Josh Bass
December 2nd, 2010, 01:48 AM
Hi. I will be DPing, starting in January, it looks like, a short film involving some gunplay. We have several characters getting shot, and would like to have bullet hits/blood. My friend, the director, had planned to try out squibs but has abandoned that idea.
He has built a "goo gun", basically same idea as a paintball gun, potato gun, tshirt cannon. It is an air tank hooked up to a valve with a trigger release, which is then hooked up to a barrel made of a PVC pipe. You cram your ammo/goo/blood into the barrel, manually pump (we use a simple bike pump) the air tank up (I can only get it to 30 psi before it starts to become impossible to pump further), and use the trigger to fire.
The idea is that if the goo/blood hits the person fast enough, it appears to just "appear" there, like a bullet hit, instead of being shot onto them.
We have tested it with mostly lackluster results.
We need to have several pistol hits, and maybe a shotgun hit. So far, even with the tip of the barrel at four feet away from the subject (far enough to be outside of frame on an MCU of a character), we're still getting too much spread/spatter, instead of a concentrated area of impact.
Let me tell you what we/I have tried so far.
We started just simply pouring our "blood" into the barrel. . .corn syrup and food coloring with chunks of banana mixed in.
I have tried a new mixture he come up with that was based on mashed up avocados. a neighbor who knows guns/ballistics to some degree advised putting something behind the goo (i.e. first thing into the barrel, before the goo), like a cotton ball, facial pad, pineapple core, etc., to ensure that the air hits a solid surface at the same time. So far these devices have stuck to the goo all the way to impact, resulting in a splat with a cotton ball in the middle.
I tried my own idea which was wet and torn up toilet paper, which gave a more concentrated mass, and the cotton balls, etc., did not stick, but still flew too far.
Anyway. . .using this device, any ideas to make it better? I should mention that I haven't had anything long enough to tamp the mass of goo and cotton all the way down compactly, as the tamping devices I was given fall 3 or 4 inches short of the length of the barrel.
I've attached a hastily taken photo of this gun.
on the left is the long barrel. . .about 38". The green part is the valve, see the trigger (red) on the bottom, and the air tank with pressure gauge at the back.
He has built a "goo gun", basically same idea as a paintball gun, potato gun, tshirt cannon. It is an air tank hooked up to a valve with a trigger release, which is then hooked up to a barrel made of a PVC pipe. You cram your ammo/goo/blood into the barrel, manually pump (we use a simple bike pump) the air tank up (I can only get it to 30 psi before it starts to become impossible to pump further), and use the trigger to fire.
The idea is that if the goo/blood hits the person fast enough, it appears to just "appear" there, like a bullet hit, instead of being shot onto them.
We have tested it with mostly lackluster results.
We need to have several pistol hits, and maybe a shotgun hit. So far, even with the tip of the barrel at four feet away from the subject (far enough to be outside of frame on an MCU of a character), we're still getting too much spread/spatter, instead of a concentrated area of impact.
Let me tell you what we/I have tried so far.
We started just simply pouring our "blood" into the barrel. . .corn syrup and food coloring with chunks of banana mixed in.
I have tried a new mixture he come up with that was based on mashed up avocados. a neighbor who knows guns/ballistics to some degree advised putting something behind the goo (i.e. first thing into the barrel, before the goo), like a cotton ball, facial pad, pineapple core, etc., to ensure that the air hits a solid surface at the same time. So far these devices have stuck to the goo all the way to impact, resulting in a splat with a cotton ball in the middle.
I tried my own idea which was wet and torn up toilet paper, which gave a more concentrated mass, and the cotton balls, etc., did not stick, but still flew too far.
Anyway. . .using this device, any ideas to make it better? I should mention that I haven't had anything long enough to tamp the mass of goo and cotton all the way down compactly, as the tamping devices I was given fall 3 or 4 inches short of the length of the barrel.
I've attached a hastily taken photo of this gun.
on the left is the long barrel. . .about 38". The green part is the valve, see the trigger (red) on the bottom, and the air tank with pressure gauge at the back.