250-300ft with BP made the way I mentioned in my earlier post.

Ps Another thought, are you sure you have willow charcoal?
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Boophoenix
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Re: Lift charge not working well under 3"

Post by Boophoenix »

The charcoal shouldn't be an issue. Ken has done his homework on charcoal so the source material shouldn't be an issue.

Mixer is correct more detailed information would be very helpful in trying to diagnose the problem.

It almost sounds like the drying process could have been a little slow and the potasium nitrate tried to recrystalize on ya making for a weak lifting BP. However some of mixers questions could just as well be culprits.

A super important key to BP isn't trying to make the hottest it's trying to make consistent BP. Hottest is only really needed if you are wanting to push rockets to there limits or ocassionally hard breaking shells if you don't wanna boost them. Commercial pyro uses commercial powder just fine and has for many years.
Redbullzuiper
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Re: Lift charge not working well under 3"

Post by Redbullzuiper »

Ok I will give a detailed explaination of my process.

I made my willow charcoal in the summer. So im sure its willow. Its an normal willow which grows at the river banks here in my village.

I make the black powder in the standard ratio 75/15/10 + 3% Dextrin. I ballmill it for like 8 hours, Ken adviced me to only run it 3 hours (I bough his mill), because its very effecient mill.

However, I run it at night. So I turn it off the next morning when awake.

I granulate it using 75% water 25% Alcohol (isopropyl alcohol). I stir it until it has become a nice clay like patty. Then I press it through my 10 mesh screen.

The mortar I use is a fiber glass 3" mortar. I dont exacly know its length. But I guess its arround 50cm.

When you say you use only 7%, thats amazing. How do you put it under your shell? You dont have to confine it at all? Lets say, you put it in a coffee cup. It lifts it even then to a proper hight?

Ive got one video where you can see its not going high at all. I tested some new stars in it. Green to Orange. My camera doesn't pick up colors very well at night.

Thanks for your thoughts on it!
Redbullzuiper
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Re: Lift charge not working well under 3"

Post by Redbullzuiper »

@Boophoenix I didn't recieve my Willow charcoal from Ken yet. Hes working on it. So my current charcoal is what ive left from my self made charcoal.

Here is the video.

https://www.youtube.com/watch?v=x5nahIlYFnI
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Pyro-Gear
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Re: Lift charge not working well under 3"

Post by Pyro-Gear »

What length did you cut your time fuse Red ?
Mixer
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Re: Lift charge not working well under 3"

Post by Mixer »

When you say you use only 7%, thats amazing. How do you put it under your shell? You dont have to confine it at all? Lets say, you put it in a coffee cup. It lifts it even then to a proper hight?

Nothing elaborate just a Kraft paper cone.

How much clearance have you got around the shell in the mortar?
If it is a good fit and you are firing from a very solid base - then it seems the problem must surely be with the BP.
Out of interest what percentage of water/alcohol are you using?
This most probably isn`t the answer, but you could easily drop the Dextrin content to 1% and still have hard grains.
Redbullzuiper
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Re: Lift charge not working well under 3"

Post by Redbullzuiper »

Pyro-Gear wrote:What length did you cut your time fuse Red ?
It was to long, I know :). I made a new spollete with new tubes. It was too long. But even if it exploded at the right hight. It was not high enough. I dont have time fuse, I just make a spollete from a thin paper tube. But these were a bit too long.

In the video of the shell I tested 3 things. Lift charge, stars and spollete. 2/3 failed.
Mixer wrote:How much clearance have you got around the shell in the mortar?
If it is a good fit and you are firing from a very solid base - then it seems the problem must surely be with the BP.
Out of interest what percentage of water/alcohol are you using?
This most probably isn`t the answer, but you could easily drop the Dextrin content to 1% and still have hard grains.
75/25 Water/Alcohol.
The clearence around the shell is about 3-5mm. I will take a video tomorrow from the black powder tested as a lose pile of 2 gram. I think that will help all of you understanding the black powder I have.
Redbullzuiper
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Re: Lift charge not working well under 3"

Post by Redbullzuiper »

I have some Grapevine charcoal also. Hm, will this be a good charcaol for lift? Didn't use it for BP yet. Its from pyrogarage. Maybe someone has experience with this charcoal?
Mixer
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Re: Lift charge not working well under 3"

Post by Mixer »

Red,

I meant what percentage of water alcohol are you adding to your BP.
Redbullzuiper
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Re: Lift charge not working well under 3"

Post by Redbullzuiper »

Mixer wrote:Red,

I meant what percentage of water alcohol are you adding to your BP.
No idea honestly. I just stir until its a clay like paddy.
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biffo
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Re: Lift charge not working well under 3"

Post by biffo »

?
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Lloyd
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Re: Lift charge not working well under 3"

Post by Lloyd »

Bull,
I'm guessing that Biffo posted the question-mark because you cannot ensure the same results each time if you just add alcohol/water 'by eye'.

For reproducible results, you need to accurately measure exactly how much solvent achieves the result you wish, then use exactly that amount per pound of powder again, every time.

Additionally, you need to know the 'mix' of alcohol vs. water, and use exactly that mixture each time. If you're using standard 70/30 isopropyl (as sold in grocer's stores or the local chemist's) then you don't need to record anything but that you're using that. If you're mixing your own from denatured ethyl alcohol and water, you need to both record what you've done AND you need a way to measure the amount of water in your alcohol, since it absorbs more and more moisture from the air, over time and each time it's opened.

Lloyd
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biffo
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Re: Lift charge not working well under 3"

Post by biffo »

Hi Red I know it might be obvious but have you thought about damp ,I know it affects me in that I can make a comp that will lift a rocket and shell in the summer but fails to get off the ground at this time of year. The charcoal really sucks the moisture from the air. Good luck B
Redbullzuiper
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Re: Lift charge not working well under 3"

Post by Redbullzuiper »

@Lloyd

I don't do it by eye. I measure out the Water/Alcohol mixture. I weight out 75ml water and then add 25ml alcohol. If not enough I make more, with the same procedure.

I though he meant, 'How much % Water/Alcohol do you add to the entire mixture?'.
So for example, if ive have 300gram BP, adding 5% Water/Alcohol mixture. I think I misunderstood his question.

@biffo

I don't think this is the case.

I have to mention once again. Im pretty sure the black powder is very fast. I will post a video tomorrow. When lighting 2 grams on a piece of paper. I can't see the flame, its just poof gone. It burns faster then 5/3/2 slow flash (KNO3/Ai/S). Nothing is left on the paper, except some black sweepings. What I think after reading all awnsers. I think my BP has not much power in it.
sambo
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Re: Lift charge not working well under 3"

Post by sambo »

Hiya fella,

one thing you might try is something akin to Ned's baseball tests. Take a shell without any explosive content and fire it. Time how long it stays in the air and from that you can work out if you are achieving a good height, and therefore if your BP is as you want it to be. Increase the amount of BP you are using to gain a suitable flight time.
Redbullzuiper
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Re: Lift charge not working well under 3"

Post by Redbullzuiper »

Yes, that works very well. I dont use a baseball however, but a dummy shell. Which weight about 150 gram
Last edited by Redbullzuiper on Sun Nov 12, 2017 9:54 pm, edited 1 time in total.
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Lloyd
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Re: Lift charge not working well under 3"

Post by Lloyd »

"I though he meant, 'How much % Water/Alcohol do you add to the entire mixture?'.
So for example, if ive have 300gram BP, adding 5% Water/Alcohol mixture. I think I misunderstood his question."
---------------------------------

I took him also to mean how much to the entire mixture. NOW you're saying 5%, but Mixer's asked, "I meant what percentage of water alcohol are you adding to your BP." -- and you answered, "No idea honestly. I just stir until its a clay like paddy." FWIW, 5% wouldn't even come close to making it into a "clay like paddy (sp)". To get to that consistency takes more like 20% or more.

I'm glad you accurately mix your alcohol/water mix, but if you have 'no idea' how much of that mixture you add to your powder, you need to quantify it to achieve consistent results.

Lloyd
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Redbullzuiper
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Re: Lift charge not working well under 3"

Post by Redbullzuiper »

Im sorry Lloyd, my english is not that good. It surely doenst contain 20% dextrin. I just meant with that, that its wet enough so I can make a ball of it.

I will post the video of my BP, it will be much more informative. So you guys can judge, based on the video, how well my BP is. I appreciate the feedback and all the responses.
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Re: Lift charge not working well under 3"

Post by Lloyd »

"Im sorry Lloyd, my english is not that good. It surely doenst contain 20% dextrin. I just meant with that, that its wet enough so I can make a ball of it."
---------------
Ok... to clarify my statement: First, I NEVER mentioned the amount of binder, and you did not, also.

YOU said you add only enough alcohol/water mixture to make it 'wet enough'. My point was that you need to quantify the amount of solvent you add, so you may duplicate your results each time you perform the process.

I think your English is fine. It's certainly better than my German! <grin>

Lloyd
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Redbullzuiper
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Re: Lift charge not working well under 3"

Post by Redbullzuiper »

Thanks Lloyd, will keep it in mind.

Im going to wait for Kens charcoal. As im pretty sure his charcoal will be much better then I have.

P.S. Im from the Netherlands, not from Germany ;)
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Lloyd
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Re: Lift charge not working well under 3"

Post by Lloyd »

"P.S. Im from the Netherlands, not from Germany ;)"
-----------
HEH! SEE! I told you my German was no good! And for that matter, neither is my Dutch! <smile>

Lloyd
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oliverbrown
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Re: Lift charge not working well under 3"

Post by oliverbrown »

Could be the charcoal, problems are more likely to arise from the cooking technique rather than the tree it's harvested from, good idea to rule out the charcoal by testing with a known product.
Is there a chance you got your percentages wrong on this batch, just because it burns well unconfined it may be sub-standard when confined?
Redbullzuiper
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Re: Lift charge not working well under 3"

Post by Redbullzuiper »

As promised. Here is the video. Its 2 grams of BP on a piece of kraft. https://youtu.be/S56w_XUUfYE
Mixer
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Re: Lift charge not working well under 3"

Post by Mixer »

Red,

It`s very subjective looking at a video, but IMO that doesn`t look particularly good - 2g of loose good quality BP should go with a bit of a thump and leave barely any residue.

As we already know that this BP is unable to lift your shell satisfactorily - it seems that your options could be....

!. Try a new batch with Ken`s willow charcoal.

2. If that is no better then re-evaluate your manufacturing method/storage etc of your BP.

3. If there is no improvement, and this is the best that you can get your BP - then you could either add more lift and/or use a longer mortar tube.

There`s something a bit confusing here - your video of the 2.5" shell seems to show it reaching the correct height. Was that using the same batch of lift or a different one?
Redbullzuiper
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Re: Lift charge not working well under 3"

Post by Redbullzuiper »

Mixer,

I confined the lift charge under the 2.5". I wrapped the lift inside a tissue paper and then confined it with some adhesive tape.

As for the 3", I changed some things to make it more reliable. I start using a spollete which contains 4 fuses. So it allways lights.
I can also add some effect in the spollete, which I like. So the lift can't be as confined as I did with the 2.5" shell.
Because it will blow out the fuse, or dont light the fust at all.

I dont have any willow left, so Im going to make another batch of BP this evening, using the Vineyard charcoal and only add 1% of dextrin.
As ive noticed that dextrin really effects the BP quality.

So, the conclusion is.
My BP isn't good enough for lifting shells.
I should confine it more to bring it to a propper height.

Im going to wait for Kens charcoal, as this is my best bet at getting high quality BP.

P.S.
I planted a pauwlonia tree in our garden, this will give me excellent wood for BP in a few years ;)
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Boophoenix
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Re: Lift charge not working well under 3"

Post by Boophoenix »

Red, can you share some details of your cooking method as well? Oliver, touched on this option a little.
Redbullzuiper
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Re: Lift charge not working well under 3"

Post by Redbullzuiper »

I am sorry, I did read over it.

I cut some branches from a willow tree. The sticks were 1 - 1.5 cm in diameter. I didn't let them dry, as it is not necessary according to some topics on APC.
I have not picked up the bast either, as it was not even 0.5mm thick.

I placed the sticks inside a steel like paint pot, with a hole in the lid for the fumes.

I made a fire inside an old oil tone, and put the pot inside it. The fire was hot and good. When cooking a flame is visible at the hole where the fumes take fire.
I let it burn until the flame was gone + an additional 20 minutes. I let it cool down and openend the pot. No ash was visible, only the charcoal converted sticks.

I ball milled the charcoal sticks 8 hours. I ended up with a nice, air float charcoal.

I made 2 batches of BP to test the new charcoal. 1 batch with with pine charcoal and 1 with the self made charcoal.

Both were processed exacly the same. The self made charcoal burned much faster then the pine charcoal.

I have to note that the willow I used was not black willow or weeping willow. But another willow which I dont know the name of. I don't know where black willows
are growing here. We have alot of weeping willows and pollard willows. Should I try one of these? Any of you have tryed it? I also heard oak charcoal is very powerfull.
But can't find any info about it.

I really like this forum over APC, as here are more experienced people and people who really try to help me. Thanks to all of you.

My birthday will be comming Sunday 19th, but I celebrate it Wednesday 22th November. I will make video's of it and post it here, to show what progress ive made since I
started pyro.
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Pyro-Gear
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Re: Lift charge not working well under 3"

Post by Pyro-Gear »

I have to say that some of the guys at our meet were lifting 6-inch shells on my Beech charcoal I supply and that is some cheap charcoal.
Oliver brown makes a valid point on the cooking method, it could be a case of overcooking, anyway I am about to send you some charcoal for your evaluation let’s see how you get on.
Redbullzuiper
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Re: Lift charge not working well under 3"

Post by Redbullzuiper »

Thanks Ken.

Btw, with Oak I meant beech. Was looking for that topic about oak, now you mentioned beech, I remember they were talking about beech. They said beach makes a very powerfull BP.

We got an big beech tree in our garden. Will shave it when we got better weather. And cook some.

The formula for beach, according to them is:
KNO3 73%
Charcol: 18%
Sulfur: 9%
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Pyro-Gear
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Re: Lift charge not working well under 3"

Post by Pyro-Gear »

Not sure who them is but with beech you use 75-15-10 that’s it, I can understand some variations in particular vine charcoal it has a rather high ash content.
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Boophoenix
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Re: Lift charge not working well under 3"

Post by Boophoenix »

Here's one of the better resources and extensive testing I'm aware of on charcoal. While likely most is associated to US materials I'd think you could find some commonalities in other regions.

http://www.creagan.net/fireworks/charcoal_tests.html

Have you happened to do any research on TLUD ( Top Load Up Draft ) charcoal cooking? It's a little easier and doesn't require as much source material since it cooks itself. I'd like to think it takes a lot of the variables for the most part out of cooking charcoal if even halfway tuned correctly.

As Mixer shared add additional lift is probably your best option currently with your time frame. Then work on the issue when ya have more time.
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richardh08
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Re: Lift charge not working well under 3"

Post by richardh08 »

That’s good advice.

Your BP looks to perform satisfactorily in terms of how fast it burns, but it is difficult to be sure from a simple burn test of a small amount of powder. A comparison with BP made with one of Ken’s charcoals ought to settle the question.

I don’t think that attempting to provide more confinement of the lift powder itself is going to help much; the essential confinement is that between the mortar and the shell. Part of the problem could be that your shells are perhaps a little loose in their fit to the mortar. I tend to have that issue myself, but find that adding a little more lift solves the problem. I know my BP works well, but I rarely use less than 10% of the shell’s weight on a 3 inch shell – and frequently use quite a bit more than that if I want to be sure that it reaches a good height.

There’s no law that says you have to use a specific amount of lift. It doesn’t matter if you end up using more than someone else does, as long as you get the effect you want.
Even when I'm wrong, I'm convincing.
Redbullzuiper
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Re: Lift charge not working well under 3"

Post by Redbullzuiper »

@Boophoenix
That site is indeed a very informative site. I use it alot for information. I didn't use it back then, when making my own charcoal.
I see some critical information I didnt follow. Like the temperature.

@Richard08
I look forward to recieve Ken's charcoal. So I can compare it.

My shells are pretty lose, true. I think another fix for this problem will be to add an disk on top of the shell. Like I do in cakes. Or maybe just put
an old newspaper tightly on top of it in the mortar. I think this is a good idea to try this evening.

As for more lift powder. I allways have the feeling that adding more lift powder only decreases its performance/efficiency.

If I use, lets say 10 gram of lift powder, and increase it to 30 grams. It looks like it doesn't really improve the lift power, but only burns slower.
I think its caused because I put the fust at the top of the black powder. I think by drilling a hole in the bottom and attach the fuse trough the bottom
of the coffee cup will fix this problem. Im going to try that this evening.

I made some Vineyard BP yesterday. Very curious how it will perform, comparing to my willow. Didn't add dextrin this time.
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Lloyd
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Re: Lift charge not working well under 3"

Post by Lloyd »

"My shells are pretty lose, true. I think another fix for this problem will be to add an disk on top of the shell. Like I do in cakes. Or maybe just put
an old newspaper tightly on top of it in the mortar. I think this is a good idea to try this evening."
------------------

That won't gain you much - if anything - unless your guns are very short compared to their calibre. A better approach would be to place a tight-fitting disk over the lift powder (a sabot), and place the shell on top of that disk.

It is ordinarily done to make a small hole in the center of the disk, put the shell's time fuse through the hole, then secure the two lightly or put another disk over the shell in order to keep the shell from pulling out from the sabot's hole. The top disk won't contribute to the lift force significantly, but is only there to maintain the relationships of the parts until the shell is fired.

LLoyd
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sambo
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Re: Lift charge not working well under 3"

Post by sambo »

I actually agree with Richard, if you're unable to gain sufficient lift by increasing your BP charge then I'd suggest it's not your BP at all and something else. As Lloyd says - what is the length of your Mortar? You may have already included it in the thread but I couldn't find it at a quick glance - is it unusually short ?
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Boophoenix
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Re: Lift charge not working well under 3"

Post by Boophoenix »

Red, I'd like to complement you on taking our input and trying to reply to each. That's a little rare these days it seems.

Sambo, length was discussed and answered and seemed about appropriate I do believe. I believe the answer was around 50cm. So I'd look to Richard's reply that fit might be some issue since more lift isn't helping much. Although that was answered as well 3-5cm I believe was the reply.

There is one more option that will take some of the processing variables of granulation out of your BP if you have the tool to do it ( a comet pump, preferably a decent sized one ). Pressing and corning your powder. Ok, this will slow it's performance compared to properly granulated powder, but we've not truely established that granulating process doesn't have a flaw ( no offense meant ). It is the best way to compare performance between powders because it removes some of the variables of process granulating.


Temp is often over looked in hobbiest charcoal making. The best info I've found on that are from a few old books and some military articles that were shared with me. I have grand hopes of a lengthy and informative charcoal research project. I planned to do tests with some things beyond my capacity to achieve on my own so hit some snags in the start up process. Not wanting to back track I've kept the project one hold until I get all the test procedures in order, but may end up having to delete a few to move forward.

If memory serves me correctly a good base line for cooking charcoal for pyro use seemed to be around 750F ( 399C ). I haven't cooked any in a while now, but one of my early batches curiosity got me and I used an infrared laser temp gun and my TLUD showed to be around 800F at the bell and at the flame front.

Ken and Richard work on some charcoal tests that they submitted to AFN that I believe may be linked here in an AFN thread.
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Re: Lift charge not working well under 3"

Post by Mixer »

Although that was answered as well 3-5cm I believe was the reply.

That would be mm Boo.

I know - i`m a bit pedantic :roll: :lol:
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Re: Lift charge not working well under 3"

Post by Mixer »

If Reds guess of 3-5mm shell clearance is correct - then it falls within the generally accepted 20% of the cross-sectional area of the mortar - which leads us back to the BP - especially as he says adding more lift doesn`t increase the shell height.
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Boophoenix
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Re: Lift charge not working well under 3"

Post by Boophoenix »

Thanks for the correction mixer.

This is a little of a baffling issue isn't it. Which is why a suggested pressing and corning that should take everything but the supply variables out of the equation. Provided proper pressing forces can be achieved ( I left that out in required things previously ).

I made some early BP that exhibited some of these traits. I didn't however test to see if more helped any. The cause of my problem was a drying issue. It was the only variable between batches in that run as all the supplies were the same and just days apart nothing else I could foresee could have been the issue.
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Lloyd
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Re: Lift charge not working well under 3"

Post by Lloyd »

"If Reds guess of 3-5mm shell clearance is correct - then it falls within the generally accepted 20% of the cross-sectional area of the mortar - which leads us back to the BP - especially as he says adding more lift doesn`t increase the shell height."
--------------
In almost all cases, when adding additional lift does not increase a shell's height, it's the result of the powder burning too slowly.

Remember that initially the contents of the mortar are at atmospheric pressure, and unless the powder burns fast-enough to raise the mortar pressure high-enough for explosive burning of the powder, all that happens is that the low pressure 'pushes' all the contents out. With powder of that character, all you get when you add more powder is more powder burning outside the gun.

It's a common and well-defined problem. Any powder used for lift should burn with a decided "whoomp", even when in an uncontained pile. If it does not, you must either increase its burn rate, or put the slower powder in a 'shot', so that it explodes more-or-less like a BP salute under the shell.

That's the way the Maltese lift their shells, even with marginal grape vine charcoal powders.

Lloyd
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Redbullzuiper
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Re: Lift charge not working well under 3"

Post by Redbullzuiper »

@Lloyd
I tried to put a disk on the BP and on top of the shell. The diameter is pretty big for a disk. However, I had no success. It didnt really help much.

@sambo
I measured the tube and its 50cm long.

@Boophoenix
Thanks, for the complement. And yes the lose space around the shell is around 5mm. I do have a comet pump. The biggest I have is 8mm. I don't make any shells bigger than 4". To expensive for a small hobbyist like me.

@Lloyd,
"or put the slower powder in a 'shot'". This might be an excellent idea.
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Boophoenix
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Re: Lift charge not working well under 3"

Post by Boophoenix »

8mm pump is a little small to be very productive I'd suspect but for a test or two it might narrow the issue down.

If you have a little larger screen than a 10mesh you could try granulating a small amount with almost pure alcohol. Keeping maybe 20 - 30 percent water to help dissolve the nitrate a little. I've not personally had much luck with that method in a couple of tries, but others have good luck that way.

10 mesh is a little small for granulating BP and slow. At least it seemed so to me before I got some larger screens.
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Lloyd
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Re: Lift charge not working well under 3"

Post by Lloyd »

"@Lloyd
I tried to put a disk on the BP and on top of the shell. The diameter is pretty big for a disk. However, I had no success. It didnt really help much."
------------------
3" is hardly too big for a disk! We routinely use cardboard 'lift disks' in 4" products.

Unless the disk is tight enough to be a HARD 'force fit' in the gun AND is thick enough to resist 'teetering' sideways, it won't help at all.

The disk must STRONGLY SEAL the powder in its own little 'private room', not merely sit atop the powder.

When done right, this method is almost as effective as building a shot. Many Chinese consumer fireworks use this technique to obtain usable lift force from poor powder.

Lloyd
"Pyro for Fun and Profit for More Than Sixty Years"
Redbullzuiper
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Re: Lift charge not working well under 3"

Post by Redbullzuiper »

3" is hardly too big for a disk! We routinely use cardboard 'lift disks' in 4" products.
For my disks it is. Because the biggest disks I can currently make are just 2mm thick. But yes, it will work. I just need some thicker disks.

Anyway, I confined my lift charge well now and it lifts it now to an acceptable height.
Im looking forward to show you guys the video's comming Wednesdag or Thursday.

Thanks for all the help guys!
Mixer
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Re: Lift charge not working well under 3"

Post by Mixer »

All you need to do is laminate a few together - that is how commercial discs are made.
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Boophoenix
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Re: Lift charge not working well under 3"

Post by Boophoenix »

Congrats Red. Look forward to the video.
oliverbrown
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Re: Lift charge not working well under 3"

Post by oliverbrown »

Red, can you confirm you are still using 10% lift please and share how you confined the lift so anyone reading can see a working conclusion.
Great to hear you can now get them up nice and high, looking forward to the vid!
Redbullzuiper
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Re: Lift charge not working well under 3"

Post by Redbullzuiper »

Will create a new topic with photos while building and the finished products with videos.

Will fully explain which comps etc I used. Will post the link to the topic here.
Redbullzuiper
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Re: Lift charge not working well under 3"

Post by Redbullzuiper »

Ok guys, here you go

viewtopic.php?f=9&t=1299
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