Mr_Byte

No springs internally on RC shocks. I had thought of this after seeing your setup at the last meet.

In looking at a few of my spare shocks laying about the bench, they are all externally "spring'd", with nothing but silicone oil inside. The pistons are generally plastic with 2 or 4 small holes to allow the oil to pass thru, the weight of the oil determines how fast or slow the shock is.

I figure some CA on the holes to seal them, and then drill/tap the cap of the shock. There is sometimes a rubber cap/bulb thing that would need to be removed, possibly replaced with an o-ring to promote sealing between the cap and the shock body. If you needed a 2-way ram, you'd tap both cap and someplace in the side to provide twin chambers, and some fuel line below the piston to keep it from passing the fluid port for the lower/bottom chamber.

Shocks are (relatively) cheap, and one could use a large one at the servo to drive 2 smaller ones at the rudders.

When I build my next hull, gas or nitro remains to be selected, but I am planning on testing this out. With a selection from 1/16th to 1/5th scale shocks available, this would be very cool.

DJLaPalme

Hey greygoose81 how is the hydraulics coming along? Any chance someone could buy a pair of the large cylinders and if so at what price? I would like to set them up on my new big boat. Dennis

crispyspa

Yea...what's going on here? Updates man...updates.

claserdesigns

My Feedback: (14)

Yeah I'm interested too, maybe I could use this on my gas airboats.

greygoose81

These are the cylinders I am working with now. I got side tracked on another project, but I am getting back on it now. I am going to run some tests with these, and if it goes well I will more than likely use them. As soon as I test them I will let you guys know how it went.

DJLaPalme

What is the length of the stroke on the small ones? They look like they would be easier to mount and adjust. Dennis

evader512

This is kinda interesting
could you use like a light Rc car shock oil or something instead of antifreeze

greygoose81

what weight is rc shock oil?

evader512

you can get it in almost anything i run 40wt in my car shocks and thats way thicker than antifreez though so you would have to try thinner. id ask your lhs

evader512

updates man, updates.

greygoose81

I am starting on a new boat and plain to use the hydraulics cylinders that I know work. I want to go over board on this build to show the possibilities of using hydraulics. I will use them on the rudders and throttle and may add an adjustable trim tap. There are some other things I want to do but I got to keep that down low. Don’t want to give anyone a heads up before the next MABA race.

I am working hard to get it all just right. Tried to use some other cylinder but I’m going to need to do some modifying for them to work. But it is coming along slowly but surly. Here is a pic of the cylinder that I will be using.

Mike2735

My Feedback: (3)

What are you using for pressure? What kind of pump and how much pressure? The reason I ask is because I have a few ideas that may help.

crispyspa

I don't think it's a pressure system. It's a simple system without a pump.

DJLaPalme

It works by having one cylinder being operated by your steering servo and one cylinder being connected to your rudders. When the servo moves the piston on the cylinder hooked to it the fluid flows to the rudder cylinder and moves the rudders. Nice clean system. I am planning on using hydraulics on a BIG r/c airboat of mine. It will be using a McCulough 46cc chain saw engine. I will let you know how it works. I purchased the cylinders from Greygoose81. Dennis

greygoose81

any ideas would be wecome. what are your ideas?

Mike2735

My Feedback: (3)

I had an idea to make a small gear pump and let the main engine turn it in a plane. Most of our gasoline engines have a shaft out the back and I thought that would be a way to drive the pump. You really don't need tons of pressure. maybe 100 psi. That should be easy enough to produce with the right lightweight oil. Then you could use a spool valve located anywhere you wanted with a micro servo. The lightweight servos should counter any weight addition from the pump. This is just an idea I have been toying ith for a while.

But from what you are using..Have you tried small air cylinders. They would work fine with lightweight oil. At least I think thet would. Would like to hear how your setup is so I can understand it.

res3567

That is my favorite vodkaLOL!! I knew there was somthing about your username I found familiar!!!!

greygoose81

dose anyone make a pump that small? if they did that would be cool to use on a rc bulldozer or somthing like that.

DJLaPalme

You could use the valve from a retractable landing gear system for the control valve. The only problem is it will not be easy to get the exact amount of rudder throw desired. The valve will only be right/left. You will have to move it to neutral. When I was on subs in the NAVY(Never Again Volunteer Yourself) I spent a few months diving and driving. All our controls were hydraulic/ electric. If you turned the helm say 10 degrees the rudder would move that far and stay there till you turned it in any other direction. I wish I could remember how it worked. If I can remember that would be a perfect system for this. If it could be built. Otherwise the two cylinder system is the way to go. Dennis

dblthunder

hey guys this sounds pretty cool. would be a sweet setr up. but dont forget an important fact. hydrolic oil is used because it doesnt compress unlike many others. atf[automatic trans fluid] is one of these fluids and can be obtained in 5 to 10 weight which would work great good luck

dblthunder

oh an after thought, i may have some rams ,hyd cyl. that may work real well hear. when i find them ill post em so you can try them. this should be easy to make up.ill get back