Pneumatic

Im looking for a fitting that will screw into my dry powder fire exting, with a tee peice on it, does anyone know where you can get such an item????

ta
billy

Do you know the thread size?
I suspect its non standard and very fine.

Heres a possible size selection.
http://www.chinafireextinguisher.com/products/dry.htmhttp://www.chinafireextinguisher.com/products/dry.htm

hey, im looking for the pivot part that you can buy for the bottom of your cylinder, i think its called a clevis, i have the one for the top.

does anyone know where i can get these, i cant remember the bore size of my cylinder, i bought it from technobots about 1.5 years ago, and they said that it work ok, for a feather weight at 10bar, so im not sure of what size to buy, can any one help.....

Try Technobots ( Paul may be able to point you in the right direction )... or a supplier for the make of your cylinder.

What is the make?



(Message edited by woody on July 02, 2006)

It will probably have a code on the side of the cylinder in the form of a part number, quote that to the manufacturer and they will help you.

Or work it out urself?..I have an SMC branded ram with me at the momment, On the side it sais C92SB32-320 The end of the code tells me that its 32mm bore and 320mm stroke. Once you have the bore of the ram, ordering a clevis should be no problem.

thanks guys great help again!

Well, back on topic here!!! Im alive! :)

I have just been really busy with work and I moved into my new place, so new stuff got put on hold... Good news is that I have some free time every now and again so I am going to remake / finish high roller.

The high roller that I made the first time would have sucked, so I am going to start all over and make it better this time.

To start things off I got a new manifold. the cylinder will be in the middle like it should be. So now that I have that all done I am going to work with Bryan Rudy (The guy who made Ingor the FBS omni 12lb) on the CAD. Hopefully in the next few weeks we will have the CAD all done then the CNCn can start!

Look for the same-ish shape, but the frame will be alot different.

Same BaneBot units for drive and a big Li-p for power...

Any questions just ask! Also, here are a few pics of the new unit..

http://i79.photobucket.com/albums/j147/wazio/IMGP2398.jpghttp://i79.photobucket.com/albums/j1...o/IMGP2398.jpg

http://i79.photobucket.com/albums/j147/wazio/IMGP2397.jpghttp://i79.photobucket.com/albums/j1...o/IMGP2397.jpg

http://i79.photobucket.com/albums/j147/wazio/IMGP2396.jpghttp://i79.photobucket.com/albums/j1...o/IMGP2396.jpg

~Chad

I see you put your system all horizontal. How do you stop the setup from sucking in loads of liquid co2? Or are you using compressed air or something like that?

I will add an anti-syphon tube to help combat this problem. For the most part I will just have to live with it. One of the big differences between the FRA and RFL rules is in the use of pneu systems. I have to jump through hoops just to use the Mario cylinder. So with that being said I am going to use stock parts that have pressure certs so I dont have to worry about anything. I will just build around the large set up. Tiz not THAT bad, but I would like something that looks lot cleaner... Something like some of Marios new set ups. . .

~Chad

like mine. :)

Picture? Or is the pic Mario sent me the one that he made for you? I would love to use something like that! But again, I would have to get it pressure tested so that is a pain in the butt...

Actually, Mario! How much would you want to make me one of thems for? I want one like the first one that I made... L shape with the tanks on top of one another to save weight and space. Gauge on top so I can see it. bleed valve on the end by the cylinder. . . It would save me alot of weight and space to just get a custom part made me thinks + I can tap the holes to the correct size so I dont need to use thread adaptors which are a few oz per unit. If I can afford it ill just do it that way I guess...


~Chad

At the moment I cant make one, a broken left index finger is playing havok with my available working time
Also, the house needs a lot of attention.
And the running up to the UK championships .
I can look into it, the earliest in september.

DOH!!! Got a CAD of one that I can make myself?

Hope your finger gets better man... I hate when you hurt your hands!!!

~Chad

I made the Hannibalito collector just by messuring where everything needed to be, took the minimum wall thickness, and started drilling and milling.
I dont believe Ive a scetch around were the dimensions are noted.

Also, now the left hand is out , next month, probably, a heavy duty chirurgy will be undertaken in my right hand.

Well, I suppose I will just have to CAD my own. . . I will send you an E-mail about the thicknesss I will need to maintain... How the heck did you hurt your hand?

~Chad

Well, I will start to get my thread back now THANK YOU VERY MUCH! ;-) Anyhoo, I am getting back to work on the 30lb flipper. I am working with a friend, Bryan to CAD up the bot and do it right this time. Not all half ass like last time! But as is I will have about 7ish pounds left for the arm and armor. A picture is on the profile.... All waterjet and AL frame. The arm will be some sort of steel tube. Armor will probably end up being a sheet or two of paper :-)

hi chad,
id hate to offend, so please take this comment as just my personal opinion, not a critasism.

there are a lot of connections on the pneumatics. i wonder if moving the flipper pivot to the very back of the bot and putting the buffertank in line with the valve might save half the weight of your fitting?

this might let you have a few more sheets of paper on your armour? :) lol

as i say, no offence meant, i just see a lot of fittings, which are heavy.

LoL, no worries james... The reason I have it how it is, is because I have all of the fittings from another project. I want to, in time, replace all of the fittings with an AL manifold.

cool, im always worried about people being offended by my comments, so glad it was taken as meant.

what are the specs on that system? that looks like a big ram!

That is what the forums are for... Helping out and showing off. . . .

That is a Mario super awesome amazing sepcial custom. 70mmx80mm Hopefully I will be able to flip a bot 2 or 3 feet in the air :-) I hope to have it all done and working in a month-ish amount of time. I am looking foward to seeing how it works. I got a nice big Li-p for it which I that I am also looking foward to seeing how well it works.

2.75 inch bore 3.14 inches of stroke
Swept volume of 18.6 cubic inches
Pressure = 750 psi

Work that can be done by cylinder = 13,950lb-in

Divide by weight of bot to be moved 13,950/30 gives 465 inches or 38.75 feet.

A 50% fudge factor in practice seems to take into account losses etc in a flipper.........So 19 feet.

19 holy moly thats great. I would be happy with even half of that! A question has been asked about how strong the arm support and cylinder mount will be... I think it should be fine.. I will have 2-3/4 AL supports that the arm and cylinder will mount to. Here is a pic: http://www.teamwazio.com/c-mount.jpgwww.teamwazio.com/c-mount.jpg

The arm / pivot looks good... not sure if your wheel mounts will take the strain of 4000lbs+ of thrust being applied to a 30lb weight.

It may be desirable to have the chassis flex enough to allow the base to touch the floor .....thus allowing the floor to take a good percentage of the load away from the wheels and mounts.....or perhaps squidgee tyres?

There is also going to be a fair ammount of bending moment applied to the chassis forward of the ram .......it might be a good idea to add a brace of some sort?
You could incorporate your Ali manifold and bottles as structural strength.

Just thoughts ......:)

Put a new pic on the profile...

~Chad

Wow, looks beefy. Any ideas yet on what youd use on the near vertical front tubes to get under your opponent?

(It is worth making sure that the weight isnt lifted too far forward - but that gives me an idea that if you have some wheely bars extend from the base plate out the front with rollers that only engage with the floor when the flipper is taking a load that might help spread the load of a somewhat painful theoretical 4000+lbs!)

You pulled High Roller out of Robolympic 2007? :sad:
We were looking forward to seeing it fight Devastator, which is Marauder with a new name and owner (my brother).

I might change the frame design a little and get rid of the base plate. I am messing with the CAD now... The arm is not done yet, it will have forks on the end of it...

High Roller will be at Robolympics (if it is done) I had to take it off the event in order to change something with the robots profile. No worries! :-)

~Chad

I put a new pic up... And changed it up a little! Just gotta add the armor now.

~Chad

Can someone draw me a picture to explain the differance between an open and closed pneumatic system with respect to combat robots? This was someones point in an argument we have been having about rules. I was told Marauder is a closed system pneumatic robot and therefore must follow the rules and the other robot was an open system robot and therefore the rules didnt appy to it.
I thought the differance was in an open you had 2/2 or 3/2 valves and a closed system used 5/3 valves. Am I wrong? Id prefer to be told Im wrong by people who know what they are talking about, because itll make a change to what I have to put up with the last week.

In an open circuit atmospheric air is pressurized, used in the pneumatic circuit and then exhausted back out into the atmosphere. This is one way that pneumatic circuits differ from hydraulic circuits. Hydraulic circuits are closed circuits. The same fluid is continually re-circulated within the circuit

Ive never heard of a closed pneumatic system .

Ok, here are some proposed rule changes to make the offending robot leagel.
These rules apply to all open system robots. Closed system robots use the standard FRA or RFL rules.

Just to kick things of
-- Standard UN modified Soda stream bottles and valves and flow restrictors containing no more than the maximum rated weight of gas.

--The ram must have exhaust ports of XX area so at the normal working extension as assembled in the bot the ports are below the piston and can therefore vent the gas.

--The ram must be locked in the extended position whenever the gas bottle is fitted. It makes no difference if the bottle is full or empty. Apart from when it is in the arena. Or EO designated test area.

--A suitable low pressure blow off device, e.g. vac hose or spring-loaded valve installed at inlet of ram.

--Damage to CO2 bottle as for closed system rules.

--Mounting of CO2 bottle as for closed system rules.

---Electric operated CO2 valve must be spring loaded in off position .


I guess we get to remove the gauges and manual valves from our robot.

Found another proposed rule.

--- I think for safety reasons with this class of pneumatics it would be worth specifying that the bottles must not be self filled (legally I think this is true anyway), but must be in the factory filled state.
This ensures that the burst discs and valve are new and safe, and that the bottle is not being filled while potentially damaged.

what is your definition of a closed system?

Daniel,
What is the supposed problem with Marauder?
Why do we need rule changes to make it legal?

Woody

Here is a link to the thread on our forum where these rules are being discused on page 10;
http://robowars.org/forum/viewtopic.php?t=894http://robowars.org/forum/viewtopic.php?t=894

If you can be bothered reading through it you will see that the problem with Marauder is that it is apparently over-weight and that a Sydney based robot called Stealth that won a large compition in Melbourne at the start of the year wasnt built within the rules. Its CO2 supply, regulator(if it had one) and valve came from an old soda stream system, the tubing is vacume tubing from a car as is a seperate solenoid operated purge valve. I dont know where the ram came from but the builder has drilled holes into the cylinder close to its maximum extension to exauhst the gas in the ram at full extension. He believes this makes it safe to use parts not rated for the expected pressures because the system will never reach its maximum before venting.
This is what is being refered to as an open system while since Marauder will not vent the gas in the ram imediatly on reaching full extension it is being called a closed system. At least that is how I am interpreting it.

My ram has a small hole in the bottom of the cilinder to vent gas, thats a definition of open system then?

Quote from Robowars Forum.

He was at least weighed in at legal weight with a full tank of gas and as his method of blipping the gas in a very small pulse at the bottle valve the decision which agrees with your calculations based on the number of flips he gets that he was only operating at 100 psi which is the line in the sand where the complex tec rules do not apply

In my opinion a 100 psi relief valve should be fitted in the ram supply line.

--The ram must be locked in the extended position whenever the gas bottle is fitted. It makes no difference if the bottle is full or empty. Apart from when it is in the arena. Or EO designated test area.

Ummmm I can understand this one, but I think it is more easy to have something to lock it down. And if it is Marauder that is the problem, I really dont understand this.


--A suitable low pressure blow off device, e.g. vac hose or spring-loaded valve installed at inlet of ram.

I think this is waste of weight! If you have a ram like most if not all Mario FP rams it has a hole in the bottom. If it were to fire and you had the arm locked down it would bleed out itself along with any extra pressure in the ram. Durrrrr

--Damage to CO2 bottle as for closed system rules.

no brainer... damager CO2 bottle = bad!

--- I think for safety reasons with this class of pneumatics it would be worth specifying that the bottles must not be self filled (legally I think this is true anyway), but must be in the factory filled state.

In theroy this would be good. But when I buy a new tank at the store that is full its rahter expensive! Also, this would mean that you need to bring a ton of tanks to an event. Shoot this idea down!

I dont totally understand the problem here... Marauder has a hole in the bottom of the ram. The second it gets air into the ram it starts to loose it. I would call that an open system, right? I will have to start bugn glen.. :-p


Time for bed.. up to late. ALSO... I put up a new pic of the bot on my profile

The pressure in the system is often not a factor in the failure of pneumatic actuators in robot use. The failure is caused by the speed the piston is moving at when it hits the end stop.

As such, whether the actuator is open to vent gas or not, is not a real factor in the potential failure of the system.

Although the vacuum tubing is potentially a good idea, the burst pressures of such tubing is unpredictable and likely much higher than thought. Standard 6mm nylon tubing is usually good to at least 1500psi and when used with compression fitting will go much higher.

Sodastream type cylinders must not be refilled by the end user. As this is normally stamped on the cylinder or label, you cannot legally refill a sodastream cylinder.

You should only be refilling bottles that are designed to be refilled by the end user.

(Message edited by kane on September 20, 2006)

Leo ......your system falls somewhere in between the 2 .... yours being a restricted to atmosphere open system .....thus not truly open but not on the other hand closed.:crazy: