Rig Tuning Tips
> I broke down and bought (~$150 @ Defender) the PT-3
gauge to "tune" my rig (1994,
> surprised to see that the guide posted on the website is much looser than where my previous owner had it. The only thing that stayed
> similar were the cap's, but the rest of the rig was loosened quite a bit. I assume I'll have to track down the author of the guide (Mark
> Yeager from either Dallas or Colorado.), but I wanted to see if anyone had experienced this tuning:
>
> Questions:
> 1. I believe the forestay is already 3" longer with the Hood furler vs. the Schaefer. I assume this means that I don't need to lengthen the forestay?
> 2. Should the backstay be slack with the settings on this tuning guide? Mine still have quite a bit of tension, but I held off from loosening them.
> 3. What adjustments (if any) should be made for different winds?
> 4. How slack should the leeward shrouds be in different wind conditions while beating?
>
> Thanks in advance,
>
> Chris
> Amore #139
To answer your questions (partially):
1. Can't help you.
2. From what I recall of Mark Yeager's emails, the backstay should be pretty close to slack, if not completely, at the default settings. He
was assuming you had an adjuster to tension the rig for upwind work or waves. The ability to slack the rig fore/aft for downwind / light air
was the most important part of his tuning advice I thought.
3. The only control you will use while sailing is the backstay adjuster, which is used primarily to control forestay tension.
Generally you want more tension as the wind comes up, and when beating, in order to avoid excessive headstay sag. The fullness in the jib that
comes from a slack rig. Is good for light air and downwind. If you are in waves you want to keep enough tension to prevent the rig from pumping.
4. Shrouds and spreaders are designed to keep the mast upright and in column and any additional tension beyond what is needed to do that only
shortens the life of the rigging and compresses the mast into the deck, possibly damaging the boat. So don't overdo the shroud tension. That said, the leeward shrouds should never be completely slack. If they are then the rig will be subject to shock loading when you tack or jibe (or roll heavily on waves), which is also hard on the rig. But neither should leeward shrouds be very tight in any kind of breeze when sailing upwind. If they are then the rig is too tight. Things are a bit more complicated if your spreaders are swept back significantly as on a Hunter, or if you are trying to use the lower forward shrouds against the backstay to induce mast bend. But the 320 doesn't have a very bendy mast, and I don't bother.
5. You didn't ask, but I highly recommend Brion Toss's video on rig tuning. You can buy it at briontoss.com.
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T. Scott Thompson
sthompson@toad.net