Spindles, tie rods, ball joints - what's bearing the load here?

[akeeton]

Hey guys,

I'm trying to make my own steering knuckle + spindle but have almost no experience.

I'm having some trouble understanding what handles the axial load at the top of a steering spindle.

It looks like for simpler setups it's just a nylon or bronze bushing and the spindle just pushes up against the flange.

What if I wanted something that has less friction? Are ball joints sometimes used at the top of bottom? Are tie rod ends meant to be able to handle that sort of axial load?

If there's a good reference for steering and suspension assemblies, point me to it

 

[KartFab]

ball joints are not a good idea.

'heavy duty tie rods would only be a good idea if you had a double a arm suspension set up

option #1 is the simplest/easiest solution (unless that is you want suspension).

for just a little bit of suspension, without going into A-Arms, you could put a spring above the spindle, and increase the height of the spindle bracket. The kingpin bolt would hold everything together.

Also drilling and tapping a hole in the spindle and putting a grease fitting in there also reduces friction, and is common on a lot of go karts.

 

[anderkart]

You could use spindle bearings like racekarts have: http://www.out2win.com/catalog/steer.html#4

 

[OzFab]

The spindles on my kart have bearings top & bottom with the kingpin bolt through the centre, they're off a race kart so, you would think they'd be good enough...

I'll point you to this thread & suggest you read it thoroughly & completely, it won't show you how to make the spindles but, it will help you get the best handling from them...

 

[Scout]

IMHO a tapered roller bearing would handle the load much better than ball bearings.

 

[firemanjim]

IMHO a tapered roller bearing would handle the load much better than ball bearings.

If I could get a set small enough, I would use the tapered bearing also. If I was going to take the time to do my own set up, I'd start with a tapered bearing set (1top and 1 on bottom) , to fit a 5/8" (or grade 8 , 1/2" ) bolt. Next, I'd take some 1&1/2" x3/4" ID bar stock and bore it out on each end to accept the bearing properly. Next, I'd drill an tap the center of the OD to accept a grease zirk. Next would be to weld on the spindle at the appropriate angle , 90* from the grease zirk. The last step would be to weld the control arm onto the body, 180* from the grease zirk, and at the appropriate angle to match the spindle bracket /steering geometry.....
Imma dummy though, so this might not make sense......

 

[rockman96]

IMHO a tapered roller bearing would handle the load much better than ball bearings.

That is the final word as for strength... Timken style bearings carry everything from the weight of a car, to the torque pulses from a stroked Harley and more. Might be a bit of overkill on a kart, but I like overkill, it means you don't have to worry about it failing.

This being said, I fabricated my own spindles and used regular roller bearings on 1/2" shoulder bolt kingpins, with 5/8" shoulder bolts for the wheel bearings. Working great so far.

 

[OzFab]

Good to hear; you did include Ackermann, didn't you?

 

[rockman96]

Good to hear; you did include Ackermann, didn't you?

Me? Yes, put it all rearward whereas it was in front originally. If you weren't talking to me, sorry... just ignore.

 

[OzFab]

Yes, I was Again, good to hear

 

[chancer]

Spindle bearings

This being said, I fabricated my own spindles and used regular roller bearings on 1/2" shoulder bolt kingpins, with 5/8" shoulder bolts for the wheel bearings. Working great so far.[/QUOTE]

How did you make those spindles?

 

[Half-breeder]

Hey guys,

I'm trying to make my own steering knuckle + spindle but have almost no experience.

I'm having some trouble understanding what handles the axial load at the top of a steering spindle.

It looks like for simpler setups it's just a nylon or bronze bushing and the spindle just pushes up against the flange.

What if I wanted something that has less friction? Are ball joints sometimes used at the top of bottom? Are tie rod ends meant to be able to handle that sort of axial load?

If there's a good reference for steering and suspension assemblies, point me to it

I have only seen/used 2 different kinds of tierod ends... we call em type A and type B... (links provided).

I have found that type B is a 'stronger' setup where as type A is a more conservative (doesnt utilize much space).

In the drawing, in setup #1, the nylon bushings are used for several reasons. They fill in most all the 'gap' that the King pin should happen to not utilize. They provide a considerable amount of 'slip/slide', being made of a smoother material than metal, it will tend to allow ease of movement. They diminish rattling in steering/suspension upon sudden impact/road vibrations. Out of the 3... #3 would work aswell... however, the cost effectiveness of said tierods, the ones that 'would' work, would not equate to the cost effectiveness of fabrication on a kart/buggy. IMO, I suggest upon setup #1 to go by, asfar as a fabrication 'plan'... stronger/better/cheaper/less moving parts.

... also... did you take caster/camber into consideration? Guess it all depends on the speed your gonna travel as to whether or not they'll be needed.

 

[chancer]

In figure 1 of the above plans it shows a nylon bushing. I have one kart where I implemented a bronze bushing. My other kart currently the spindle and spindle bolt have been metal to metal and are worn out. I am fabricating new spindles and want to use some sort of roller bearing. 5/8 spindle bolt and 5/8 axle.
Any suggestions on how to do this.? DIY and on a budget.