Here's a ping pong paddle hit with a 750 MPH ping pong ball :
That dimple is 1/8 inch deep.
Here's the back :
When we get into the supersonic range, there's a nice clean hole through the paddle.
The world record of Mach 2.8 puts a hole through 3/4" plywood.
The current world record for this is 976 M/s or Mach 2.8
I've designed this cannon for 100 PSi/100 C helium. Using that gas, the math says exit velocity of 4470 MPH/Mach 5.6/ 2 kilometers per second !
here's a pic of the pressure assembly :
The tank is heated, and rated to 150PSi/100C.
Happy Friday everyone !
I know some of you know what I'm up to.
I want to make a ping pong ball go so fast it melts when it hits air.
For those that don't :
In 2013 a paper was published by Purdue university about making a ping pong ball go faster than sound.
This paper : (see PDF)...
Very cool !
I was just curious.
I have a friend in the local university glass blowing dept. , so no worries. ;)
I've made several lasers from scratch, the one on my list now is a free-electron laser.
Another thing I learned from Scientific American !!
I'll dig into that.
Re: the argon laser.....Did you actually glassblow the globe fittings on that !!?
I miss that book....mine was so dogeared I started just rolling it up.
edit ; I have a few of the original sci-am articles.......the book seems to be way more rare.
Here's the popper.
The 3/8" tube assembly with the cylinder goes inside the tank via the 'tee' assembly at the back, it's coaxial.....
Tank fill is through the side port with the valve. The trigger is done with the straight through tube...Trigger is tank pressure+50Psi.
The pointy bit is a...
I've seen a sig or two here with mention of this book.
I'd love to hear stories about projects from this book......I made more than a couple of these.
Reprints available? I loved mine, it was a sad day when I lost it.
That would totally work, I considered it.
You lose the cool factor of the laser trigger though.
Ultimately, it boiled down to price.
I got it done for $52 with pneumatics.
I got my cylinder today, I'll put another pic up an an hour or so.
There is no delay !!
One slight defect in...
The world record holder, to my knowledge, was just using a thin wire and a neon sign transformer to 'arc-melt' the mylar.
Here's the cannon :
The 'popper' needs to be inside that stainless helium tank, or isolated with a window or something.
The mylar burst disk is held by the...
We are on the same page, I was thinking a modified 'swagelok' fitting with a plastic ferrule....
As much as I'd like the 'cool factor' of the laser trigger, I have gone with a simple co-axial helium line and a $50 'air actuator' with a pin.
I should have it next week, I'll get a...
I am working on a project where I need to 'pop' a mylar burst disk inside a pressure tank.
One of the methods I came up with to do this, is to use a laser.
However, to do this, I need an optical window assembly I can screw into a tank : basically, a stainless steel fitting with say a 1/4" NPT...
I am really happy to have found this site !!
After reading some 'welcome' threads, and a couple random laser threads you have already answered every question I had, (and saved me 200$ ).
I'm a little shocked I've never ran across this site before, I was searching some esoteric...