That's obviously extremely lightweight for trebuchet payload, but for comparison, his projectile is approximately 62 grains so approximately twice as heavy as 30 grain high speed 22LR rounds. And approximately 1.5 times as heavy as 40 grain subsonic rounds.
1 gram is a little over 15 grains, and there are 7000 grains per (avoirdupois) pound.
I actually have a camera that can shoot that at high speed (1200fps), but i'm sure other people have better cameras these days, mine has very low resolution.
Which is a road trip to some place very empty in something like a 180º arc. Maybe 225º.
Further, you test in an enormous empty field, as he's doing.
But he also used an extremely lightweight ball projectile — a few grams of 3D printed plastic — because he was only interested in the launch speed. And he pointed it in a direction where there were no people for miles.
Into the ocean, I would hope
I really wonder just how effective this could be as a defense system .. the mind wanders with every update Tom makes .. I imagine an aiming/targetting system would make this an effective, easily replenished, low-resource weapon system for some applications. Attacking feral animals, perhaps?
How could an auto-loader work for this .. I'm sure there's a means.
Another thing that I keep thinking about, is whether this would be an effective way to launch seed-bombs, or deal with avalanche conditions on a mountain without requiring fire-arms training.
A truly fascinating bit of engineering. I hope to see it evolve into an effective delivery mechanism.
I should build something this weekend…
Could it be done reliably with traditional construction techniques (wood, treenails, lashings, minimal metal hardware)?
AFAIK these are innovations that were not explored historically. It would be interesting to see if they would have been viable. It seems like you could probably achieve a lot more downrange energy using the same amount of materials this way.
This is HN. The trip is the destination, bla bla.
Some of the features he used are pretty cool though, like varying the winding drum diameter to vary the delivered torque over the course of the weight drop.
You'd need trebuchet training instead, which is probably not better in the long run. I bet there's still lots of ways to kill/mangle yourself with one of these, especially once you've been around them long enough to get casual and sloppy.
Swiss solution: chuck some explosives out of a helicopter https://www.youtube.com/watch?v=H519qhLnRtM (start at 1:20)
(In the image at https://swisshelicopter.ch/de/aktuelles/721-lawinensprengen-... the explosive pack says "do not eat". I'm not reassured that we need this warning for people allowed to handle that.
Not sure what type of explosive that is but the rumour is that C4 when ingested gives a high similar to alcohol. Or at least that is what some troops believe.
“Amongst field troops in Vietnam it became common knowledge that ingestion of a small amount of C-4 would produce a ‘high’ similar to that of ethanol, and it is possible that this was the reason for this episode.” From the clinical description of a c4 poisoning case.
I helped design the "reloadable" part of a golf-ball shooter that used acetylene as the accelerant. I don't think it went supersonic, though. There's videos (embarassing ones) on youtube. He eventually designed one that can shoot full cans of monster energy hundreds of yards.
the reason i bring it up is we used to design and build pneumatic ones, that could send C and D batteries thousands of feet if you arced it right. that was with ~125psi, we always wanted to build out to 200+ psi, but instead went into accelerant-based cannons and he got a job doing machine drawing with autocad. the rest is history.
edit: https://nextcloud.projectftm.com/index.php/s/cobra5x we show off the part i designed, toward the end on the "reload" - he designed and built the entire thing.
He got an efficiency over 40% (if memory serves, I watched this video yesterday) -- I wonder between pumping and discharge how efficient a pneumatic system would be, but I can't imagine that it's higher.
But yeah, the fact that it's super cool looking - and sounding - is a key factor in my willingness to play with one too, one day. ;)
Thus a traditional trebuchet design cannot reach that speed.
As an engineer, if you can't even start a process with sobriety, rigor, and safety in mind, that cavalier attitude only amplifies as you go down the road from experimentation to design to unleashing your ideas onto the public.
It's a harbinger of what is to come if you're being a suicidal idiot during the prototyping phase. If you don't even have respect for your own safety...
Really not trying to call you out here, as a teenager I once had the idea to load up my marble cannon with dead AAs (they're free!) and got a "do you really think that's a good idea?" from an environmentally conscious adult when I went asking for dead batteries.
I love his entusiasmen for engineering and having the drive for a multi year project, even when the result is just another trebuchet. All while teaching physic in an entertaining way.
I don't get how this is close to driving through a drive through.