Tube axle on a T bucket
- Thread starter Neshkoro
- Start date
Lee_in_KC
Active Member
By the way, aircraft standards would say that you should mount the tie rod end above the steering arms so that if the nut backs off, the shank of the tie rod end would still lay in the steering arm from gravity, theoretically allowing you to safely steer to the side of the road. They don't say how you detect that the nut has fallen off. 
Aircraft standard for aligning bolts... bolt should be aligned so that gravity or thrust will tend to keep the bolt in its hole. So the shank of the bolt should either point downward or rearward.
Aircraft standard for aligning bolts... bolt should be aligned so that gravity or thrust will tend to keep the bolt in its hole. So the shank of the bolt should either point downward or rearward.
EX JUNK
Moderator
For one thing, the Ackerman is reversed but that will not cause it to wander. However, from what I can tell in the pictures your caster is not set correctly. Have you even tried to measure it with an inexpensive degree level? Here is a link that you should check out: http://www.nationaltbucketalliance.com/tech_info/chassis/shimmy/shimmy_help.asp
Jim
Jim
GAB
Member
Lee,
Here is what I used for a jig to build the axles. Just used a pair of these that bolted to a piece of channel. Machined the kingpin bosses and kingpins, bent a piece of 1-3/4" x .188" tube, notched it and welded it together. Instant Axle! :lol:
I won't make you post a pic of the coilover tool....I'll do it for you! :lol:
Here is what I used for a jig to build the axles. Just used a pair of these that bolted to a piece of channel. Machined the kingpin bosses and kingpins, bent a piece of 1-3/4" x .188" tube, notched it and welded it together. Instant Axle! :lol:
I won't make you post a pic of the coilover tool....I'll do it for you! :lol:
Neshkoro
Well-Known Member
I will get more pictures as soon as I can. I was in a hurry and just snapped a few this morning on my way to work.
The spindles are from '52 Ford. I cut the ends off the king pin bosses off the suspension and welded them to the tube axle.
I built the camber into the welded tube axle at about 1 or 2 degrees. The caster is set at about 2 degrees positive, or out on the top, and the toe in is around 3/16" .
It has a pretty long drag link because the steering box, from a 1966 Impala, is mounted almost directly under the mostly vertical steering column.
I will take the advice and move the bolts around to help keep things tohgether in case of a failure.
Thnat's abouyt all I can tell you guys about the car.
Thanks
The spindles are from '52 Ford. I cut the ends off the king pin bosses off the suspension and welded them to the tube axle.
I built the camber into the welded tube axle at about 1 or 2 degrees. The caster is set at about 2 degrees positive, or out on the top, and the toe in is around 3/16" .
It has a pretty long drag link because the steering box, from a 1966 Impala, is mounted almost directly under the mostly vertical steering column.
I will take the advice and move the bolts around to help keep things tohgether in case of a failure.
Thnat's abouyt all I can tell you guys about the car.
Thanks
EX JUNK
Moderator
If, as you state, that the caster is 2 degrees out at the top, you mean that it is leaning forward at the top then you are definitely wrong. It should lean back at the top between 5 - 7 degrees as I stated in my first post. With the forward tilt the car will tend to wander and follow even the smallest undulation in the road.
Jim
P.S. That 5 - 7 degree measurement should be taken with the car sitting on a level surface and at ride height.
Jim
P.S. That 5 - 7 degree measurement should be taken with the car sitting on a level surface and at ride height.
donsrods
Member
Actually your setup is much better than I expected........usually homebuilt axles and odd spindles look, well, homemade. I like the way you did it. But I see exactly what everyone else saw..........your caster is non existent. So that we are all on the same page, here are the correct terms.
Camber................the amount your tires lean in or out at the top when viewed from the front.
Toe in or out..........The amount your tires lean in or out when viewed from the top. Toe in would be with the front of the tires closer together than the back and toe out is the opposite.
Caster................the amount that your kingpin leans back at the top when viewed from the side. (think bicycle front fork, that is positive caster) You want yours to lean back somewhere between 4-9 degrees typically, but every car likes a different amount.
Tie rod............the rod running between the two wheels.
Drag link..........the rod running from your steering arm on the box to the steering arm on the wheel.
Not trying to offend anyone by posting that, but we do occasionally have some folks just starting out in this hobby who may not be sure.
On your car the lack of positive CASTER will for sure make it want to wander. If you took a shopping cart front set of wheels and made them mount straight up and down instead of leaning back, they would not track, each wheel would be fighting the other one. That is what you have going on, I think.
Go to the hardware store or Home Depot and buy a $ 10 angle finder with a dial inside the glass, so that when you lay it atop something (like your kingpins) it will tell you how far off level it is. That will tell you what you have for sure.
But in the pictures it sure looks like very little or no caster.
Don
Camber................the amount your tires lean in or out at the top when viewed from the front.
Toe in or out..........The amount your tires lean in or out when viewed from the top. Toe in would be with the front of the tires closer together than the back and toe out is the opposite.
Caster................the amount that your kingpin leans back at the top when viewed from the side. (think bicycle front fork, that is positive caster) You want yours to lean back somewhere between 4-9 degrees typically, but every car likes a different amount.
Tie rod............the rod running between the two wheels.
Drag link..........the rod running from your steering arm on the box to the steering arm on the wheel.
Not trying to offend anyone by posting that, but we do occasionally have some folks just starting out in this hobby who may not be sure.
On your car the lack of positive CASTER will for sure make it want to wander. If you took a shopping cart front set of wheels and made them mount straight up and down instead of leaning back, they would not track, each wheel would be fighting the other one. That is what you have going on, I think.
Go to the hardware store or Home Depot and buy a $ 10 angle finder with a dial inside the glass, so that when you lay it atop something (like your kingpins) it will tell you how far off level it is. That will tell you what you have for sure.
But in the pictures it sure looks like very little or no caster.
Don
Ted Brown
Member
I guess you probably called it the Happy wonder all these years... remember this also, too much toe in causes wheel wobble also, no more than 1/8" at the max, and that amount usually goes away while driving, tires want to pull back under rolling load, but also remember that a T has almost no weight on the front tires, compared to a stock type car, hence less toe is needed... Just my thoughts.. 
GAB
Member
One other thing that might enter into this situation is kingpin inclination. That is the angle of the kingpin in relation to the plane of the center of the tire. The ideal is for the line through the kingpin to intersect the ground at the same point that the plane of the wheel does. Few, if any, cars achieve this ideal. Instead of the wheel and tire pivoting on one point, it rolls around the point that the kingpin describes.
The pics don't show well enough if the kingpin is inclined or if it is perpendicular to the spindles bearing centerline. If it is that way, it would mean that the radius that the tire rolls about when encountering road deviations is pretty large and consequently it would have more leverage against the parts that are responsible for maintaining a straight ahead direction.
It looks like the original upright to which the spindle attaches has been trimmed and welded to the notched end of the axle tube. I'm inclined to think that the kingpin is pretty close to perpendicular to the ground.
This is just some guessing on my part. Looks like it might be a combination of several things contributing to the problem.
The pics don't show well enough if the kingpin is inclined or if it is perpendicular to the spindles bearing centerline. If it is that way, it would mean that the radius that the tire rolls about when encountering road deviations is pretty large and consequently it would have more leverage against the parts that are responsible for maintaining a straight ahead direction.
It looks like the original upright to which the spindle attaches has been trimmed and welded to the notched end of the axle tube. I'm inclined to think that the kingpin is pretty close to perpendicular to the ground.
This is just some guessing on my part. Looks like it might be a combination of several things contributing to the problem.
George, are you talking about "Scrub Radius?" Here is a picture I swiped from the net showing positive scrub radius with a strut type suspension, but the idea applies to king pin solid axle cars as well:
A lot of positive scrub radius was originally put into older heavier cars from the factory to make them easier to turn the wheel when the car was sitting still. Instead of the tire fighting to turn on the center of it's contact patch, the large scrub radius would allow the tire to roll around on that radius instead.
The club racers I know are always trying to get to the ideal place of zero scrub radius. They say that positive scrub radius makes their light weight cars do funny things when they encounter rough terrain on the track.
My attempt at making a contribution.
David
A lot of positive scrub radius was originally put into older heavier cars from the factory to make them easier to turn the wheel when the car was sitting still. Instead of the tire fighting to turn on the center of it's contact patch, the large scrub radius would allow the tire to roll around on that radius instead.
The club racers I know are always trying to get to the ideal place of zero scrub radius. They say that positive scrub radius makes their light weight cars do funny things when they encounter rough terrain on the track.
My attempt at making a contribution.
David
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