Adjustable Drag Link

A couple years ago an article about how to make one by Wiley Higgins (sp) was in the MAFCA newsletter

This is what I could find

http://modelafordclub.co.nz/wp-content/uploads/Aligning-the-Model-A-Gemmer-Steering-Box-Aug-11.pdf

..

I think this article is a bit misleading. Changing the length of the drag link is not the best way to set up the steering /alignment.

Here is a quote from the link:
Aligning the Model A Gemmer Steering Gear for Straight Ahead Driving by Wiley Higgins; *******, GA
If your Model A is equipped with a Gemmer 2-tooth steering gear, the steering wheel should make a perfect “X” when you drive the Model A straight ahead. The spokes should not obstruct your view to the dash panel.
The Gemmer steering gear has about three turns lock to lock. A correctly adjusted Gemmer 2-tooth steering gear will have the tightest adjustment at center. “Center” is indicated when the steering wheel keyway is exactly on the top, or about 1 ½ turns from left or right lock.


You want to keep the wheel at the point of tightest adjustment. Changing the length of the drag link takes the wheel off center in relation to the steering gear. It should not be changed.
When you align the toe-in the steering wheel should first be placed in the center position. Then any adjustments to the tie rod should be made on both ends equally. Then when you drive down the road in the test drive, if the steering wheel is no longer centered you have to readjust the tie rod, not the drag link. This will ensure the tightest steering. Changing the length of the drag link is not a good idea.
 
You want to keep the wheel at the point of tightest adjustment. Changing the length of the drag link takes the wheel off center in relation to the steering gear. It should not be changed.
When you align the toe-in the steering wheel should first be placed in the center position. Then any adjustments to the tie rod should be made on both ends equally. Then when you drive down the road in the test drive, if the steering wheel is no longer centered you have to readjust the tie rod, not the drag link. This will ensure the tightest steering. Changing the length of the drag link is not a good idea.

Am I missing something? How do you change the position of the steering wheel in relation to the wheels by adjusting the tie rod? The position of the left front wheel is still dictated by the solid drag link. The only way (that I see) to change it is with an adjustable drag link.
 
adjust one end of the tie rod but not the other would do it, keep wheel centered then adjust either side till toe is correct and it goes straight.
 
adjust one end of the tie rod but not the other would do it, keep wheel centered then adjust either side till toe is correct and it goes straight.

Sorry, but the solid drag link would keep the relationship of the steering wheel and the left spindle the same no matter what you do to the tie rod. In what you suggest all you did was move the tie rod. The tie rod adjusts the relationship of one wheel to the other, not the relationship of the wheels to the steering wheel.
 
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Sorry, but the solid drag link would keep the relationship of the steering wheel and the left spindle the same no matter what you do to the tie rod. In what you suggest all you did was move the tie rod. The tie rod adjusts the relationship of one wheel to the other, not the relationship of the wheels to the steering wheel.

Y-Block is correct, you will spend a lot of time moving the Tie Rod only to find you are back where you started, adjusting the Drag link there is a fine balance in getting the steering to hit the wheel stops equally and having the wheel straight, especially with a Double A with the 20 x 600 wheels and tires, I have a plan to draw a simple schematic to explain what moves when changes are made.
 
Seems to me the easy way to make one is buy a complete original tie rod with ends on it. Buy one die for one end. Cut the tie rod off on one end, thread it, install the end that was on it. Should I make some? I have many good used tie rods. If these would sell, I will make them. Your thoughts?

Steve @ Bert's
 
I agree with Y-Blockhead and Brian T. The reason this adjustment is needed is that the steering arm on the left front wheel has been bent somewhat. That will also affect toe out on turns as well. There doesn't seem to be any way to measure this without a spec. measurement of "ball to backing plate" distance. If the drag link end is threaded on one end only, the adjustment would only be in increments of a single thread count (single revolution). An adjustment for sure, but often you'll be caught in the position of needing a 1/2 turn. Quite a number of other factors can also cause the offset in the sweet spot of the sector and worm. A truely adjustable drag link would be a good thing but having the ability know if the steering arm is spot on would also help avoid issues. Also, I believe that the steering arm had a design change ie. early and late - another issue if it was to correct a toe out on turns issue.
 
Seems to me the easy way to make one is buy a complete original tie rod with ends on it. Buy one die for one end. Cut the tie rod off on one end, thread it, install the end that was on it. Should I make some? I have many good used tie rods. If these would sell, I will make them. Your thoughts?

Steve @ Bert's

Steve, that is exactly how I made mine. So simple. You should do a few and see how they sell. Just my thought.
 
Seems to me the easy way to make one is buy a complete original tie rod with ends on it. Buy one die for one end. Cut the tie rod off on one end, thread it, install the end that was on it. Should I make some? I have many good used tie rods. If these would sell, I will make them. Your thoughts?

Steve @ Bert's

As for how they would sell, I made 2, 1 of which I installed when I fitted my reconditioned front end along with the short pitman arm, I had the second one for sale here and it was a little over a year before it sold.
I prefer the using a drag link with a adjuster sleeve over using tie rod ends as there can be a clearance problem with the axle, due to the clamp bolt.
 
Seems to me the easy way to make one is buy a complete original tie rod with ends on it. Buy one die for one end. Cut the tie rod off on one end, thread it, install the end that was on it. Should I make some? I have many good used tie rods. If these would sell, I will make them. Your thoughts?

Steve @ Bert's

Hey Steve,
Yup, just take an original tie rod from the 'stuff' pile, clean it up ...inexpensive :)
Here's where the expense comes in (forgetting your time used to make). Went to a machine shop tool supplier and paid $35. for quality left hand threader. Finished product works very nicely !
You can even loan the LH tool to others to make their own. Cheap enough for one adjustable rod, but when will the LH tool ever be used again...ebay :D !
 
I agree with Y-Blockhead and Brian T. The reason this adjustment is needed is that the steering arm on the left front wheel has been bent somewhat. That will also affect toe out on turns as well. There doesn't seem to be any way to measure this without a spec. measurement of "ball to backing plate" distance. If the drag link end is threaded on one end only, the adjustment would only be in increments of a single thread count (single revolution). An adjustment for sure, but often you'll be caught in the position of needing a 1/2 turn. Quite a number of other factors can also cause the offset in the sweet spot of the sector and worm. A truely adjustable drag link would be a good thing but having the ability know if the steering arm is spot on would also help avoid issues. Also, I believe that the steering arm had a design change ie. early and late - another issue if it was to correct a toe out on turns issue.

100IH, This brings up some good points, I have often wondered how many steering arms are checked in a jig to see if they are bent, or conform to the updated arms as per the Service bulletins,before being re-balled.
The left steering arm I removed from my truck was bent a little over 1 inch from the back plate causing toe-in wear on the right front tire, the right side was about 1/4 inch, I suspect someone maybe using it the same way.
 
I used a tie rod that got bent in the middle. Cut it too length and reused the reversed thread side and used a regular die on the other. Cheap to do and was able to repurpose an otherwise bad part.
 
Sorry, but the solid drag link would keep the relationship of the steering wheel and the left spindle the same no matter what you do to the tie rod. In what you suggest all you did was move the tie rod. The tie rod adjusts the relationship of one wheel to the other, not the relationship of the wheels to the steering wheel.

doh... as soon as i read that then remembered how the model A is setup i knew i goofed...modern cars with rack and pinion you can adjust away to center the wheel...:rolleyes:

oh well brainfart it was...:p
 
doh... as soon as i read that then remembered how the model A is setup i knew i goofed...modern cars with rack and pinion you can adjust away to center the wheel...:rolleyes:

oh well brainfart it was...:p


Me too. I was thinking of the more modern setup instead of the Model A.
I'm now lost in the woods that I slinked back into.....
 
As far as knowing if the steering arm is bent, I think the best thing one can do is to try to have the ball to backing plate space, left and right equal. I tried 3 and got the best match, the others were all over the map. At that point, you are ready to find whether or not you need to buy or build a drag link.
Cooter, excellent point. I haven't cut either apart but I think that the tie rod is hollow with plugged ends to hold up under the clamping force at the socket ends. Those of you who have first hand knowledge, please chime in. This would be a safety issue. Let us resolve it here now for everyone's benefit.
 
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I started this thread a long time ago. If I was going to make 2 more adjustable drag links, what is the drag link diameter and thread size? I would be using one of the tie rod ends on the drag link- with the normal hand thread to make it easier to find a die for the cut off part of the drag link. It might be easier to just buy one or two.

Vic
 
I started this thread a long time ago. If I was going to make 2 more adjustable drag links, what is the drag link diameter and thread size? I would be using one of the tie rod ends on the drag link- with the normal hand thread to make it easier to find a die for the cut off part of the drag link. It might be easier to just buy one or two.

Vic
Vic,
The 2 adjustable drag link diameters I have are, 9/16x18tpi and 5/8x18tpi, you will need a drag link of 11/16 diameter (if there is one ) to use a tie rod end, you will need a left and right to be able to adjust full lock and align the steering wheel, if you go with the drag links use the 5/8 diameter, you will only need the 1 pair of dyes.
 
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