first time feather build

[chris knee]

hi guys, i think i have nearly everything to start work on a new feather, the only thing i think im short of is a firing mechanism for a co2 flipper,does anyone have any ideas what i might need for this please, i have got 2 gimson gr02 motors, 2 electronize speed controllers, i have a radio that came with a reciever, a vast amount of 20mm angle iron, a pair of banebot wheels, an old co2 fire extguisher, and a regulator, is there anything else i need?

[Anttazz]

Re: first time feather build

Quite a lot missing from that list, but I assume you have some of it and just haven't listed it?

From the pneumatic side of things:

Some sort of solenoid valve and a way to fire it, the ways i've used is a switch pressing a servo or a Battleswitch.
Ram
piping, connectors, etc...
on/off valve for the CO2 tank
buffer tank (optional)

Possibly more but I can't think off the top of my head.

[chris knee]

Re: first time feather build

sorry forgot to say i got loads of tubing and elbow joints and other bits and bobs,

[Bodge Job]

Re: first time feather build

A dump valve is needed, just an on/off valve with one port open from the air would do. Needs to be accessible though

[chris knee]

Re: first time feather build

right, i seem to have all the parts now, motors, speed conrollers, ram, co2 bottle, tubing, valves, batterys, wire, a lot of angle iron, now where do i start lol

[daveimi]

Re: first time feather build

What kind of shape do you want to build, do you have any plating / armour?

[chris knee]

Re: first time feather build

i havent thought that far ahead yet lol, its going to take an age getting all the bits together in the right order, i was going to make the chassis out of 20mm by 20mm angle iron, then put in some kind of base plate to attatch all the gubins to, but i got to be careful not to get to heavy,

[daveimi]

Re: first time feather build

Before you spend an arm and a leg sit down and decide what you want to build first. As a first time builder I'm realising that robot building isn't the cheapest thing you can do, and that you'll throw money away buying parts randomly without an idea of where the robot shape/design is going.

[chris knee]

Re: first time feather build

having doodled for a bit i have now come up with a sort of idea for a bot, but i am having problems with the pnuematic side of things, i intend to have a sharp pointey thing attatched to the main stem of the ram, and have it fire out of the front of the bot, i am unsure of how to fire the thing, do i put two co2 pipes on it, one for firing out and another on the other end to retract it, or do i do what some flippers have, a bungy to retract the weapon, also could anyone point me in the right direction for the components i will need for a firing mechanism, it is a low pressure system 20oz co2 bottle, trevor reg, 10mm nylon tubing
thanks guys
chris

[shakesc]

Re: first time feather build

You could bungee it but a 5/2 valve so you can use CO2 to fire and retract would also work

A good how to here

http://howto.killerhurtz.co.uk/pneumatics.htm

Other info

http://www.airlines-pneumatics.co.uk/we ... =S07012325

http://www.teamonslaught.fsnet.co.uk/pneu.htm

[Liftoff]

Re: first time feather build

as for retracting the cylinder I think there's another way, and you could do away with bungees and Co2.
If you plug the retract side of the ram, the trapped air will act like a spring and pushes the piston back again when Co2 press is released. Having said that I have not tried this on my machine as the weight of the flipper eliminates this need ...

[maddox10]

Re: first time feather build

as for retracting the cylinder I think there's another way, and you could do away with bungees and Co2.
If you plug the retract side of the ram, the trapped air will act like a spring and pushes the piston back again when Co2 press is released. Having said that I have not tried this on my machine as the weight of the flipper eliminates this need ...

That will give loss of stroke, speed and maybe an blown out endcap.

I toyed with that idea, but added a small buffertank to the setup to avoid a very sharp pressure rise in the closed side.

Wasn't satisfactionary. Bungee will do nicely.

And the weight of the arm doesn't do anything when the machine lays on the side.

[Liftoff]

Re: first time feather build

yes a small buffer would be a good idea, but I fail to see the sharp pressure rise and risk of blowing an endcap.

I suppose that if you put 10bar on the extend side and blank the retract side at atmospheric press, the result would be that the piston will extend until the pressure on the blanked side balances at 10bar, the ram is built to withstand this pressure so I can't see the endcap being blown off
Loss of stroke and speed would be an issue tho Anyway I'm no expert and not having tried this out yet, I'd go by what maddox is telling you, Chris.

And the weight of the arm doesn't do anything when the machine lays on the side.

Ah, our machine is built in a way it won't stand on its side, it's either on its feet or on its back :wink:

[Gabe01]

Re: first time feather build

Have a careful think about a pneumatic spike, the chances of it being effective are very low. If you don't have a grip on your prey, you may just push yourself away

[chris knee]

Re: first time feather build

i have thought of that, so was going to angle the ram downwards at an angle