Home Brew Steering

[wendle]

Originally Posted by JimmyB

I am unsure how the setup works for setting the lock to lock and also the travel of the ram? I that based on the orb?

nah, the orbital will keep extending the ram as long as there is more ram to extend.

the easiest way to do it with an ag type clevis ended ram (if you can physically fit it in the right position) is to mount the ram so that at full extension you are a millimetre or so of one steering stop. then steer the axle so you are a millimetre off the other stop, measure the exposed amount of shaft left, machine a spacer out of delrin or uhmwe (old body lift block), unscrew the clevis off the shaft slide the spacer on, then screw the clevis back on. you now have exactly the right amount of shaft throw.

if you don't have that much room, you can mount the ram so that at full compression you are a hair off one steering stop, then weld a nice big lug onto the axle housing to stop the ram mount on the tie rod at the right amount of extension.

obviously the best way is to have a ram that is already the exact throw you need, but you already have a ram, so either of those methods will work for taking the load off the rest of the system.

the setup on my first buggy wasn't limited, and that in conjunction with the ram being about 15mm off parallel with the tie-rod used to fatigue and stress a lot of stuff.

[FireTruck]

the way I did it was when I git my high steer arms they were un-drilled... and we drilled the holes in the steering arm so that the steering left to right was where I wanted it, and the ram hit the end of it's travel in both directions at the same point.

If you hit your steering stops before your ram is fully extended, it can rip your knuckles off let alone your steering stops...

And return to centre doesn't mean that when you take your hands off the wheel it goes back to centre... it means that it is just like regular power steering. If you are moving at speed and you take your hands off in the middle of a turn it will return to centre as long as your wheel alignment (and castor) is OK.

If you turn when stationary and take your hands off it will stay wherever it is pointed.

My cylinder is an 8" travel jobby - that is the most common length used.

S.

[Jimmyb]

That brings another question Wendle, does the ram need to be parallel to the tie rod? I have heard that it does to prevent stress on components.

[wendle]

Originally Posted by JimmyB

That brings another question Wendle, does the ram need to be parallel to the tie rod? I have heard that it does to prevent stress on components.

yep. as close as you can get it. in the horizontal plane it will never be perfect as the tie-rod moves closer and further form the axle housing as the steering cycles, i split the difference when i mounted up my new one. in the vertical plane there is no reason it can't be spot on.

[wendle]

Originally Posted by FireTruck

My cylinder is an 8" travel jobby - that is the most common length used.

you must have some awesome steering lock. i am only using 8" of ram on a unimog axle.


do you get any reactive steering if you say force one tyre at half steering lock into a vertical ledge while the other front tyre is cruising on easy ground?

[FireTruck]

The steering lock depends on how far out on the steering arm you drill the hole (or how far out the hole is you are using)... I got my steering arms un-drilled and put the holes where I wanted it.

I was going to go for a 7" stroke and drill the holes closer in, but Sean (station on POR) talked me into going for 8" as that is what most people are using and it would give me better force with the arms drilled out further.

You do get some 'feel' if one or both of the tires is under stress trying to turn them one way or the other... same as any power steering setup... but the 'feel' you get is very subtle (unlike most regular power steering setups).

It kinda helps to feel the terrain that you can't see, but the hydraulic force is waaaaay more than any outside force trying to overcome it!

S.

[FireTruck]

oh, and you can steer the system while the engine and/or pump are not running... this is because the steering valve acts like a little pump. It is hard work, but you can still steer. Pretty similar to when the engine is off for regular power steering.