RCCrawler Forums

ILoveRCRockCrawlin · 11-23-2005, 10:42 PM

hey JIA check your pms once and while. people might be trying to get ahold of you

JasonInAugusta · 11-23-2005, 10:44 PM

Wasn't supposed to go into detail?

How do you plan on learning?

ILoveRCRockCrawlin · 11-23-2005, 10:46 PM

well im not too good at that "learning" thing.

ILoveRCRockCrawlin · 11-23-2005, 10:50 PM

well since you dont check your PM's, JIA, ill just ask the questions here.

am i going to need a 2 way valve?

and i forgot the other questions cause i waited too long.

JohnRobHolmes · 11-23-2005, 10:52 PM

settle down man! its been like 5 minutes!

edit: my bad, eight minutes.

ILoveRCRockCrawlin · 11-23-2005, 10:54 PM

Quote:

Originally Posted by johnrobholmes

settle down man! its been like 5 minutes!

edit: my bad, eight minutes.

in 8 minutes i could...hmmmm what could i do? : \

JasonInAugusta · 11-24-2005, 09:41 AM

Quote:

Originally Posted by ILoveRCRockCrawlin

well since you dont check your PM's, JIA, ill just ask the questions here.

am i going to need a 2 way valve?

and i forgot the other questions cause i waited too long.

See, that's where you're wrong.

I checked my PM, but it was late, I was headed to bed, and I didn't want to get on AIM.

As far as your valve question...

Retracts move up and down and they're triggered by a servo which is connected to a toggle switch on the radio.

Move that servo to a proportional channel and it should work just fine.

After doing some research, I think the Robart 167VR (variable rate) valve is best suited to your needs.

Read it for yourself here.

With that valve and a good supply of air I think it'll work.

Here's the dimensions of the smallest Robart cylinder available. Click

With a set of those cylinders and that variable valve I think it'll be a cool little setup.

The max rating of the tanks is 150psi. The variable valve allows that 150psi to be sent to the cylinders...it controls the evacuating air, not the supply side. So your cylinders will see higher pressures than with a standard Robart valve which control the supply side air.

Should be cool...but not as cool as hydraulics.

JasonInAugusta · 12-01-2005, 05:48 PM

Hey guys...renamed this and moved it to General.

For some reason I can't get this idea out of my head.

After doing research I know it'll work. The only con to the system is that you have that 8.5" long, 2.6" diameter tank to deal with.

The 157VRX kit that cawkcrawling (

) posted has the correct variable valve to make this a working steering setup.

For 4WS you'd need a 2nd 167VR variable valve and a couple of extra cylinders.

Damn...I just might have to do this.

Anyway, I thought I'd move this to General to see what kind of discussion it brings up.

microgoat · 12-01-2005, 06:15 PM

How long would a tank of air last? Long enough to complete a technical section of a comp? It would suck to run out of air halfway up. I'm assuming the system vents the "used" air pressure and has to be recharged periodically, yes?

Last but not least, what's to keep that 150 psi from blowing the knuckles off the axle?

Remember, this is ILRCRC we're talkin' about :-P

JasonInAugusta · 12-01-2005, 06:20 PM

Ok, I've been doing the math on the Robart 3/8" bore cylinders with 1" stroke.

3/8" in decimal is .375" them multiplied by 3.14 (pi) gives an area of 1.1775".

Multiply that by the stroke of the cylinder and you get 1.1775 in³ per cylinder.

That's 4.71 in³ of air to cycle the entire steering system from lock to lock.

Here comes the problem...

The largest tank that Robart sells holds 43 in³ of air.

That's 9 cycles...and the PSI will drop as you deplete the air supply. :neutral:

If you only ran two cylinders you'd get 18 cycles...in theory.

JasonInAugusta · 12-01-2005, 06:23 PM

Quote:

Originally Posted by microgoat

Last but not least, what's to keep that 150 psi from blowing the knuckles off the axle?

Remember, this is ILRCRC we're talkin' about :-P

When I set up my hydraulics I kept the stock steering stops on the knuckles and set the cylinders up so that the knuckles reached full stop the exact same time the cylinders reached their limits of travel.

The 1" stroke of the 3/8" cylinders is just about right on with my 25mm stroke hydro cylinders.

Grizzly4x4 · 12-01-2005, 06:25 PM

Quote:

Originally Posted by chafey

air compresses, hydraulics dont. servo travel would depend on how hard you throw it and if it's still in the truck. huh grizz.

That's right! Average servo travel for me is about 10 feet when people are watching.

microgoat · 12-01-2005, 06:49 PM

Looks like we're running with an onboard airbrush compressor, then.

How's that gonna affect the CG?

JasonInAugusta · 12-01-2005, 07:10 PM

goat, you're a funny guy.

syco133 · 12-01-2005, 07:35 PM

Hope to not hijack here but can these cylinders be used as air shocks or like nitrogen shocks on a real buggy for adjusability so you could lower or raise the suspension at will I know it can be done I was just wondering if these cylinders will work.

JasonInAugusta · 12-01-2005, 07:37 PM

They won't allow compression or droop once set to a given length.

You'd need to mount one vertically in the center of the axle and let the axle rotate around them.

That way you could control chassis ride height and still have articulation.

Kinda like a stick, only a hair more complicated.

Cole82 · 12-01-2005, 08:04 PM

What if you used a Co2 tank instead of air?

RD400 · 12-01-2005, 08:16 PM

I am totally into the "try something new" thing, but, this system is huge. The tank is 1 1/2 times the size of a beer can. Then when you find a place for all the plumbing and contols this thing is going to be as big as my kids wagon. If you run an on board compressor, even more weight.

If JIAs calculations are right (I'm sure they are) you are going to use up all your air by the time you make it over the first rock.

If you make it work, great. As for me I will stick with a servo, light, strong, easily replaced.

microgoat · 12-01-2005, 08:32 PM

Why didn't i think of this earlier? Not only does it eliminate the bulky air tank, but it's smaller, lighter, and easy to carry a plentiful supply of air on board. A much better solution than the onboard compressor, and overall much cooler, too.

Use .22 blanks, the kind used in nail guns. Load 'em up on a belt-fed system. The only downside is you'd have to pick 'em all up after every run.

JakeTheAlligatorMan · 12-01-2005, 08:51 PM

Quote:

Originally Posted by microgoat

Why didn't i think of this earlier? Not only does it eliminate the bulky air tank, but it's smaller, lighter, and easy to carry a plentiful supply of air on board. A much better solution than the onboard compressor, and overall much cooler, too.

Use .22 blanks, the kind used in nail guns. Load 'em up on a belt-fed system. The only downside is you'd have to pick 'em all up after every run.

How about Baking Powder and Water? or maybe those little tablets for the Little bathtub submarines we had when we were kids?

12-01-2005, 06:20 PM	#30
JasonInAugusta 06 Super National Champ Join Date: Jun 2004 Location: Stark Industries Bar and Grill Posts: 11,361	Ok, I've been doing the math on the Robart 3/8" bore cylinders with 1" stroke. 3/8" in decimal is .375" them multiplied by 3.14 (pi) gives an area of 1.1775". Multiply that by the stroke of the cylinder and you get 1.1775 in³ per cylinder. That's 4.71 in³ of air to cycle the entire steering system from lock to lock. Here comes the problem... The largest tank that Robart sells holds 43 in³ of air. That's 9 cycles...and the PSI will drop as you deplete the air supply. :neutral: If you only ran two cylinders you'd get 18 cycles...in theory. Last edited by JasonInAugusta; 12-01-2005 at 06:25 PM.

12-01-2005, 08:32 PM	#39
microgoat I wanna be Dave Join Date: Feb 2005 Location: Cleveland, OH Posts: 8,009	problem solved Why didn't i think of this earlier? Not only does it eliminate the bulky air tank, but it's smaller, lighter, and easy to carry a plentiful supply of air on board. A much better solution than the onboard compressor, and overall much cooler, too. Use .22 blanks, the kind used in nail guns. Load 'em up on a belt-fed system. The only downside is you'd have to pick 'em all up after every run.

11-23-2005, 10:42 PM	#21
ILoveRCRockCrawlin RCC Addict Join Date: Dec 2004 Location: Central NY Posts: 1,980	hey JIA check your pms once and while. people might be trying to get ahold of you

11-23-2005, 10:44 PM	#22
JasonInAugusta 06 Super National Champ Join Date: Jun 2004 Location: Stark Industries Bar and Grill Posts: 11,361	Wasn't supposed to go into detail? How do you plan on learning?

11-23-2005, 10:46 PM	#23
ILoveRCRockCrawlin RCC Addict Join Date: Dec 2004 Location: Central NY Posts: 1,980	well im not too good at that "learning" thing.

11-23-2005, 10:50 PM	#24
ILoveRCRockCrawlin RCC Addict Join Date: Dec 2004 Location: Central NY Posts: 1,980	well since you dont check your PM's, JIA, ill just ask the questions here. am i going to need a 2 way valve? and i forgot the other questions cause i waited too long.

11-23-2005, 10:52 PM	#25
JohnRobHolmes owner, Holmes Hobbies LLC Join Date: Nov 2004 Location: Volt up! Gear down! Posts: 20,290	settle down man! its been like 5 minutes! edit: my bad, eight minutes.

12-01-2005, 05:48 PM	#28
JasonInAugusta 06 Super National Champ Join Date: Jun 2004 Location: Stark Industries Bar and Grill Posts: 11,361	Hey guys...renamed this and moved it to General. For some reason I can't get this idea out of my head. After doing research I know it'll work. The only con to the system is that you have that 8.5" long, 2.6" diameter tank to deal with. The 157VRX kit that cawkcrawling ( ) posted has the correct variable valve to make this a working steering setup. For 4WS you'd need a 2nd 167VR variable valve and a couple of extra cylinders. Damn...I just might have to do this. Anyway, I thought I'd move this to General to see what kind of discussion it brings up.

12-01-2005, 06:15 PM	#29
microgoat I wanna be Dave Join Date: Feb 2005 Location: Cleveland, OH Posts: 8,009	How long would a tank of air last? Long enough to complete a technical section of a comp? It would suck to run out of air halfway up. I'm assuming the system vents the "used" air pressure and has to be recharged periodically, yes? Last but not least, what's to keep that 150 psi from blowing the knuckles off the axle? Remember, this is ILRCRC we're talkin' about :-P

12-01-2005, 06:49 PM	#33
microgoat I wanna be Dave Join Date: Feb 2005 Location: Cleveland, OH Posts: 8,009	Looks like we're running with an onboard airbrush compressor, then. How's that gonna affect the CG?

12-01-2005, 07:10 PM	#34
JasonInAugusta 06 Super National Champ Join Date: Jun 2004 Location: Stark Industries Bar and Grill Posts: 11,361	goat, you're a funny guy.

12-01-2005, 07:35 PM	#35
syco133 RCC Addict Join Date: Jan 2005 Location: Green River Kentucky Posts: 1,067	Hope to not hijack here but can these cylinders be used as air shocks or like nitrogen shocks on a real buggy for adjusability so you could lower or raise the suspension at will I know it can be done I was just wondering if these cylinders will work.

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12-01-2005, 07:37 PM	#36
JasonInAugusta 06 Super National Champ Join Date: Jun 2004 Location: Stark Industries Bar and Grill Posts: 11,361	They won't allow compression or droop once set to a given length. You'd need to mount one vertically in the center of the axle and let the axle rotate around them. That way you could control chassis ride height and still have articulation. Kinda like a stick, only a hair more complicated.

12-01-2005, 08:04 PM	#37
Cole82 I wanna be Dave Join Date: Jul 2005 Location: Cedar Rapids Posts: 2,028	What if you used a Co2 tank instead of air?

12-01-2005, 08:16 PM	#38
RD400 Rock Crawler Join Date: May 2005 Location: omaha Posts: 858	I am totally into the "try something new" thing, but, this system is huge. The tank is 1 1/2 times the size of a beer can. Then when you find a place for all the plumbing and contols this thing is going to be as big as my kids wagon. If you run an on board compressor, even more weight. If JIAs calculations are right (I'm sure they are) you are going to use up all your air by the time you make it over the first rock. If you make it work, great. As for me I will stick with a servo, light, strong, easily replaced.

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