Can you heat a co2 ram ?

Well it worked fine for us for 3 years :proud:

you normally have around between 1 hour and more normally betwwen fights it should defost them selfs in that time with the heat in the halls

iv seen some robots have a hair dryer on between fights to heat up there ram

my dad dont bother n just says its going to be frozen after 1 flip anyway

Hairdryers were banned last year due to useing too much power from the pits as well as makeing bottle pressure to high.

I liked the idea of an expansion tank from Woody also the 6mm pipe idea from Dave,so i thought this would be good to try?
http://www.fatbobspaintball.co.uk/Air_and_Co2_Systems-C02-Co2_Fittings/c12_151_159/p650/Coiled_Remote_Kit/product_info.htmlhttp://www.fatbobspaintball.co.uk/Ai...ings/c12_151_1 59/p650/Coiled_Remote_Kit/product_info.html
I will fit it between the co2 tank and the manifold.The idea is to slow the fill rate, act as a anti syphon,and also because of the pipe lenth be a kind of buffer befor filling the main buffer.
At the shop i also bought some paintball lubricant that they use for servicing the guns,not so much oil,more watery stuff.I tried a little on the piston an it defiantly is better to manualy pull the piston up and push it down.

fat bobs is bout 3 miles away from me, i didnt know you were close

IMHO ....The piston / O Ring should be a very light / loose fit in the ram bore.

No the piston has always been very tight,two hands and a twisting action to pull up,now its a lot easier.
maybe thats my prodlem?? i hope so.Just a bit of oil.:crazy:

Sorry Kenny,
No where near.Blackpool.We went on sat..nice guy,he was saying co2 is old hat now.. all new kit runs on 5000psi hp air,not sure why.
mayde our sport will follow?

at 1st beauty was tight - my dad took the o ring off and it was alot better - that was the old ram

he has done similar to the new one to - put some oil in but i thought it wasnt flipping as good as it was at the RR event

Andrew, the reason that paintball is going to compressed air at 3500 - 5000 psi is because first, its a consistant shot pattern ( no pressure drop due to cooling gas ) second, quicker recycle or shots ( my electronic marker thats not all that quick fires an accurate 28 balls per second. Co2 cant cycle that quick without makor pressure drop problems ) and thirdly, with one charge I can nearly fight all day passing over 3000 rounds through my marker and whats more, I will still have some air left so that I can clean and test the marker at home and lastly, air is easier to refill that Co2. Its litelally plug and play. Plug it into the air source and watch the pressure gauge.

earlier air bottles were 3500 psi. We now use either 4500 or 5000 psi bottles now.

I hope this explains it for you.

One note, in the early days of Robotwars pneumatics a few people did indeed try compressed air. Paul Cooper from M2 and Technobots for one. But they switched to Co2 due to the higher amount of stored shots. A steel or Ally air bottle would be huge, weighty and very fulnerable. I have a diving bottle at home filled to 5000psi air. I use this to refill at home. This bottle is very heavy.

Regards.

Mike

For paintball CO2 is old hat, not many people are using it anymore, and most of those are the ones who have the kits from earlier days and dont want to spend more cash on an occasional outing.
I think Im the last one still buying CO2 bottles at my local supplier.

The reason most of us started to use CO2 is the 1000psi/70bar rule.
A 3L bottle contains 2 kg of CO2, what means expanded, at room temperature and pressure 1024L of gas.
Thesame bottle filled at the max pressure for robot wars contains 210L of room temp and pressure gas.

This difference is made by the liquifation of CO2 at elevated pressures. But to evaporate that gas you need energy, warmth. In a robot that energy will be taken from the surroundings, and mainly the spots where the gas is expanding/evaporating. With the advent of buffertanks on Full pressure CO2 systems, the bottleneck is most of the times the bottlevalve. But also were the valves/pipes open into the ram.

With the first FP machine I did build, Project2:Hexem I had the bright idea to use 2 bottles, to gain more flow- 2 bottlevalves have better flow than 1. But this caused the feed lines to the valve to frost over, even after the first shot. And the 3/2Woody Valve (the one now used in KaPut) started to chew up the orings inside and therefor getting stuck after a few firings.
My solution in Project2 was to make the feed lines longer and pass over the H7 50W carbulbs that made up her angry red glaring eyes. It helped, but wasnt good enough.
Second machine, Tough As Nails, with almost a simular setup I tried to solve the freezing as light as possible (TAN was from the start on the edge with the weight) And there I opted for the bend up short diptube. This did work, untill TAN gets flipped. Then the liquid CO2 gets in the valving and tubing freezing up everything.
KOS has solved this problem during the years.

Same periode, HARD, less problems due the very small ram, but still frosting of the bottle and tubing.Thanks to the ali finned collector less problems with the small regulator and valve (based on the Woody valve)

The next machine, Gravity in its first incarnation used a hydraulic 3/2 valve and proved less usefull, as the valve leaked internaly.
These machines were participants in the Dutch Series II.

The Gravity III incarnation we have seen in the 7th wars, had the advantage of the learning curve, and a lot of talking over MSN with Woody.
By adding buffertanks, multiple bottles oriented so that liquid wasnt being drawn and Burkert Valves on 36V most problems were solved. The mass of ali in the Bottles, the rather long feed lines to the steel buffertanks and the small diameter but rather long buffertanks gave a lot of surface to exchange warmth from the suroundings into the evaporating CO2.

Andrews Wedgy/Hannibalito2 profit from a few more years of experience.
The bottle feeds an ali finned collector trough a liquid stopper- in effect a flow restriction- but from there on no hole is smaller than 13mm.
Thus the evaporating gas still needs warmth, and when the bottle cools, pressure of the gas drops, lowering the power. And making possible that liquid or solid CO2 forms in the collector, buffertank and so on.

The allowed ways to avoid the cooling problems.
1) lowering the amount of gas evaporated in a certain time. IOW Reducing flow to the ram.
2) More heat exchange surface/more thermal mass.

Disadvantages.
1) Diminishes the power of the system, and that is a waste of weight, as that is better done with a smaller ram.
2) adds more weight in dead weight/space to form the heat exchanger flanges/coils/mass.

Just knit a woolen sweater for the ram. Problem solved. :)

Mario kindly supplied the ram in Ka-Putt! ... and whilst we both exchange bits /ideas it was to my way of thinking to tight.

The bore is 50mm and the O ring was made by Mario. I replaced this with a smaller section std 50mm o.d. O ring ...this actually floats in the original groove and only seals properly when pressure forces it against the cylinder wall.

Thought i would pop down to my local gas supplier to buy/rent a co2 bottle to use at home testing wedgie.
Sorry sir,cant do.. (something about back street garages using it for welding)our suppliers wont do small bottles.. ok how much is a big bottle?..about £8 a month.. so thats what im doing after ive filled out the application form in triplicate!
He said.. why not use nitrogen..i can do nitrogen in smaller bottles not as much rent.

So the question is.. can i use nitrogen as a test gas at home and will it do wedgie any harm?(weights/pressures etc)

i dont no much about what your going on about but im sure nitrogen and co2 are very different?

and if your trying to sort the freezing problem then i guess ud need to test with co2 as thats what is making you freeze

Youll need to regulate the pressure of the nitrogen down to less than 1000 psi .....once youve done that you can use nitrogen gas in Wedgie.

I dont know,just wondering whats the differerence is in a wedgie type system.But you are right,i need to stick with co2 for my problem.

Nitrogen is not liquid in the bottle, but already gas. Since a similar size bottle can contain more mass in liquid, you get more flips out of a bottle filled with liquid CO2 then you would with 1000psi Nitrogen.

But because you dont have to boil nitrogen, you dont have to draw heat from the surroundings, so no freezing.

In Wedgie a 1000psi Nitrogen filled 12 oz bottle will contain about 33L of gas.
(to fill that bottle with 1000psi nitrogen, youll need a feed bootle-200 or 300 bar nitrogen, a regulator that can achive 1000psi and the connection to a paintball bottle)

That will result in a very powerfull first stroke. But a bottle that is half empty.
Second stroke will be less powerfull and the third, let us say, a limp wrist will do more.

If my calculations are correct.
A one litre high pressure paintball tank @ 5000 psi holds much the same energy as a 0.6 kg ( one litre volume ) co2 tank... approx 33 litres @ 10 bar.
With as Mike pointed out the benefit of NO decrease in pressure due to freezing but there is a weight penalty.

Do you think we will have to change to air or nitrogen in the future,what with global warming and stuff?

No

Nitrogen is now not allowed by the FRA rules, so unless there is some legislation preventing the use of CO2 then it is unlikely to be used in the future.

The amount of CO2 we, roboteers over the world, release during a year is nothing compared to the cow farts of One Zulu tribe.

Compare to what I do with my car. 180 grams of CO2 for 100 Km. For events I do about 18 kg of CO2 to get there on year base. And thats including complete Team RCC.

Now imagine 2 500 000 cars in Belgium alone, with at least the same output, not related to Robot Wars

What enviromental impact do we have with or few 100 over the globe.

Isnt the CO2 captured from the air? (closed system therefore not actually contributing to global warming at all)

Why is heating a ram unsafe anyway?

Mark.
CO2 is a waste product of other processes. Like making hydrogen from natural gas(98% of the hydrogen we use is made that way). Thats more efficient(and therefor cheaper) than taking the small % CO by fractional distilling air.

Heating a ram unsafe. Depends how warm you make it. If you go over 40°C it becomes very uncomfortable to handle. And that could pose a problem when other people -like tech checkers or arena marchals- need to handle the robot.
But in itself, with the mandatory 1000PSI relief valve its not dangerous.

Thanks Mario. From looking at the phase diagram I would guess you wouldnt want the bottle to reach above 31°C either?

The worst that can happen for the combat robot is that the valves dont work. And the PRD will make short work about the overpressure.
Then it becomes a pure loss of gas.

Wont the local pub have the smaller co2 bottles? they can get them changed for u too cant they? its what we use for portable mig. use the argon/co2 mix in the workshop but a little CO2 bottle is handy on site. then just use refill station for paintball bottles. wont be liquid draw so turn bottle upside down when decanting. i dunno what im on about but the pub gas/Cellar Gas/Drink dispense gas whatever you wanna call them, shud work right?
black bottle. theres some with nitrogen in the bottle that pubs use too isnt there? dont get that 1 if there is. ill shut up now.

I dont think the CO2 from a pub would be a good idea. I heard of some guys trying it before, and they found out the hard way that the CO2 bottle has lots of small beads in to help the liquid change to gas and you wouldnt want them flowing through your valves etc.

What size of bottle is wished for?

I have here several sizes of bottle.
80 gram sparklet (steel)
12 oz paintball bottle
20 oz paintball bottle
1.1 kg fire extinguisher
2 kg fire extinguisher
3.5 kg bottle - revamped 5L ali oxygen bottle, recertified.
10 kg bottle with dip tube.

Recently removed - to bulky ,unwieldy and heavy. 50 Kg CO2 bottle.
Other bottle I can get without any hassle, 27 kg bottle.

mario, how much for the 27 kilo bottle, and can it be refilled in the Netherlands?

Bottles are only filled by the supplier, or the ones in the same group of firms.
So, the bottles I can supply are only refilled by the firm I get them, and that is close by, so deep in Belgium.

And the pricetag is a monthly fee for rent and about ‚1 per kg of CO2.

My bottle is being delivered tomorrow.
It€™s a 34kg c02 with dip tube (not for food use).they won€™t supply anything smaller unless you are a pub etc.
The costs are€¦ £26 to fill, £18 to deliver and £7 per month. And it has to be on direct debit€¦oh... And I have to smile and say thank you.

andrew, you should just take it 2 events and fill it up as much as you can :P

my dad fills his bottles up at the end of events (RL and RR and my dad are in dublin so they wont find out :P) i ask him why he does it and hes like just incase i do testing at home - but we dont even touch the robots at home lol

Delivery I dont suffer from, because I pick it up.

But the rest is about the same Andrew. And my supplier is a fun guy, lots of laughs. But he cant change the price. he needs to live too.

beads in the pub gas co2 bottles?. u sure? i didnt know this. did anyone else know? i just bash metal and weld i dont understand all this co2 stuff.

the beads in the bottle is to ensure a constaint and even flow, like the ball in some cans of beer

so these will come out if u decant the liquid co2 into paintball bottle? no way to filter them or anything? if not ill get the liquid draw bottle