Science/Engineering/Technical forums

I always liked hairspray and a lighter. You just can't get Adorn these days, so I used WD-40 the last time. Damn, I wish it could have been Tannerite...

Ah yes. Over the years, other pyrotechically minded friends and I have use a number of fire based tools of this, a little riskier but lots of fun.
Never did get around to hairspray, we always used for example, starting fluid. And at least at one time there were two interesting variations of it - one that made a fine mist, one that was more squirt-gun like, you could write your name on the lawn...

Quickly transcended by what you get if you simply have an old-style POL propane tank and a bit of hose to aim your flamethrower with - and be back far enough from where the flame front begins to avoid being burned by the radiant heat alone - we're talking 30 foot long flames here, that are 6 feet in diameter, if you want. Hair-curling, literally.

The last rig I made for an overhead situation like this was a small slotted chamber on the end of a 12' 2x4, with electrical ignition for the half ounce of black powder in it - slot pointed up. Use the stick to position it near the nest, fire it. They don't do well with wings burned off...Any remainder don't like the sulfur smell.

And a few other similar tricks.

Obviously, you can't do these tricks in an urban area, but if it's your stuff, and you're where you won't bother anyone or put them at risk, they're quite entertaining.
And what little politics I put out there involve the question "why must one size fit all"? I understand why it's fine for me to do that kind of thing "out here" and very not a good idea in say, NYC. Why can't the law understand this very simple idea?

Quote from Air America:
If I want to shoot lizards on my private miniature golf course at night, why would I annoy the neighbors?

For ariel nests, I just use Raid wasp and hornet killer. Very effective and I don't risk burning the house down.

6 of one...Gotta count the fun in the total score.
I've used "Hot Shot Wasp and Hornet" spray and it's pretty amazing - stuff drops in mid-wiggle. Works great on huge spiders too.

Sadly, I discovered if I get any on me, I'm up for a nasty bout of anaphylactic shock... To say the least, that's not fun. I have no idea how long it sticks around but
after that, I carefully de-toxed the area it had been and put the can away. I'd know to be more careful next time of course, but...it's more fun to make a blinding flash sometimes.

For the deafening report aspect, I tossed a couple grams of KCLO4::Al in a .223 case into the hole with a fuse in it and...there are no more stragglers.
For reference, a black cat firecracker has 25-50mg or this in it. This is not a bang you could do in a town...without gathering unwanted attention.

I still haven't done squat to the aerial one. It looks like the cool is slowing them way down and their numbers are also down. I don't think these guys can live without something around the comb.
I'm guessing they lost their queen, so it'll probably take care of itself. They don't seem to mind me using the door...

Oh, yes. Potassium perchlorate is fun, but watch your fingers...

In high school, my chemistry teacher foolishly gave me keys to the stockroom. I combined, very judiciously, KClO4, red phosphorus, and sugar. The class idiot grabbed the vial from my hand when he saw me being cautious with it, said "Ready, this won't blow up!"

The others in the class backed away from the idiot when they saw my face go white. Robby walked over to the window (2nd floor), opened it, and threw the vial to the sidewalk below. Burned his eyebrows off from the blast, and never doubted me again.

The sidewalk had a small crater in it. The librarian pulled the fire alarm, thought Cuba had launched the missiles, so we all went outside for an hour. Later, the principal, who lived across the street from our house and knew me, came over to ask me to please not do that any more.

Today, I'd be jailed for terrorism.

Yeah, today is pretty weird. If we'd had today's weirdness, I'd have been taken from my parents because they allowed me to free range, even bike to the next town with my buddies to go to the electronics mil surplus store...or go to the woods to "test energetic devices" of which we made many - and no blood, no foul, though a couple times people heard things and now and then called authorities over it. We were, of course, long gone by the time anyone showed up. Heck, today kids are taken because they got a needed spanking. No wonder we have some many brats coming up. I'm grateful I got "reminded" when I got really out of line! Out here in the real world, there are more severe consequences for bad acts, and it seems good to me to teach kids young that they're real and can't be whined away.

Even today, I have my own personal FBI "weapons of mass destruction" guy - and that's over the fusor stuff (! fame has its issues), the deuterium, and any radioactives. Luckily, he's a good guy, we touch base now and then. People have sent me some weird and dangerous stuff that I don't want, and he's helped it find an approved home, for which I'm grateful. He is apparently one of the 10% of government workers who try very hard to make up for the rest.

I stopped fooling with P in high school after a fairly nasty accident that happened at a friend's house. He and his dad worked at a chemical company, and we wanted to make a show-off smoke bomb for the company picnic. My friend's lab was well stocked, and of course we decided on P as the best smoke producer, but it was much too slow, so we tried various oxidizers....and wound up with potassium chlorate (not per). Well..after gently mixing the two and testing a little - it was great - we went to the next room to wash up. Whereupon the mix exploded spontaneously, blowing all the glass out of the door between the rooms (garage and washroom) which then embedded itself in our hides. My friend had few-gram test samples on his bench of various HE...which took part in the blast.
Needless to say, the parental units were very upset (there was also damage to a new car in the driveway)..and we were forbidden to hang out together (like...it's amazing what parents think sometimes, as if). But chlorate is something I'm super careful about, and just don't even get in the room with P - red or otherwise.

Flash powder won't go with the drop test - hit it with a hammer on an anvil and all you get is a sintered mass. Where other things definitely go bang quite nicely. It's much numb-er than black powder, which is numb-er than TNT, guncotton or smokeless powder (double or single-base). Or of course any primary energetic.

For reasons that should be obvious, I decided not to have a chemistry forum up here, as it always turns to energetics and attracts teeny-bombers and other undesirables. That keeps my FBI associate happier. As well as me. Having escaped with all my fingers and such (which actually was a good argument with some law enforcement types once) - I don't want to irresponsibly propagate some sorts of info to those with less safety discipline. It's the same type of self-discipline the gun guys around here use - your own "background check" on someone is far more severe than the government one if someone wants to buy a gun from you. Maybe it's different in the city where there's anonymity and what not, but around here, you can't even buy a gun at a gun store unless you are known to be a good guy. Works for me. Think how you'd feel if you provided what turned out to be a murder weapon. That's not something I want to go through.

"I stopped fooling with P in high school..."

I assume that P = phosphorous

Geeze. In Vietnam we had grenades filled with WP (white phosphorus). Nasty scary stuff. Burns spontaneously in air. Get some on you and it is a task to get it to stop burning. No one ever wants to be in that situation.

Could that be what you had?

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I also had a few dangerous interactions with chemistry in my youth. I was a bit too young for HS Chem class but I bought a book.
Some acids weren't too hard to get but the critical HNO3 for big boom stuff was not easy. So reading the book I made my own
chemical equation and decided KNO3 + HCl --> HNO3 + KCl, logical, right.

My friend had been allowed to set up a lab in the end of his garage. I was a key player in what we should do.
So some pool acid HCl in a flask with some KNO3 and some heat. A condenser of some sort for the output. After a bit, a yellow gas/vapor coming off but not condensing. Chlorine! Evacuate the garage.

Later I read the chapter about halogens and making chlorine by mixing HCl with a strong oxidant.

Many other stories of dangerous ideas or near death experiences available.
Oh well. Still here.

Yes, it was phosphorus (P). That stuff just wants to be on fire, and KClO3 wants to give off O, so...A mix of chlorate and sulfur is very shock sensitive and sometimes goes off spontaneously as well.
It's very rare to see those together in fireworks mixes, which is the main place anyone uses chlorate at all. Perchlorate has a much higher decomposition temperature and while having more oxygen is otherwise a lot tamer. The high temperature required works out nicely with aluminum since that also has a high burning temperature.
I have to thank Tenney Davis for writing "The Chemistry of powder and explosives" for still having my fingers and eyes...it's a little hard to find that book these days, but it's very authoritative.

That's a slick way to make a lot of chlorine...perhaps I'll try that to kill the fungus that is trying to eat the wood in my crawlspace.

Whilst surfing around, I saw this video, and at the time I linked here, there's a picture of...our standard counter. We sold a few of those, and now I'm wondering which customer is that guy, or if someone resold one.

https://youtu.be/ZO5IZz9NgJA?t=939

Haven't logged in for a bit, but all is well, just busy.
I've been lashing up and testing various pieces of the new setup, with the usual fits and starts, but it's coming along.
In between doing the usual homestead maintenance - things fail with the onset of winter and the increased beating the energy and heat systems take. Nothing abnormal, just a pain that eats time.

I'm doing some new data aq for the new setup - bad weather == good time for coding and kludging. This one might be general purpose enough to be something others could duplicate and use themselves. It's got the feature set I had before, but slicker, more A/D and many more counters as some frequency sensitive stuff is on the table here, is cheaper to build...lots better in many ways.

I've started putting some of my code up on github. I'm trying to put up any stuff I have that's decently organized, standalone, and mature, as I run across it or it hits that state. Yet another off-site backup. https://github.com/dcfusor is the place.

More soon, a lot of stuff is 80% done, but it's not done till it's done. The new HV power supply is a beast. Kind of on the stiff side, and I may have to add some smarter current limiting....as when setting all this up and initially testing stuff, sometimes with a little too much gas or whatever, the fusor can really draw some current - and this thing can supply that to the point of very fast very intense heating/smoke/destruction.

Things are coming along at the homestead - various "oh, things only fail in bad weather, but are now fixed" stuff - boring, and exciting (to me, anyway) - I've been doing some interesting (to me) work on a new data acq system with a lot more capabilities for fusor2. It's kind of kept my head down and nose against the abrasives. Which is fine, since some good things are happening.
I found a way to get nearly hard (low jitter) timing out of a raspberry pi, at least for this application. The original demand was to allow serious synchronization of some slave nano clones, so as to get more channels of input, and have them all in absolute sync with one another - even if there was a little jitter in the timing, at least I'd preserve the info about cause and effect, and not have one drift a lot in relation to the other one. That would happen even with crystal oscillators, but with the built in RC ones in these LG8T clones - it's bad.

FWIW, along the way I found out that there is hardware on the pi, badly and rarely documented, to create real serious low jitter timing if you can figure out how to work it. But it's intended to be used as clock generators for other uPs, I2S audio and the like - it won't go slow enough for this, and I didn't want to add a bunch of ttl dividers....

Well, I found a way that seems to give pretty reasonable results in pushing a pulse out of the pi on an IO pin that's within a few microseconds of perfect, at 100 millisecond intervals - just how perfect is probably going to be somewhat a function of other loads on the pi, but being able to get it that good on a preemptive opsys frankly amazes me. At least it seems to be that just about all the pre-emption that occurs happens *after* the front edge of the produced timing pulse, so it's don't-care. Whew. A version of that code went up on my github here: https://github.com/dcfusor/Timing_generator

Once I had hardware IO and this kind of figured out...I thought it might be good to have a few a/d channels right on the pi, using I2C and ADS1115 converters. Ok, I tried wiring pi - it works, but Gordon is taking it down, being frustrated by various life factors, and it doesn't support some of the things I want. Not really wanting to get totally into that ecosystem (it IS good for what it's good for), I decided to get down on the metal - to memory mapping and the somewhat luxury of some linux drivers - and go from there, which is where this is right now. I will publish this code, which is pretty cool, as soon as I've rubbed off some of the inevitable burrs. Since I've rewritten from scratch a few times to get the basic paradigm right, might as well make it purty and "production grade" before turning it loos on the world.

So the net thing will have 2 nano slaves, with 4 a/d channels (with some DSP tricks to get a couple more bits resolution) and 2 counters each. One counter on each one has been tested up to 12 mhz, and the tests I want to do on the new rig are going to involve some RF and more automated control than on the big one downstairs, so...need to write it all down so once the parameter search turns up some goodness, I'll have the data to analyze, plot and share. Whew, there's a lot of handle turning to get there, but there IS progress.
This will also have 8 channels of 15 bit a/d directly on the pi, and a couple 12bit d/a converters to enable some automated tuning and testing. Anticipated is some stuff that can measure phase angles and time delays and get that into the system as well. I think this is way worth doing, and after all this work to get it really kind of right - and very general purpose, the resulting design and code will be something I think others will want to copy -
That's one heck of a data aq system, dirt cheap, with a lot of downstream analysis capabilities and data mining - all this is going into an onboard SQL database, with tables for each bit of hardware, and other tables that can allow code to know how to interpret the resulting numbers, analyze, label, plot and so on, and make it easy to specify new schemes for any changes in the hardware lashup.
After it's time to build a railroad, it might be time to build a beautiful one. This would be an attempt at the latter.

Hopefully I'll be able to pull out for air and post a bunch of this on the github and here - I'll have a much better blow by blow description when it's not changing so fast, and the needed documentation for anyone wanting to duplicate this. I'm doing this one on a raspberry pi 4, but to be honest, the system loads I'm seeng so far for data only are in the few percent range, so it'd probably work fine on an older one. I'll test that sort of thing a little down the road...it'd be nice to have it completely self contained, though for safety here I'm usually using a separate server to do the SQL database -that way if the fusor-proximate one gets fried, I don't lose data up to that point. There doesn't appear to be any other reason, though - this thing seems to be loafing with this load.