A few weeks ago, a video went viral on social media that depicted a rather unsavory individual receiving what could be described as a “percussive reminder” of social norms courtesy of a bystander armed with a can of Twisted Tea. The video served as inspiration for many a meme, but perhaps none more technically intricate than this air cannon that launches 24 ounces of hard iced tea at better than 100 miles per hour built by [Greg Bejtlich].
Technically we’re looking at two different hacks here. The first is the pneumatic launcher put together using a low-cost eBay tire bead seater. These tools are designed to unleash a large volume of air into a tire so it can be properly seated onto the rim, but it doesn’t take much more than a few pieces of PVC pipe from the hardware store to turn it into an impromptu mortar. It’s even got a convenient trigger and a handle to help control the recoil. Though as you can see in the video after the break, it still ends up being a bit too energetic for [Greg] to keep a grip on.
For the projectiles, [Greg] has 3D printed a nose cone and tail fin that snap onto the 24 oz cans in hopes of making them more aerodynamically stable. The slow motion video seems to indicate they aren’t terribly effective, but they certainly look impressive. Spring-loaded control surfaces that deploy after the can leaves the muzzle could be the answer, though at some point you have to ask yourself how far you’re willing to go for an Internet meme.
It probably goes without saying that you definitely shouldn’t try firing cans of alcoholic iced tea off in your backyard. But the launcher itself might be useful for lofting antennas or hurling the occasional potato.
https://www.youtube.com/watch?v=dFopqMB3g90
[Thanks to Eric for the tip.]
At a guesstimate by the angle the air will come off the back of the can, I think that only about the top quarter inch of the fins are effective. So if total length an issue, I’d lose it in the nose, make it shorter and blunter, and add a more gradual transition behind the can and longer fins.
Base bleed projectile
https://en.wikipedia.org/wiki/Base_bleed
I agree, the back fins are probably not doing anything.
And with the nose, that can be way shorter. I’ve launched model rocket engines bare, and they shoot incredibly straight even with no nose cone or fins.
I´d say: first freeze that can in a vertical position
I wonder how much stability would be improved by angling the fins to force the can to spin
Dear Hackaday. You’re supposed to lead the way. Please stop it with the oz and miles. Thank you, the rest of the world.
Dear EU, please stop oppressing people who want to get the job done without bureaucracy. Metric system is a failed idea, useful maybe only for physics experiments, not much more. It’s much more intuitive to divide 1 inch into four 1/4 inch parts than it is to divide 25 into some decimal point scoobydoo.
Its literally a divide by 10 system. get over yourself. it is not that hard.
No problem, keep counting in sub-units of human appendices and buckets of grain while the rest of the world moves on.
Can you tell one single country that moved AWAY from metric system ?
In general, I’m in favor of moving to the metric system as well, but don’t make it out to be a measuring system based on some idealized quantity. “Let’s base our system on a swinging pendulum from some random clock tower!” “I know, let’s base it on some division of the distance between the equator and the north pole!” “Wait, let’s base it on some random number of wavelengths of krypton!”
The United States of America, the richest and most powerful nation in history. Congress approved the metric system in1888, but did not make it mandar
Tory because of the retooling costs to build the cover wagons hub nuts. The metric system is great for computers and people with poor math skills that can’t be competent enough to work with fractions. Why is the day divided by 24, the hour and minute divided by 60? As well as angles and music notes in 8ths? The true measurements should be done in natural units and not man created; u less you are not planning to leave your cave.
It’s not the EU – it’s almost every country in the world. The whole world uses the SI system, with 3 third world countries excepted – Myanmar, Liberia, and the United States…
That’s 192 countries to 3 who manage just fine dividing by 10.
https://en.wikipedia.org/wiki/Metric_system#International_System_of_Units
Yet Britain still sells beer in pints and liquor in drams and gills. People are weighed in stone and horses are measured in hands. Don’t get me started on the firkin. What’s a jeroboam in metric?
Then we can move on to how we define the limits of a country’s territorial waters.
You don’t like 24 ounces? I say .68 liters just sounds silly
And a potato will kill you just as dead as a can of iced tea.
680mL – not that hard.
What’s a litre (note the spelling) in ye olde measures, 549923/2500000ths of a Gallon? Wow, so easy…
A feature of the SI system is that it’s scalable – you don’t need fractions of the base unit. Here’s a guide for the older generation. https://en.wikipedia.org/wiki/Metric_prefix
>A feature of the SI system is that it’s scalable
And yet none of the units are directly useful – like a cup or a gallon, a teaspoon or a foot. When you measure something in metric, it’s never ones and twos, or halves and quarters, but 335 ml or 1.76 m which pushes the mental arithmetic on simple things to greater precision and makes it more cumbersome.
A “four by eight” sheet is 1200 x 2400 mm in metric countries. How many sheets do you need to cover up a wall? Well, if the wall is 4 meters long, and one sheet is 1.2 meters… 4.0 divided by 1.2 is… let’s see, three times 1.2 is 3.6, and you have 0.4 meters still to go, so 0.4 divided by 1.2 is the same as 4/12 which is 0.333… so 3.33 sheets. Easy?
Contrast to covering a wall 14 feet long with 4’x8′ sheets. Well it’s obviously 3½ sheets because 3 times 4 feet is 12 ft and you have 2 feet left to go, so half a sheet. It’s like this unit of measurement was made for the purpose of measuring objects at a human scale, rather than metric units which are either too coarse or too fine for the job.
>680mL – not that hard.
Say it out loud.
“Six hundred and eighty milliliters.”
vs.
“Twenty four ounces.”
Let’s sing: “I would walk eight hundred kilometers, and I would walk eight hundred kilometers more, just to be the man who walked eight hundred kilometers to….”
It’s like they say: “Give two and a half centimeters, and they will take sixteen hundred meters.”
The problem isn’t the metric system, its the decimal system.
Basing everything off of the units that make up our counting system is super useful for a lot of reason. However, other systems of measurement make fractional amounts so much easier. If not for that one hitch, the system would appeal to everyone.
The issue is not that metric is a bad idea, it’s just that a half/quarter/eighth of 10 is not a very nice number. If we used base 12 or base 16, the metric system would be perfectly useful for all situations. Base 16 being better in my opinion because it reflects fractions when we go into integers (i.e. 1/16, 1/8, 1/4, 1/2, 1, 2, 4, 8, 16).
Soooo – your objection to the metric system is that it doesn’t work neatly when *you* try to force it to quantify *your* nonsensical measurements?
I’m perfectly happy buying my milk, flour, etc in nice round quantities of 1 litre & 1kg respectively.
The only reason sheets of plywood are 1220x2440mm is precisely because of other people’s refusal to modernise. The rest of the world would be delighted to throw off the deadweight of this medieval nonsense and change to buying sheets of whole numbers like 1×2 or 2×3 meters!
Your problem here is just that: your problem. It’s not a problem with the system.
I just want to stick in an additional penultimate line “Estimate quantities in metric or imperial” into this… https://en.wikipedia.org/wiki/Competent_man
Let’s stop picking arbitrary examples of “what is convenient in one system but not in the other” because all arguments until now are reversible.
> You don’t like 24 ounces? I say .68 liters just sounds silly
Silly indeed, but almost all beverage cans in the UK are 330ml (~1/3 liter) and wine bottle are 75cl (3/4 liter). US beverage cans are indeed 12 fl. oz (~355ml), but guess what? No matter where, they’re called ‘a can’. Packages around the globe are adjusted to hold round measurements.
Fun side note: most bottles that used to be 18 fl. oz in the US are now 16.9 fl oz. Same size as 500ml ones in the rest of the world.
Did I mention 12 US fluid ounces are ~355ml but 12 UK fluid ounces are ~340ml?
> A “four by eight” sheet is 1200 x 2400 mm in metric countries.
So, how many on a 6 meter wall? 6000/1200=5. For 4m you’ll need 2/3rd of that, but sheets are sold whole, so you’ll need 4 whole sheets for either a 14ft wall or a 4m wall.
But all jokes aside, a 4m wall is more likely to be 4m8cm (or 408cm) and the 14′ one will measure 14’2″ (168 inches). Both need to be measured twice so sheets can be cut once.
The thing everyone fails to mention is that in metric: 100cm is 1m and 1000m is 1km. Yet in imperial: 12″ in 1ft and 3ft in 1 yard, but 1760 yards in a mile?
Bonus in metric: 1cm³ is 1ml, so a volume of 10x10x10cm = 1000cm³ = 1L. It also requires 1 calorie of energy to heat 1ml of water 1°C, which is 1% between freezing at 0°C and boiling at 100°C.
In imperial: 1 inch³ is 5/9th fl oz, or 231 inch³ in a gallon. And although BTU is the preferred imperial heat energy measurement, which is a nice number for energy needed to heat 1 pound of water 1°F. 1°F is ~0.55% between freezing at 32°F and boiling at 212°F. Also, a pound of water is still a weird 27.68 inch³ or 15.34 fl oz.
Yeah, and the Fahrenheit scale has 1.8 times higher resolution than the Celsius scale. So smackaroo EU!
My cheap thermometer on the table has just an extra digit and 10 times the resolution. So where is the problem?
Precision, accuracy?
B^)
yeah, and i am 1.82 meters tall (not really, more like 1.95). the metric system lacks a realistic, human-size scale. a 4×8 ft. piece of plywood conveys more information about size and scale than one that is 1.22×2.44 meters. oh, and the imperial system has a convenient factor of 3 in it. i guess if the pound/foot/second system eventually dies at the feet of the kilogram/meter/second system, at least we will still have 360 degrees in a circle. who knows, that might go metric, too. would 100 or 1000 degrees be better? at least that would be easily divisible by 3. i don’t even want to think about metric time. 3.3 hours of sleep at night, 10 days a week, 10 months a year? let’s just use the light system, where 1 unit is a lightsecond. c x S == 1. all in favor, say ‘aye’. i’ve often thought having what we perceive as an absolute would be the best choice for a system of measure. that makes me 6.5x10E-9cS tall. that would be better than all the women in the world saying,”… and ‘this’ is 15 centimeters.”
i think i’ll re-think my dissertation topic. 120 pages and footnotes would be a piece of cake.
i’m sticking with my homie, FKO, on this one.
i hope i wasn’t too repetitive. or too much space. i love this argument.
If we’re changing things, can we start using Tau instead of Pi?
I don’t know, I haven’t read any reviews on the Raspberry Tau.
Does Micro Center sell them?
Wow you must be so smart and sophisticated.
If I am, then 94.7% of the world population is also smart and sophisticated, and by my book, that’s super good news!
What? No more articles from Australia?
But, we like Lewin.
It literally says 24 oz on the can.
So much discussion about trying to get 3 countries to switch to metric when the real priority should be getting everyone standardised on a mains power plug and mains voltage and frequency. There is a lot more work to do there! Perhaps take the base 10 lead and make everyone go 100V 100Hz?
I like the 100Hz idea, but lowering to 100V means I have to more than double up all the wiring in my house. Better to go the other way and standardize at 1000V ;)
(your insulation is still up to code, right?)
400 Hz needs smaller transformers!
Which is exactly why it’s used for aircraft power distribution
Electricians hate him, double the capacity of your household wiring with this one weird trick!
I think a fair amount of the instability in flight is due to the fluid shifting inside the can as the launch forces equalize. I don’t know that there would be a passive solution that would be completely effective, though [Nate]’s suggestion about spin would be worth a shot. If that wasn’t satisfactory, I’d try emptying the can and then filling it completely full with something that’s not going to shift in flight (concrete, expanding foam/great stuff, etc… depending on desired mass). As a “safety” measure, it might be fun to build-in a whistling chamber into the nosecone… the only thing more baffling than a highspeed can of twisted tea flying overhead is one that’s screaming like a mortar while doing so.
Freeze it first!
B^)
If you make light of criminal assault causing grievous bodily harm you should not complain if somebody inflicts in on you too. Making yourself judge, jury and executioner when interacting with mentally incompetent people, inebriated, drug affected and or mentally ill, does not make you funny, smart or meme worthy, it makes you a hypocritical sociopath. Seriously, grow up.
I think it reminds all of us that we’re not immune to social norms. Pretending otherwise gave us just this story.
The idiot literally told the guy to hit him, so he gave him permission. That’s no longer assault.
If the guy was out of his mind (as he clearly was) it is not informed consent, and it is debatable if it would ever be a lawful act under any circumstances.
Related project (which I’ve done with an air compressor and a solenoid intended for a yard watering system) is very rapidly inflating a large spooky creature at halloween. Person walking up to your front door sees something that looks like a bundle of rags and at the right distance is quite suddenly an upright creature with outstretched arms. It worked pretty well. (I developed this from a genius piece of artwork in NYC where people were taping garbage bags into humanoid forms and taping those to vents over subway systems, so when a subway went under and a big pulse of air came whistling up, the figure would leap up like those giant inflatable advertising dummies.) A rapid tire inflator should do an even better job.
(Don’t make it airtight: it’ll burst. Vent in the ends of the arms.)
I’m sorry but i just have to vent for a moment, here’s my summary of article and video:
– Some meme i dont know or care about (why is HaD reporting on memes? bring your kid to work day?)
– Some drink i dont know or care about (seriously tea with alcohol? that’s just dumb)
– Some unhealthy looking dude who i instantly dislike (using apple crap as a fashion item? or does he prefer poor audio quality for a crazy price? i certainly dont appreciate the terrible sound quality in his video)
– Plugging his tiktok videos that i REALLY dont care about (besides tiktok and its users being cringe & the platform vanishing within 2 years like all the other video & gif related social media, A VERTICAL VIDEO in 2021? my god man)
– The build is literally an off the shelf system with some pipe fittings added & it self destructs when you fire it? (im not usually one to ‘go there’, to each their own etc, but “why does this deserve an article?” was never more correct as in this situation)
– Whatever happened on tiktok, it already gave him a massive ego (“my tiktok is ‘so outrageous’ that i got a free 3d printer but i cant be arsed to actually show you or even say thanks to the company”) so he really didnt need HaD to give him exposure.
To summarize, my god HaD, have some self respect, or at the very least respect your readers, please dont give a podium to social media trash & dont try to ride the coattails of some dumbass meme, HaD is so much better then this, shame on you.
+1
Everything OK bud?
Nope, he got old. :-D
Darn, I hate when that happens.
Yeah im fine but i guess i did “get old”, sorta anyway, im nearing 40.
I hope you find the help you need.
Thanks and likewise :D
Well, I was the one that sent the tip in. So HERE is why it deserves an article:
I saw this video on Reddit. I don’t know about the meme, or tictok, twisted sister tea or any of that crap. I know how to watch a lazy/incomplete/incorrectly executed hack & extract the useful info – which is the bead blaster for cheap & it’s potential uses in backyard artillery games.
Then a week later I was bored & was going to check ebay just to see what these bead blaster things cost, other utubes that utilize it, etc.
I forgot where I saw it and looked on Hackaday first. Then found it on reddit. Then sent it to HAD since I looked for it there 1st and my text was “this has potential”.
Potential that HAD readers could be inspired by & maybe someday in the future a REALLY good hack using the bead blaster will be here to read.
The potential I imagine can only be realized by people seeing it, So I guess it’s OK if it pisses off 100 readers and inspires 1.
Yes actually, I made a mental note of that bit, the bead blaster being able to supply a large volume of somewhat pressurised air. Good thing to keep on file in case you want a T-shirt cannon, or rope thrower or something. I know there was something else I wanted similar type of whoosh for, but can’t think of it right this second. I know I was braining around making big ball valves, or adapting car throttle bodies or something.
Alright then, thanks for the input & didn’t mean to devalue your tip, that air canister could do some fun things :)
I hope that this ‘pisses off’ less users then you suggest by the way, because if those numbers are correct then posting this article was that much weirder :P (also for the record “i’m not pissed off, just disappointed”) Going by the replies i’ve gotten, i’m guessing only 1 in 8 readers are disappointed haha.
Yup. This would be great for a spudgun.
The posted video was a bit reckless with firing too close to the neighbor’s house, but even the “heavy can” idea would be fun if you do it out in the middle of nowhere.
What a sad life you must have. Please feel free to leave and never come back.
Couldn’t decide between these replies, so you get them all :D
My live is actually quite alright, but thanks for the concern
—-
Im not sure about you, but i dont keep HaD open 24/7, so technically i leave it several times a week, cool that you gave me permission though. Also if we’re talking about it in the sense of a user account, you might’ve noticed that (like you) im replying as guest, not sure how to leave when im not joined? :P
—-
“Something something social media generation making the most obvious reply for likes” while HaD doesnt actually have any social crap, nice job ;)
—-
Please feel free to ignore reactions if they dont line up with your opinion, telling me i have a sad life has no effect (or the opposite of what you want because it made me chuckle) & it certainly doesn’t make me do a 180 on the article, video or project in question.
Have a nice day :)
Where is the problem with tea with alcohol? Except if you live in a permanently hot climate, some tea with rum can be delicious on a cold winter day.
Now if you could launch it out of the smarter every day air cannon. Too bad it’s too big diametrically.
That’s what sabots are for
What I found, a 24oz can is around 87mm while a baseball is 74mm. I can’t imagine a sabot with a negative thickness :-)