I have just been asked by a customer on http://makexyz.com to give a quote for printing an 18 mm hemisphere. When I replied that this was very small and asked for confirmation that the dimensions were correct the customer replied that this was to make a paintball shell.
Now, I have no experience of paintballing but this sounds to me like an extremely dangerous idea. My research so far seems to indicate that paintball guns are designed to fire 18 mm gelatin capsules filled with paint. Putting a 3D printed plastic ball into such a gun sounds as though it has the potential to cause harm in many different ways.
I will be refusing this request but thought I would seek opinions from others in this community to see what the consensus was.
Would you knowingly print plastic ammunition for a gun of any sort?
Unless you were doing 100% infill (and even that would be debatable), the 3D printed round is going to be much lighter than a real paintball.
Actual paintballs can be dangerous, but to get hit with one of these would be like somebody shooting a wiffle ball at you.
Paintball is supposed to be fun and non-lethal. I’d suppose shells printed from any material and then filled with whatever weighed material would be considerably more rigid and harmful, maybe even potentially lethal, than a capsule that immediately deforms and tears on contact.
I could see experimenting with it yourself* but never doing it for someone else. If they did do something nefarious with them you can bet the police and the lawyers would be after you in a heartbeat.
*In a safe, closed environment with proper safety precautions and PPE.
There could well be legitimate applications for this. My first thought being as some sort of delivery system for dry or liquid chemicals in harsh environments. Or masses of tiny sensors.
@Tom_Nardi i’m just going to leave this here: http://en.wikipedia.org/wiki/MythBusters_(2014_season)#Killer_Ping_Pong_Ball
Low-weight projectiles can be extremely dangerous since they move much faster after receiving the same amount of kinetic energy as a heavier (but then slower) projectile.
That isn’t even close to being relevant.
They were accelerating the balls to supersonic velocity to get them to do damage, and even then, there was no attempt at comparing impact energy with a heavier projectile.
@Tom_Nardi still gives you a reference to what kind of damage low-weight projectiles can do. They were starting out with compressed air - the same thing paintball markers do.
But even if you printed the projectile with a super-low wall thickness, it would still end up heavier than ping pong balls while reaching almost the same velocity.
Any active #Paintball players around here?
There’s really no point in even debating this, solid paintballs and hard plastic paintball shells are already available and in use:
I concede that if you accelerated one of these to ~5x the speed the gun is capable of firing them at, they would be potentially lethal, but I don’t understand the significance of that.
Flecks of paint have the energy of a small bomb when moving at orbital velocities, but I don’t think that is any more or less relevant than a supersonic ping pong ball.
You can buy solid plastic paintballs. They are kept for non lethal self defense and would sting but while I wouldn’t like to be shot with one I doubt it would do much harm. I keep a paintball marker with them. I wouldn’t print the round balls but have thought of darts but again not overy eager to damage the inside of my marker barrel. While they sold as non lethal self defense rounds they are actually practice rounds used by paintballers to save money on paintballs. What you can do with solid rounds is turn up the velocity more as there is no risk of a barrel break (the paintball equivalent of blocked nozzle on a 3D printer) I cant see much use for printing solid rounds if you can buy them for less than 3D filament per kg. What would interest me is printing moulds that can be filled with silicone that can be filled with capsicum or propper dye or paint for permanent marking.
It’s not the shell that’s the problem it’s what might be put in it.
Don’t worry guy. Stupid people have an amazing survivability - I knew one hill billy, he shot himself in the foot and waited to go to doctor for two hours to let two friends of his finnish hunting.
@Tom_Nardi 's right - you can already buy these, and a number of companies use paintball markers to deliver “non traditional” rounds for legitimate purposes. There is absolutely nothing making them legal or illegal in the US - they are completely unregulated. If you ever want to see just how unregulated, go watch an hour of Dog The Bounty Hunter - fair warning it’s an hour you’ll never get back.
@Christopher_Gaul I’m a bit confused how printing or otherwise manufacturing what is effectively an 18mm hollow ball bearing would attract any liability here?
I have experimented with this as well, using thin wall/vase prints to create a hollow shell. Most of the balls did not even survive firing from the weapon, (PLA, didn’t test ABS) and they exploded in the barrel.
When they did leave the barrel and strike the target, they impacted with no more force than a normal paintball.
When printed solid, they impacted much harder, but solid balls was never the end desire as it’s A) cheating and B) extremely painful.
However in no testing did we end up with something I would call lethal, just a big mean pellet or bb gun.
there are tons of easier ways to make harmful projectiles for paintball guns without 3d printing. I would ask what they want to do with it because if they really wanted to cause harm they could easily freeze paintballs or buy marbles.
It’s not whether it’s legal or not, it’s whether you wish to be named in a lawsuit as a member of this Litigious Society as a result of its misuse.
I think you’d need a legally binding letter from the user that they are responsible for how they use whatever you print for them. That should probably be obvious, but you might also want some kind of boilerplate terms and conditions for everything you print for someone else.
I will print anything that is legal for anyone of age. If I print scissors for someone and they run with them it’s not my problem. Last time I checked I have not been receiving my paycheck for being 3D Printing Safety Officer.
Right Dale, let’s post a disclaimer on our sight that states you must be an attorney and write a “binding letter” to get a job done.
That’s as ridiculous as Home Depot making you write a binding letter to buy a screw driver because you might stick yourself in the eye with it.
Thanks everyone for taking the time to vote and comment. Personally, I thought it was worth debating, although I am conscious that attitudes may vary depending local gun laws and ownership. Interesting to hear that actual likelihood of injury from a fired missile is likely to be low. The thought of something other than paint being put into the shell had not occurred to me but only serves to strengthen my feelings of not wanting to participate in this project.
Great response. My phone’s been buzzing all day!
I have also attempted printing and firing standard Nerf darts. With pla or abs only, you don’t get a good seal and a lot of the pressure is lost. The foam the darts are normally made of is how they stay light and seal properly against the valve thingy. (Technical term, clearly.)
You can get interesting results by finning or rifling the darts outer surface, but still nowhere near the range of regular darts.
Trying to tip the darts with a printed cone or spiral works and they hit harder, but its really just being mean and makes a safe toy into a dangerous one, so I didn’t post the plans anywhere public.