Drag link straightening

[Ken Buhler]

Allan Bennett's post in the classifieds inspired me to follow through on a year long plan to post this.

I want to share what I have been doing with drag links. I made two tools that work for me. It may take more than one posting. The drag link ends are supposed to be 45 degrees to each other and the faces parallel. Never pound the rod to straighten it as that may work harden it or otherwise change its constitution. First, I use the bench mount jig to straighten the shaft by using a basic black spray paint to shadow, and a long sanding block to show discrepancies, over and over again. The small blocks are moved narrow or wide to match the need for each correction. After I have the rod straightened, I use the frame for aligning the ends. I used some channel iron and all thread to make the frame. One end is fixed (those nuts are always left tight) and the other is for the work. First, to twist the rod rotationally and to parallel the ends, I install the rod and tighten the 3/8" bolts on both ends, I move the outer end nuts touching but not tight. Then I lay it on the bench and twist it to get it flat when relaxed. Then I use the adjustable end nuts to push the rod end out into parallel. I found it is better to push out to parallel the end rather than pull in. You can then switch the mounting to true the opposite end.

[Ken Buhler]

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Now the frame.

[Jerry VanOoteghem]

Nice work. Many don't realize how important it is to have the drag link, (and tie rod too), straight. Any bend can allow the drag link to collapse when highly stressed, like when making a sudden turn to avoid a collision. It never fails that on some of the larger tours, you'll see cars with bent drag links.

[John kuehn]

Wow that’s really good work. Great idea to get it precisely straight! I’ve wondered if the reason they get bent in normal service is the tie rod cup end and tie rod balls get some wear and get neglected before the tie rod really starts to bed. A little slack here and there can’t be good in the long run. Maybe oversteering issues could cause it too besides an accident.

[Allan]

I had no reference to reset the angles between the two ends of the rod when re-fastening the one end. Fortunately, on this 1912 item, the other end is threaded, and the adjustment made, purely by eye as the rod sat on the car. On the later fixed end rods, is there a simple way to make this setting, or is it rarely significant enough to require correction?

Allan from down under.

[Harry Lillo]

Nice work Ken.
How long does it take to correct an average drag link?
Harry Lillo

[Ken Buhler]

Hello Harry,
It can take up to three hours with attention to every detail. I would declare it to be certifiably safe.
Ken

[Ken Buhler]

I had no reference to reset the angles between the two ends of the rod when re-fastening the one end. Fortunately, on this 1912 item, the other end is threaded, and the adjustment made, purely by eye as the rod sat on the car. On the later fixed end rods, is there a simple way to make this setting, or is it rarely significant enough to require correction?

Allan from down under.

Hello Allan,
My frame is designed to correct the rod ends to be at 45 degrees to each other and the ends absolutely parallel. I highly recommend the drag links to be absolutely correct as they are one of the most critical links in the steering. If you would like more clarity, I welcome you to connect directly with me.
Ken