PA Steering upgrade?

[RedSledTeam]

Originally Posted by ful-rac

Yes it breaks right at the grommet. If you havent yet, you should at least inspect the steering line where it rides thru the grommet for wear, and repair if needed. I think this problem mainly seems to be assosiated with PAs that have the steering tension knob. When you got that tension knob cranked down for that nice tight steering everybody likes....it really starts to wear on that grommet.

Tony,
To understand your issue better, I acquired a PA14 and had my resident Junior engineer-in-training evaluate your problem with the steering cable failure...
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Here is Rockin’ Rolan with his eye on the problem… After thorough inspection of the steering cable system and geometry, we found the following suspect failure areas...
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The probable cause of failure is the contact friction-abrasion on the spectra caused by the angle of the cable as it relates to the fer rule/hard grommet. Furthermore, when tension is increased, the side-effect (pun intended) is increased abrasion exacerbated by higher tension-ing of the spectra cable (think of a bow-saw).
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Your suggestion of an ultra-smooth ferrule would last longer, but still may cause friction in the long run. Further we have determined the root cause of the failure is the linear direction of the cable going from the pulley to the rudder post bell crank. The existing angle causes friction at the ferrule/grommet. This geometry acts like a cable saw on the feed-through ferrule. Problem is the ferrule material is harder than the spectra cable causing contact abrasion and wears down the spectra first . If you can change that angle with an extra pulley etc., we at Redsledteam think it will resolve the problem.