Pneumatic

You can see where the ram is better in this pic

http://www.bugs.nl/media/album/view.php?&path=L3J3L3J3Ny91ay1hZGFtLWNsYXJrLzEwMV8 wMTEzLkpQRw==http://www.bugs.nl/media/album/view....LWNsYXJrLzEwMV 8wMTEzLkpQRw==

Its well worth running your designs through Noels flipper calculator, otherwise you might end up with a nice looking setup that could work so much better.
the excel spreadsheet is downloadable here:http://www.hassockshog.co.uk/flipper_calculator.htmhttp://www.hassockshog.co.uk/flipper_calculator.htm

I have used it to optimise the output of a couple of flippers, feather and heavy and its reasonably accurate

Chad, the Burkert valve isnt the problem, its the let trough of the bottle exit.This is easely solved with the buffertank.

Ewan, Chads ram is a 70bore*80stroke ram. For a feather HUGE. He can afford to have a long flipperarm.

lol, yup, very big :)

Hey Chad, did you ever get closer to finishing the hammer-feather? Whereabouts can I see the most recent pics of it?

Skewer

Chad ...I agree with Mario.
The Burkert should be able to flow 46 litres or 12 gallons per sec @ 750 psi with a pressure drop of 5 psi according to the PACulator.

http://www.proautocon.com/PACulator.exehttp://www.proautocon.com/PACulator.exe
Cv of valve 2
Inlet pressure 750 psi
Specific Gravity of CO2= 1.52 ( Thats Density in the programme.)


Note :- Your ram has a capacity of 1/3 litre ....do the math to get a fill time.

You seem to be making the classic mistake of putting a big valve on a small supply.
The internal passageways of your paintball valve are less than 1/16 and if memory serves me right closer to 1/32 and restricted by direction changes.

If you replaced your bath taps with fire hydrants would you be able to fill your bath in seconds?
NO ... it would take much the same time as before.

So use a buffer tank ( a buffer tank contains a readily available and unrestricted head of gas )
I.E. A suitably rated pressure vessel with an outlet bore the same size as your valves inlet bore and enough capacity to suit ... A capacity / volume of 2 or 3 times your rams volume as a rough guide

Woody



(Message edited by woody on January 15, 2006)

wait a second....
70mm x 80mm?
full pressure?

Yes and Yes.... :)

James, yours is bigger. :)

Ok, today I made a manafold so that everything can plug into 1 block. My girlfriend is here so I have not had a chance to test it yet, but it has the 9oz buffer tank + all the area inside the manaflod. Hopefully this will help out. New picture is on the profile.

Now to put in a Pressure relief device (overpressure valve) and a blow off valve and you have a nifty little Flipper.
Imagine, this has the power of early 80kg/175lbs heavyweight flippers.

I have the blow off (bleed) valve. It will go under the pressure gauge... But what do you mean by over pressure valve? The tanks have burst disks, and they will blow when the pressure gets to be to high. Or do you mean something other than that?

I think Mario means a pressure relief valve and a vent valve to dump the gas after a fight.

The Americans dont require pressure relief valves under the RFL rules.

How much does the manifold weigh?

The whole system as is, with a full tank is just over 11 pounds.

Chad ........What is the bore / outlet hole size of your buffer tank and the size of the cross drilled hole in the manifold?

All the holes are .5 on the manafold. The hole in the buffer tank is like 1/8 Speaking of, I just fired the system with the buffer tank.. MUCH MUCH better. I was shooting a wheel 25 in the air! I am suprised how much that buffer helps! Putting a new pic up on my profile.

Remove the pinvalve on the buffertank, and mount it directly on the manifold. Its still a serious restriction like it is now.

Otherwise, take a 1/4 drill-preferably bigger- and drill out the pinvalve of the buffer.

You should be able to safely drill out the centre of the buffer tanks valve to 3/8 dia....... thus improving the flow GREATLY.

Edit ......Mario mentioned your valve...I have just realised that the fitting between the buffer and the manifold could well be another restriction... Maximise both the buffer and fittings thru holes.

What are you using as an exhaust on the ram........a small bleed hole ?

Have you added a cranked dip tube to your main supply tank?



(Message edited by woody on January 16, 2006)

I shall drill out the buffer to 3/8.

exhaust is a little hole in the bottom.

And no, no anti stphin(sp?) tube yet.

I got the system done last night... Layout wise. Ball valve before the cylinder (to make safty person happy). bleed valve at the ass end of the manifold...

http://www.teamwazio.com/TestFire.wmvwww.teamwazio.com/TestFire.wmv (this is the vid that I am showing all the US builders. I am going to keep the Full Pressure a secret till the event.)

http://www.teamwazio.com/EdTestVid.wmvwww.teamwazio.com/EdTestVid.wmv (just for the safty person at the event, because I need to get it pre approved. Has a good look at my system, So dont show and US people this vid!!!)

http://www.teamwazio.com/30lb1.jpgwww.teamwazio.com/30lb1.jpg
http://www.teamwazio.com/30lb2.jpgwww.teamwazio.com/30lb2.jpg

Just a few stills of the thing... Let me know what yall think.

The manifold has a wall thickness of at least 3/8 if I need to loose some weight how thin can I make the walls on this thing and it still be safe?

Very nice :) Im interested as to how the bodyll look, any clues just yet? :)

Looks good!

But a little tip, dont put your hand in front of pressurised gas... e.g. dont put it in front of the exhaust valve. Any small particles in the gas will be injected into your skin.

I cant for the life of me see a reason for the ball valve in between the Burkert valve and the ram......very odd!

Reducing the manifold thickness to perhaps a min of a 1/4 between any internal drilled holes and the outside may well be fine.

Persuading the safety man that the ball valve isnt reallly needed would help.......:)

Chad .......I assume that your working towards this ...
7.6. All pneumatic components within the robot must be rated or certified for AT LEAST the maximum pressure in that part of the system. You may be required to show rating or certification documentation on ANY component in your system.

Id like to point out that the burst disc pressure rating on paintball bottles is fairly high ........1,800 psi plus as a norm.
So .....the ratings of your valves and fittings should be at least that of your burst / rupture disc.
The addition of a 1000 psi pressure relief valve makes things simpler.

BTW... Whats the rating of your vent / dump valve?

Ewan, The body is going to look something like Phillips bot. The outside armor / shell will be shaped kind of like a pyramid. Front will have something around .300 Ti with the rest about .125. The base plate is 17wide x 12Long. So it will be really wide. I like this because 1- It will be easy to drive with 4 wheels and 2- It will give my arm alot or area to catch the other bot. Also, my drive will be http://banebots.com/osc/product_info.php?cPath=36_63&products_id=224http://banebots.com/osc/product_info...roducts_id=224 two of them @ 11.1v then belts to the front wheels.

Woody - ya I know, I dont like that ball valve! But that guy said he wants me to have it. Why, I am not sure... But maybe because that this is the first FP flipper in the US (as far as I know) it is just something that they dont understand yet.

That bump vlave is like 1500 or something, I dont know. I just had it in my shop, worked out well. I dont HAVE to get the parts certified, that is why I made them overkill, to get around that rule. But if I need to save weight I will make it weigh less by milling off a few 16s from each side.

The dump looks similar to the one we use in Merlin, weve used it for about 2 1/2 years in hundreds of fights on FP and never had a problem. I did see after about 6 months that it was only rated to about 300psi, but has never failed me even after a fight when its been solid ice! saying that tho it could be a different model.

The only posistive thing i could see about the valve between burkert and ram is that it would stop a miss fire if you were to open the bottle too quickly. Although personally i would have put it just after bottle as the bottle valve looks abit small and fiddly.

@ Alan
The flow from the paintball bottle is via a needle valve ......hard to open it anyway other than SLOW and once open its flow can only be considered .......meeker.

@ Chad
Id try very hard to get the ruling on the ball valve changed.

Tsk ....spelling!
Meagre ....not meeker!

Got some work on the base plate done today. 18 build days left! Pic on profile.

18 days? Plenty enough time ;)

Looks very neat so far, will be good to see how it comes together.

Got alot of work done today.... Tank mounts, pillow blocks, belt grove milled, Arm monts, all made and most are on the bot. Just need to mill some more, and get my hubs. . . Its looking good. Pic on profile. . . Or e-mail me if u want more.

Also, here is a yahoo album that has most of the pictures that I have taken.

http://pg.photos.yahoo.com/ph/wazio88/album?.dir=7a41&.src=ph&store=&prodid=&.done=http% 3a//pg.photos.yahoo.com/ph/wazio88/my_photoshttp://pg.photos.yahoo.com/ph/wazio8...e=&prodid=&.do ne=http%3a//pg.photos.yahoo.com/ph/wazio88/my_photos

simply awesome :)

strange cilinder placement, but still awesome

whats happened with ram?? the piston nylon block broke??

(Message edited by teamkenny on January 29, 2006)

Not nylon. My supplier did deliver me another material, stronger, stiffer called Ertalon 06. But it can break, and the UHMPE I use normaly cant.

the piston breaking was not a big deal. A new one will be made today outof UHMW.

That is very neat, Chad. I will have to pinch some of your design ideas for my next rebuild.

so disgustingly well engineered... it makes me feel quite ill... no gaffer tape, no bodged fittings.. I bet you even put your tools away after you..whats the world coming too?
Very impressed