SpudFiles

Hey where did all your snow go?!

Where do you think all yours came from? L0L! :reindeer:

jrrdw wrote:Where do you think all yours came from? L0L! :reindeer:

LOLOLOLOLOL!

Well, winter was darn lame...

But, my cannon evolved! My welder had the idea of driving the piston with a pneumatic cylinder actuated with 3/2 valve, and as its chamber sealing it opens plenty fast

Managed to shot an almost full 0.5L beer can around 80 meters with the prototype setup, also have a golfball barrel witch still needs the 1" thread

almost full

Had a fun day of shooting with my welder

[youtube][/youtube]

I kinda hate to do this to you guys since it'll be awhile till I can get some actual shooting done, but I'm just gonna leave this here.

Whyyyyyyyyyyyyyy would you do this?!

jakethebeast wrote:Had a fun day of shooting with my welder

hahaha looks like a lot of fun

I kinda hate to do this to you guys since it'll be awhile till I can get some actual shooting done, but I'm just gonna leave this here.

Details man, details! What on earth is this wonderful contraption? Is that real CF furniture?

jackssmirkingrevenge wrote: Details man, details! What on earth is this wonderful contraption? Is that real CF furniture?

Ha, didn't want to spill too much before I got to post it for real. I wanted to upgrade my old hybrid, but after everything was accounted for it ended up being a completely new gun. The pressure gauge is the only old part I kept.

The CF is real.
I can't do much shooting in the garage, tested some golfballs and an Al. slug on a 1/8" steel plate. (~2500 ft-lbs)
I cannot believe it but the golf balls survived the impact.

Love the hinged barrel! Is there some kind of seal involved or let the gasses escape where they may?

The pressure gauge is the only old part I kept.

I'm glad you did, it adds a certain je ne sais quoi

ITWOST

Bought one of these to fool around with

http://www.goldmine-elec-products.com/p ... ber=G19812

SMC Manual link
http://www.smcpneumatics.com/pdfs/ITV.pdf

Basically it's a 15PSI 0-5VDC digitally controlled regulator. They are really accurate - I've used them before in process automation - but never really considered them to be a useful spudding tool because they normally are about $200. For $20 - you can control a chambers pressure via Arduino and do it pretty accurately! This particular model is suited for .75PSI to 15PSI. It's 12VDC and uses 0-5VDC signal, which is very convenient because that means a simple arduino can directly interface with it without any special shield to translate it's signal!

Given it's low pressure limit - it's not terribly useful for a pneumatic cannon, but rather it will serve well as the fuel side pressure regulation on a hybrid cannon - up to about a 10X mixture ratio!

Awesome find
PS approves

POLAND_SPUD wrote:Awesome find
PS approves

I think my blatant mentioning of Arduino compatibility was inspired by your works haha

I approve also!

What state is it in when no signal is sent? Does it act as a closed valve and when you send a signal it opens and regulates to the set PSI?

I'm just thinking about hybrid automation. If you had one of those hydraulic ball valve with an actuator, you could vent, fuel, and add air at the touch of a few buttons. I suppose if it was all programmed on an Arduino circuit, you could even have it more automated than that.

MrCrowley wrote:I approve also!

What state is it in when no signal is sent? Does it act as a closed valve and when you send a signal it opens and regulates to the set PSI?

I'm just thinking about hybrid automation. If you had one of those hydraulic ball valve with an actuator, you could vent, fuel, and add air at the touch of a few buttons. I suppose if it was all programmed on an Arduino circuit, you could even have it more automated than that.

Just a correction first off - it's been a while since I did a manometric calculation. For propane - (assuming you have a proper expansion chamber to avoid liquid entering this regulator - that will throw off pressure values for sure!) you should be able to use this regulator for 22X-23X mix ratios! Not bad at all. You can easily get away with a much simpler solenoid valve for the HPA as it can be throttled. A little PID loop will prevent overshoot of the final pressure assuming you have a high enough pressure scan rate on your pressure sensor.

0VDC, it would have a set point of 0PSI - which is determined by the electropneumatic layout of how it works - (equally interesting). Basically the whole unit works as a valve - and if the input is 0VDC, the "air supply solenoid valve" would be closed, and this will seal the output assuming (this is the kicker...) the input is less then 30PSI. If the input is over 30PSI, I suspect that leakage may start and the supply fluid will force it's way through the valve. So basically for this to work, you're going to need a pre-regulator to knock your supply down to about 20-25psi.

The automation strategy is only limited by your imagination!