Adaptors and fittings for full pressure flipper

[evristow]

So a word of warning on expanding liquid co2 to gas into your shuttle valve ...it'll freeze!

The design is based on this spud gun valve: http://potatogunwarrior.tripod.com/valve2.htm. So the CO2 is fed to the buffer through the shuttle valve, this way I managed to come with a really compact system, as you can see in the attached PDF from my early design made in PowerPoint. For better viewing just set the PDF reader to presentation mode.

In order to prevent liquid from the tank into the valve, I thought about using an anti-syphon tube. But, thinking again, this might not suffice, still having a lot of risk to freeze the valve.

To solve this problem I decided to run a macro line or other pressure resistant hose from the main tank manifold to the buffer. And place the Auxiliary Valve directly on the Ram. With this the dump valve will be placed on the main manifold and the CO2 will flow from it to the buffer manifold. Time to change the design a bit, back to Solidworks!

On the main valve, I am thinking... Since the hole system will be pressure tested, I might use the core from a Parker MB valve and machine a body for it with 5/8-18 UNF Male on one site and G1/2 or ASA (CGA-320) Male on the other. The burst disc would be placed before the valve itself, just after the 5/8-18 UNF thread.

Also, the Pure Energy bottles have the PI Mark, just checked on the bottle I received yesterday. Sadly they sent by mistake an 20oz instead of an 16oz.

Cheers,
Eduardo

[woody]

Ah yes ...the spud gun valve concept

http://www.robowars.org/forum/viewtopic ... 7348d37ae5

The trick is to get the Bl00dy things to work for your application!

[evristow]

Yes... That is always the issue: Getting the bloody thing to work! Hehehe

The redesign is almost thought through: need to shorten the main tank manifold, connect a flexible line from it to the buffer tank manifold, place the SPRV and Dye Gauge on a T and the dump valve directly on the main manifold. The auxiliary valve can go on top of the main manifold, connected directly to the shuttle valve back chamber by two 90° Elbows or along the main tank with only one 90° adaptor.

The major issue, apart from the obvious ones, is weight. Right now with all the components for the pneumatic system, drive train, electronics and battery, I still have near 6kg to build the outer structure, armour and wedge. I might save a bit more since some of the weights are a bit overrated in my spreadsheet (eg. manual valve 300g).

I've read that Robowars Australia topic mote than 100 times, it is a pity that Trent never completed that robot. My goal is to get is ready for the UK Featherweight Championship in September, but I still need to check the cash flow and finish the design before starting the construction per se.

Thanks again for your attention and awesome material!

Cheers,
Eduardo

[woody]

Here's my solution to the std paintball valve.

A 16 oz paintball tank and a rethreaded valve from an Aqua medic , JBL or similar bottle.

http://www.reptilica.de/images/products ... e-500g.jpg

[evristow]

Woody,

That is a really good idea! I definitely will need to re-think de components layout, since it was supposed to use a straight valve. But it is doable

I've searched the last couple of hours for those valves, but only managed to find bottles with valves at a really expensive price, more than £40 Do you know any where that sells these valves without the bottle?

On this search, I came across with one valve that might be the one: Co2 & Mixed gas valves. It looks heavy, but might be available threaded to 5/8-18 UNF.

I've also found other interesting valve: http://www.rap4.com/paintball/os/rap...ff-air-adapter. It isn't suited for the application, but using a drilled trough Pin Valve as an adaptor and burst disc support might work. Just an idea...

Since from the tank to the buffer the CO2 will be liquid, the paintball on/off valve might work. I will disassemble one of the valves that I bought to see if their bore can be enlarged a little.

On the other hand, some things are decided and already arrived, such as the Wizard of NOS SPRV, threaded to G1/4 BSP, and the 5/8-18 UNF to G1/2BSP.

Cheers,
Eduardo

[woody]

John from roaming robots uses Jackson Keay as his supplier.

http://www.jk-cylinders.com/?content=supplies

might be worth asking them.

[leorcc]

@Woody,

That setup looks familiar.

[woody]

File comment: Wazio's Highroller pneumatic setup.

[leorcc]

File comment: Wazio's Highroller pneumatic setup.

That's why it looks so familiar.

[evristow]

LOL! I just harvested some pictures from the forum and saved them for future reference. That was a really neat setup!

Since the day I saw The Judge, Ziggy and Rocket (Wazio's 60) live at the Robogames, I have the desire to build a high pressure pneumatic system, last February seeing the UK heavyweights just confirmed it.

Back on the robot, I am really thinking about what woody said: I have had success expanding the liquid to gas thru the buffer. Since liquid CO2 is a lot more dense than the gaseous form, the small flow from the paintball on/off valve is not a issue any more, right? Is it worth to use a dip tube?

Cheers,
Eduardo