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Hi Dave, An opinion and a friendly critique: I take it that the strung cable, gable-to-gable at the ridge, is intended to be tie-off point for a safety harness that slides along the cable as you progress along the roof from one end to the other. If that's true, I don't think it is a good idea at all. The problem comes about with the force during a fall or slide being applied basically perpendicular to the stretched cable. With that arrangement, the tensile load in the cable becomes extremely high for even very mild fall/slide forces. The load transferred to the cable anchor points also becomes excessive and likely would tear out any reasonable means of attaching the anchors to the gable ends or ridge. In other words, your biggest problem is keeping the anchors from tearing out in a fall. I think such an arrangement would be too risky to rely on. Here's what I have done in the past: Run a rope (I used nylon, 5/8" I think) completely over the ridge and attach it to something substantial that is located at ground level on the opposite side of the roof on which you are working. I used my Oliver 77 drawbar as an anchor. Attach your safety harness to this rope. This arrangement permits any force developed during a fall to be applied directly in tension in the rope and would be much safer, IMO, that the arrangement you describe. If the roof is long, you may have to relocate the tractor once or twice to suit. Of course you want to make sure no idiot starts up the tractor and trucks away with you attached to it.  Rod
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