Jump to content
APC Forum

Let’s see your BP!


Richtee

Recommended Posts

The basics... show a line of your BP. The “white paper” test. It’s a right of passage into pyrodom to make a good black powder.

 

C’mon, impress us! :)

 

 

  • Like 1
Link to comment
Share on other sites

Ayite, I'll play!

 

My easy-ignite visco (bp in rubber cement ball--makes some flexible stuff!) seems to have jumped the shark, hah ha ha !!! Phone smells like BP smoke now!

 

Yup, premature esparkulation. In the still you can see the sparks jump before the fuse is even lit, hah ha.

 

Next frame you can still see the unburnt half of the line...

 

Eye protection!

post-22609-0-12879500-1651622586_thumb.jpg

post-22609-0-25921400-1651622787_thumb.jpg

Edited by SharkWhisperer
Link to comment
Share on other sites

Seems an effective ant-icide as well :D well done... (bow)

Edited by Richtee
Link to comment
Share on other sites

Seems an effective ant-icide as well :D well done... (bow)

there weren't many ants left to complain... :wacko: Probably would have been just fine with a row 1/4 that mass or less instead of "hmmm, that should burn pretty nicely; maybe just a little more to bury the fuse..."

 

You've been playing around with crackle-dipped visco. NC lacquer dries hard. Try some good ol Elmer's rubber cement--can make sheets of any thickness and comp that're completely flexible. Stuff sticks to everything until it starts really setting up, but uses only limited by imagination.

 

That dough ball on the end of my fuse was pretty large (hence the tons of sparks), but it was made like that for starting difficult comps (in this case a BaSO4-based mix), where the BP/rubber end would be in the comp and not be the end that you'd ignite first!

 

I started testing using rubber cement instead of NC lacquer to enhance the fake pyrogen as a dip for cheap Estes nichrome "starters" and for making custom electrical igniters for finned rocketry. Considered parlon in acetone originally as a carrier and I'm sure it'd work just fine, but why bother when you have cheap rubber cement laying about? Will carry pretty much any pyrogen that NC lacquer will, but has flexibility too (hard/brittle pyrogen dabs on bendy nichrome wire igniters are prone to cracking...). Haven't noted any rxns between rubber cement and solvents (MSDS only says heptane) vs perc and nitrate-based pyrogen comps, with or without metals (Al, MgAl, or B, +/-Ti). And even smokeless powder for NC has gone up in price a lot and supplies are in flux lately, like a lot of things. NC actually inhibits ignition if used as a coating atop faster burning igniter pyrogens--it burns like crap as a dense solid vs fluffy guncotton format. You know how slowly uncontained smokeless powder burns, and dissolved/dried NC is that much slower. No residue, though. Should see if I can dissolve some unpolymerized Viton powder into pre-made rubber cement (can't see why not) to enhance reactivity for ignition--starting out with a thicker mix would be a bonus anyways.

 

Need to do more testing regarding actual fuel value of the rubber in Elmer's etc in comparison to parlon (chlorinated rubber), for example, but so far rubber cement seems promising. If you stop that video early on, you can see that BP/rubber ball burns pretty cleanly, apart from the expected sparks and smoke that's probably BP; little residue left afterwards, though this wasn't really a good demonstration. Guessing it might leave a similar residue to parlon (at least some parlons...), which I've seen as a glowing orange skeletal afterburn in some star comps. And the cement's available everywhere for cheap. Again, though, it's messy to work with, at first--the heptane solvent (component of gasoline) evaporates much slower than acetone in NC, so patience is useful. Working time is increase, though, and that can be helpful sometimes.

 

Would be interesting to try to bind crackle stars with it--doubt the NC has much critical value to the smoulder/pop reactions of crackle/DEs and almost for sure the Chicoms are using phenolic or similar as a binder instead of NC in their cheap crackle comps. The rubber balls, when completely dry, have about the same "give" as a gumdrop, if that makes any sense, but it has shape memory. Shoot, probably little difference from regular old rubber stars bound with parlon except Elmer's has uncertain chlorine content (if any) for color enhancement...

Edited by SharkWhisperer
Link to comment
Share on other sites

damn. Now I got work to do :D thanks Shark. Yes..I mean that. Prolly have some use in rising effects as I mentioned "gorilla glue” a few years back. Nice BP once again...

Edited by Richtee
Link to comment
Share on other sites

damn. Now I got work to do :D thanks Shark. Yes..I mean that. Prolly have some use in rising effects as I mentioned "gorilla glue” a few years back. Nice BP once again...

Cool beans--fun stuff to test new ideas with! Will have to search for old Gorilla Glue threads. With fuse so stupid expensive lately, I could easily see some visco replacement consisting of a thin tube/slice of rubber impregnated with BP and quick-dipped in another coat of straight rubber for spark containment. Burn time regulated by BP content and coating... And who knows what kind of gerbs you could make with some ropes (or cones!) of crackle-infused rubber, hah ha. Yipes. Anyways, keep yer fingertips and eyeballs intact--that crackle gets jumpy!

 

Your BP's no slouch, either, and looks like it can do pretty much anything you asked of it that's pyro related. This batch is based on a big pile of weeping willow standing deadwood/branches that I stockpiled and turned to charcoal a few years ago that never fails to deliver. As hot or hotter than any paulownia, ERC, or alder I've used. I rate BP batches on a qualitative 1-10 scale for burn rate, both before granulating and after (usually gain 1, sometimes 1.5 points on the scale from wet granulating by my determination). That batch I'd rate at about a 9.5; which is pretty hot. I usually get, and am happy with, burn rates around 8.5-9.0 by my judgement. A batch rated 8 is "suitably hot" for most applications and the now rare 7s are destined for blackmatch or gerbs if no binder (though you can mill it down again anyways if you wanted). This was sized -20+40 for experimenting and lift for small (3/4"-1.75") mini-mortars, mines, and starguns (crackle mines are a hoot!) and bursting small items, so somewhere around 3Fg sized (need to refer to a table). Maybe 3.5Fg, hah ha. I size pretty tight ranges for different applications. Works ok for me.

 

Will look forward to seeing what your creative instincts come up with!

Link to comment
Share on other sites

Although not in a line, it's mine !!

 

  • Like 1
Link to comment
Share on other sites

Although not in a line, it's mine !!

 

Oh yeah! That BP will do most anything you ask of it, except making breakfast and giving out foot rubs! Very nice!

 

What kind of wood/charcoal do you use for BP in India? From the shape of the larger fragments, it looks pressed/pucked/corned and not so much like granulate--is this correct?

 

That's some very excellent BP!

 

Edited by SharkWhisperer
Link to comment
Share on other sites

 

No dextrin

That'll do the trick! What kind of charcoal are you using?

 

If that doesn't eclipse commercial Fg-grade BP gram-for-gram, then it comes pretty damned close. But Scheutzen/Goex/Swiss don't go for max speed because they'd never be able to reliably reproduce it--they go for a very reproducible, very predictable moderately-high burn rate in the face of sometimes-changing charcoal availability and batch-to-batch variation (although their batches are huge).

 

If an 8-12" line of your BP burns fast enough that the naked eye can't see the progression down the line, that's pretty quick and sufficient for pretty much any pyro application.

Link to comment
Share on other sites

Bengal and U- Nice work, fellas :)

 

Maybe now some of the new folks will be motivated to get that BP right before venturing into the Vitamin F. Not much skill in that after all...

  • Like 1
Link to comment
Share on other sites

Here it's is. BP and lift test.

Though i used incense stick to light it but i forgot that i am holding mobile near to test. Burnt few hairs in fingers and my mobile smells like BP. But ultimately happy to see the results

  • Like 1
Link to comment
Share on other sites

Burnt few hairs in fingers and my mobile smells like BP. But ultimately happy to see the results

I sometimes notice the awful smell of burnt hair along with the sweet smell of burnt BP :D

Link to comment
Share on other sites

Oh yeah! That BP will do most anything you ask of it, except making breakfast and giving out foot rubs! Very nice!

 

What kind of wood/charcoal do you use for BP in India? From the shape of the larger fragments, it looks pressed/pucked/corned and not so much like granulate--is this correct?

 

That's some very excellent BP!

 

Thanks, and you're right!! It was corned bp.

Here, in West Bengal (a state of India) we are, the hobbyists usually prefer to use Jujube (Ziziphus jujuba), Castor Plant (Ricinus communis), Indian Drumstick (Moringa oleifera), Babul (Gum Arabic Tree) for our bp. I don’t have idea about other parts of India. Deepak lives in the southern part of India and he can tell us what they do.

Link to comment
Share on other sites

In south of India as for hobby, i used to make charcoal for BP from a fast growing species sembam tree(biological name unknown- native to South India), subabul tree (Leucaena leucocephala). Yet to try Indian Drumstick (Moringa oleifera) & castor plant which is available readily. I have used charcoal made from teak, having longer hanging time. I have seen people using egg plant & Cotton plant stem to make charcoal for BP used for other purposes(any one have any idea on this overseas ?). Edited by deepakpyro
Link to comment
Share on other sites

Hi Deepak,

I request you to post some photos of "sembam tree" both with close view and long shot.

Let's see if I can recognize it.

Link to comment
Share on other sites

The tree is Sesbania grandiflora(brown agathi) belongs to family of "Fabaceae". This called in different names in diff regions of our state itself. Its a fast growing tree and charcoal made out of it is porous and light weight. Edited by deepakpyro
  • Like 1
Link to comment
Share on other sites

That'll do the trick! What kind of charcoal are you using?

 

If that doesn't eclipse commercial Fg-grade BP gram-for-gram, then it comes pretty damned close. But Scheutzen/Goex/Swiss don't go for max speed because they'd never be able to reliably reproduce it--they go for a very reproducible, very predictable moderately-high burn rate in the face of sometimes-changing charcoal availability and batch-to-batch variation (although their batches are huge).

 

If an 8-12" line of your BP burns fast enough that the naked eye can't see the progression down the line, that's pretty quick and sufficient for pretty much any pyro application.

Thanks, that is weeping willow that I cut a few years ago. It is the solid trunk not branches. Milled for three and a half hours which is my standard length of time. I'm sure I could go longer but I think it's good enough. Edited by Uarbor
Link to comment
Share on other sites

Thanks, that is weeping willow that I cut a few years ago. It is the solid trunk not branches. Milled for three and a half hours which is my standard length of time. I'm sure I could go longer but I think it's good enough.

 

Looks like a perfectly good burn rate for any fireworking task, lift/burst included. Yeah, for lift/burst and nozzleless rockets, faster BP is just easier to work with. Low or lame bursts are not good. It's painful to watch videos of newer folks launching first shells that barely launch out of the barrel. But super-fast BP isn't always necessary, and even moderately decent BP will work for most applications. And purposefully slower BP is needed for nozzled rockets (e.g., 65:25:10), gerbs/fountains, and as a foundation for many charcoal star comps. Blackmatch is essential and can be made from slow(er) BP or from super hot BP. Personal preference is to aim for as BP that burns as fast as I can reasonably (and easily) get it for lift/burst, except for targeted purposes like nozzled rockets. And it's fun to watch your BP shoot a shell higher than commercial BP, gram-for-gram, at least once. Though I have a preference for homemade willow and ERC coals, that's mostly from habit and location/availability--others have demonstrated very fast BP made woods I don't see too often in my locale (e.g., eucalyptus in commercial bbq coal chunks (Brazil) and pecan (Texas; probably easy to find pecan bbq charcoal, too). And now at least two compadres from India have identified trees/wood for charcoal that for sure are completely new to many fireworkers elsewhere in the world--that's really cool. I've used bbq charcoal (Cowboy brand, though gotta read the label to see which country it came from, and guess the wood from there...) that made decent BP. Serviceable, at least. If it's plant-based, somebody somewhere probably tried to retort it and mill it to BP at some point. When I finally got ahold of some "legendary" paulownia coal from fireworkcharcoal.com, it was very good but not as super-hot as I expected... And now paulownia growing wild in a lot of places if you can recognize it--I'd probably be stumbling around the pastures and woods with a picture book of trees! I was going to retort some tomato stems I dried out just for investigative pyro BP fun, but they somehow got tossed before I got around to it... And that commercial airfloat charcoal that pyro vendors should be embarrassed to sell in "BP" kits is absolutely crap for making fast BP (and a huge frustrating turn-off for new folks wondering what they did wrong--nothing!) but is great for making many stars, gerbs, primes, and slower match!

 

Some on here report excellent BP outcomes with just screen-mixing, but I need a mill myself to get maximum speed from my BP. Even a cheapo HF hobby mill will do the trick, though not quite as cheap as pre-pandemic and since they stopped offering the 20% off coupons. Or make a safe (non-sparking) one yourself for even less. But basic fireworking requires at least a mill and set of decent screens, at minimum. Used wooden tools for years before buying my first commercial spindles & rammers, with good results, too. My old oak rammers still see use compacting gerbs. A lathe or friend with a metal shop would be handy.

 

Anyways, strayed off the point, but weeping willow has worked very well for me, too! And simple to identify without being an arborist/lumberjack/woodworker. Some report black willow is faster but there are many many willow types (and pine, and cedar, and sembam, and...) to try.

Edited by SharkWhisperer
  • Like 1
Link to comment
Share on other sites

Too much wind today to do my test.

There will be other days, my friend. Keep the faith!

Link to comment
Share on other sites

Had better conditions today.

 

Riced. Huh. Impressive... A bit drossy, but I’d expect that outta screened. Gonna have to scrape yer mortar tubes more often is all.

Edited by Richtee
Link to comment
Share on other sites

  • 5 months later...

Thanks, and you're right!! It was corned bp.

Here, in West Bengal (a state of India) we are, the hobbyists usually prefer to use Jujube (Ziziphus jujuba), Castor Plant (Ricinus communis), Indian Drumstick (Moringa oleifera), Babul (Gum Arabic Tree) for our bp. I dont have idea about other parts of India. Deepak lives in the southern part of India and he can tell us what they do.

In sivakasi they use Gum arabic (Babhul tree) charcoal...two varities are available single filter(150 to 200 mesh ) and double filter (400 mesh). 400 mesh for bp quick match...rest for delay tube priming stars etc.
Link to comment
Share on other sites

  • 5 weeks later...
×
×
  • Create New...