Hello, Gale gave me his e-mail address but it doesn't work. He and his wife rolled over in their "T" and they are O.K. They will be writing a future article on how to rebuild the front end of a Model "T".
What? Rolled over? When did this happen?
Thats not good. Is this the same Gale Garrison that rolled in his 1911 previously in 2011?
This is the same Couple that overturned their T while going around a right hand curve at a moderate speed. The Car went over a bump in the road and the front wheels slammed to a full right turn. They almost had the car stopped when the right side front wheel climbed a ramped curb and the car slowly rolled over.
Both Gail and Jim are doing well and for the most part have recovered from their injuries. The car is being rebuilt and should be on the road this summer if all goes well.
Possible cause for the accident:
The design of the Model T front end is simple but not very safe. For a car to travel straight and not wander side to side, the location where the axis of the king pin intersects the road surface must be forward of the location of where the tire touches the road surface. With the design of the Model T front axle assembly, the king pin intersect is ahead of the tire. It also is to the inside of the tire. When the front wheels are turned to the right, the tire contact spot on the left front wheel is moved forward, reducing the amount the king pin intersect is ahead of the tire contact.
If The car hits a bump and bounces up, it pulls the wishbone pivot up along with it. This reduces the tilt of the king pin which moves the king pin intersect to the rear. Also if the car has wire wheels, they may be mounted farther out, which accentuates the amount the tire contact moves forward during a turn.
It is my conclusion that the cause of the accident was when the car hit the bump and rose up, the left front tire intersect with the road got ahead of the king pin intersect, which caused the steering wheel to be snapped out of the driver's hands. The car did not show any sign of over steer or failed or bent parts. That was the first thing I looked for while at the accident scene.
That happens with early wishbone cars only, Art?
How much can the early wishbone flex? I had a bent one for sale there.
Early wishbone flex could add to the problem but I think the lifting force from the axle pushing at an angle on the spring when cornering is a much bigger contributor. The spindles are about 1/2 inch below the early wishbone mounts on the axle so it would take a pretty good hit to flex or bend the wishbone through the wheels. Bending the wishbone from hitting a stump is more probable. However anything, such as worn parts etc, that lets the tire patch get closer to the king pin intersect adds to the risk of the wheels slamming into the stops.
I have had the wheels on my car uncontrollably wobble from side to side when going thru about 4" of mud at a very slow speed. I think the depth of the mud effectively moved the tire patch ahead of the king pin intersect.
What is needed for our Model T's is an add on non-reversible steering box such as the one Les Shubert is working on.
I have two helpers: a 1937-48 Ford steering box, and a hydraulic shimmy damper which prevents rapid hardovers.