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  Topic Review (Newest First)
02-27-2013 01:10 PM
Re: Pearson 30 rig tuning

If your boat has been on the hard for 2 years, I suggest taking it slow. The stays will stretch, and the hull will flex. So make some adjustments, then check on them a few days later, and after any heavy sailing. Like a guitar or other stringed instrument, it takes a while to get it really well tuned.
06-28-2012 11:54 PM
Re: Pearson 30 rig tuning

Downloaded the Selden Guide, very comprehensive. It's still a bit daunting, but I'm a see it done once and I've got it person....or just do it (it will take me alot longer alone but it will be a learning experience). When I bring it up from Rock Hall to HDG area I'll let you know and if interested you can come see her. She's not a beauty queen, but not a disgusting looking gal either. The old powder/royal blue topsides which might get changed to white this winter. I put in new through hulls, 2 from the old head (original 1970's vintage and a new ST40 speed/temp transducer/mount. Already have the ST40 Depth. Installed 20A Charles Battery Charger, auto bilge pump, had all deck hardware rebedded, had bottom blasted to gelcoat - 2 coats of barrier coat, 3 coats bottom paint, red/med blue/midnight-navy blue final. New 7/16" VPC Jib Halyard, new 1/2" StaSet Jib/Genoa Sheets, new StaSet travellers. Topsides cleaned until my arms fell off but former owners docked "by braille", I think.
Anyway, I think she's looking ok and can't wait to sail her. A friends husband has a J30 and won the Chesapeake 1999 Championship, so he's also a good potential "hands-on" help if I can compete with his rowing schedule. If available, he may help me sail her from Rock Hall, so the re-adjustments...I'm sure he'll know his way around.
Thanks for the help...will keep you posted. Cheers!!
06-27-2012 11:09 PM
Re: Pearson 30 rig tuning

What Shaw meant was the mast should be straight up or 90° to the horizontal with little to no mast rake.

The OEM P30 mast without a 3/4" prebend ....
1. can easily develop 'mast pumping' at low wind speeds from the aft quarter ... the prebend changes the natural frequency of vibrations of the mast.
2. Sails made by a 'good' sailmaker will be already cut expecting that 3/4" mast prebend. Without the prebend the sail will set with more draft than needed .... prebend 'flattens' a mainsail. A P30 on the Chesapeake's normal conditions (10-15kts w/ 1-2ft of chop) will be much 'faster' and with less heeling with slightly flattened (speed shape) mainsail.

06-27-2012 10:42 PM
Re: Pearson 30 rig tuning

Originally Posted by Robcooper0767 View Post
I guess my rookie, uninformed question is: How do I know the percentage? Do I need to buy a Loos guage, or is it a combination of friendly fellow sailors who help and learning by doing?
Thanks again for the info. I'm printing this one out and taking it to where I bought her in Rock Hall, where I had some of the more complicated modernizing done. I want to have it done right the first time, and watch, learn, and participate.
Easy WITHOUT a gage. Seldén has the best and most comprehensive mast tuning guide on the internet.
Go to:
and download item: "Hints and advice" (7390 kb) 595-540-E ¤en .... its the Seldén Mast Tuning Guide.

Then for accurate tension measuring WITHOUT A TENSION GAGE, Go to the manual and look up “The folding rule methodpage 29 ... but youll need a steel tape measure divided in 'meters, cm and MILLIMETERS.

Good luck. Make that P30 'fly'. ;-)
06-27-2012 10:36 PM
Re: Pearson 30 rig tuning

@ SVCarolena and Rich H:
A bit of confusion here. Some (most) say have a little bend in the mast, but Bill Shaw says straight mast, and he mentions the 10M and P30. Since he designed the boat, I've got to give him the nod, you have bend or straght? And, aside from bend being the norm, what about for a P30?
The guy at the boatyard said most masts are tuned to have a little aft bend toward the stern. Am I just getting all the facts confused with too much data, or missing the point completely?
06-27-2012 10:11 PM
Re: Pearson 30 rig tuning

All I can say is Wow! And have provided exactly what I was looking for, relating to a P30. I narrowed it down to a CAL 31 and P30 after deciding we needed a bit more cabin headroom (wife is 5'10") for comfort, but wanted a older "racer/cruiser" - combination of wallet limitations and desire to "move" competitively. Must be related to reason I owned an MGB too (miss it!).
I guess my rookie, uninformed question is: How do I know the percentage? Do I need to buy a Loos guage, or is it a combination of friendly fellow sailors who help and learning by doing?
Thanks again for the info. I'm printing this one out and taking it to where I bought her in Rock Hall, where I had some of the more complicated modernizing done. I want to have it done right the first time, and watch, learn, and participate.
06-27-2012 05:57 PM
Re: Pearson 30 rig tuning

I used to race a P30. For the best output set the capshrouds at 15%, the forward lowers at 18% and the aft lowers at 12%, Initially set the backstay at 15%.

the 18% forward lwr / 12% aft lower tensions will give the mast a correct 'pre-bend' (forward bow) of approx. 1/2" .... the approx 1/2" forward bowing is important no matter what tension is in the rigging.

Then go sailing on a hard beat in approx. 15 kts. to be sure the mast stays straight and without any side bowing. Make corrections as needed.

To set the correct tension in the backstay according to the day's conditions: .... but no more than 30% tension for long periods of time. When done sailing for the day, reduce backstay tension to ~15%.

FWIW - a boltroped dacron mainsail on a P30 requires about 3 extra inches of luff stretch via the main halyard to attain correct sail shape. Raise the main full up, then apply approx 3 inches of extra halyard strain.
You want the P30 set up so that you get only very 'slight' so-called weather helm ... or about needing only 3° of rudder angle to keep the boat on a hard beat in 15kts.
Here's the correct way to raise a dacron mainsail on just about any boat: How to properly RAISE a woven dacron mainsail -
06-27-2012 05:44 PM
Re: Pearson 30 rig tuning

Thanks for the websites. "Passeggiata" was too long on the hard and probably unstepped in the past (some evidence). Since I have never done this before, I want to learn, but the terms and complexities, when written, sound a bit detailed. But, I might watch someone do it the first time, and learn. I'm finding so many options and different recommendations based on specific boats and racer vs. cruiser when I webcrawl......alot of data. I do want performance but I won't formally race this year. Think I should "learn" her first.
I've got a 100 (dacron - almost new - with racing battens), 150 (a bit long in the tooth), 160 drifter (mylar - almost new) and fully battened main (neither old or new).
Whether all that sail info matters, I don't know.
But, again, I'll check out the sites you gave. I want to move her from Rock Hall, MD to her permanent slip near Havre de Grace area in a few weeks and want to have this done before I take the long, first "real" sail.
Thanks for your help.
Best Regards, Rob
Passeggiata - Pearson 30, #644
06-27-2012 04:39 PM
Re: Pearson 30 rig tuning

We replaced all the rigging on our P303 and for tuning I used the advice from the following sources. The first is an article that Bill Shaw wrote. The other is from a former member of SN who now runs and posts at He also runs a race boat. We use a Loose guage, which is nice for getting the tension right but is not necessary, but the rest of it is just measuring and sighting up the mast, then going sailing:

Rig tuning instructions - adjust your rig
06-27-2012 03:11 PM
Pearson 30 rig tuning

Hull #644, Passeggiata, has been launched for the first time in 2+ years last Friday! We bought her last fall and I'm looking for recommendations on Specs for rig tuning. Old websites, ie. Bill Shaw, etc, are no longer valid. Anyone have Spec advice for standard, single set of spreaders 1974 P30 setup would be appreciated.
Best Regards, Rob
Passeggiata - Pearson 30, #644

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