Rig tension

higgs · Jun 5, 2011

I think the literature that comes with the Loos is probably a good place to start.

SEMIJim · Jun 5, 2011

Rich (P303) said:
Would 15% of wire breaking strength be a good place to start?

Yes. If you have a backstay adjuster/tensioner, as does Abracadabra, then, of course, it will vary. You also want to keep an eye on mast bend. At 15% on the forward lowers on Abracadabra there was too much, I felt, so I backed them off a bit. Also, on boats like Abracadabra, you generally don't want a lot of aft lowers tension, so I generally tension those to only about 8-10%.

Giulietta's Rig tuning instructions - adjust your rig is very good. Also, Ivar Dedekam's Sail and Rig Tuning is a terrific book, that I think every sailor should have on his or her bookshelf.

I re-tune our rig every spring, after we re-step the mast.

To the other readers: You don't have to have a Loos gauge to tune your rig, but it sure helps.

Jim

hutch5151 · Jun 5, 2011

Hall Spars has a great rig tuning guide available online. Also, Jamestown distributors has a U-tube video out on how to tune your rig.

RichH · Jun 5, 2011

15% cap shroud tension on a P303 is std tension. The mast should have a forward 'bow' or 'prebend' of about 3/4" (lower forward @ 18-20% and lower afts @ 10-12%) ... but will sail adequately well with the mast 'straight up'/ no prebend and with 15% on all the lowers (but the boat will then develop slightly more heel and the mast will be vulnerable to 'pumping' at the higher windspeed and while in a slip or at a mooring). Nominal backstay tension @15% will give proper jib luff shape in about 15 kts., less needed in super light wind, much more in heavy winds but not to exceed 25%-30%, 15% is the 'plain vanilla' back stay tension for 'recreational sailing'.

Giulietta's Rig tuning instructions - adjust your rig (see post #3) is 'outstanding' and will quickly get you to a 'plain vanilla' tune.

The 303 has the exact same mast section as the P30, which we actively campaigned and won a ton of pewter. The 303 is a good ol' boat! ;-)

SVCarolena · Jun 7, 2011

Lots of good suggestions here, and I also agree that you should check out Giu's rig tuning guide. On our P303, I stick with 15% all around on the Loos guage. Keep in mind that the lower shrouds are a thicker diameter than the uppers (1/4 vs 9/32), and thus 15% is a little higher than it is for all the other lines. I have the original paperwork at home, but as I recall, I set mast rake at 4 inches at the goosneck (use a halyard and a weight on the end to measure). You won't get much bend out of that mast unless you really torque down on it. Ours has just a very slight bend at 15%. Since I'm not comfortable with more, and it sails fine, that is where we leave it. After we replaced all our rigging and got everything lined up and properly tuned, she sailed like a different boat. Now we have just a wee bit of weather helm, just as it should be. Previously, we had to hang on the wheel in over 10 knots to keep from rounding up. Now that I'm comfortable tunning the rig, I loosen it at the start of winter and retune in spring. keep in mind that once yo have it tuned, you may need to loosed or tigten the rod at the mast below deck - it should be just snug when everything is in tune.

SVCarolena · Jun 7, 2011

Also see RichH's great post here re: weather helm on the P303. I found it very helpful when we first got the boat and were trying to figure out why our weather helm was so bad: http://www.sailnet.com/forums/gear-maintenance/34713-weather-helm-pearson-303-a.html

SEMIJim · Jun 7, 2011

SVCarolena said:
Keep in mind that the lower shrouds are a thicker diameter than the uppers (1/4 vs 9/32),...

Surely it's the other way 'round? It is on our P30. Plus: 9/32 = 1/4 + 1/32

Abracadabra's are 1/4" for the forestay, backstay and cap shrouds, 7/32" for the fore and aft lower shrouds.

Jim