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  #11  
Old 12-16-2011
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Quote:
Originally Posted by jameswilson29 View Post
On my P29, the area is starboard aft of the keel forward of the aft cabin bulkhead. I may be able to access it under the sink or the starboard cabin berth locker. Here are some more photos: SailNet Community - jameswilson29's Album: Winter repairs: hull indentation .

I believe the thru-hull in the photos is the galley sink drain (icebox drains into the bilge).
That DO look kinda big for a jackstand dimple. Treilley is right - clean the bottom paint off and see what's what on the outside before anything else.
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  #12  
Old 12-17-2011
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Thanks for your responses. I will post some additional photos as I investigate and repair.

(By the way, I think a larger area would more likely indicate hull deflection, while a smaller, less gradual, indentation would more likely indicate structural damage in a specific area. This is exactly the same "hollow" area where Pearsons are known to deflect with improper jack stand placement.)

Last edited by jameswilson29; 12-17-2011 at 07:23 AM.
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Old 12-17-2011
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My Morgan OI41 had an area very similar to yours. The indentation disappeared by the next haulout. It was probably caused by uneven stresses on the hull while sitting on it's keel, held up by stands. Once in the water, it went back to it's proper shape.

It's possible that your hull has some degree of hydrolysis. Fiberglass can deteriorate from water intrusion over time and become less stiff. This can lead to indentations from stands or areas such as yours. Whether it is from too thin a laminate or a laminate that has become less stiff it could be repaired, but not on land.

Put it in the water, dive to verify that the area has gone back to normal. Then open some "windows" in your liner if possible. saturate some 3/16" coremat with epoxy and lay them in the suspect area. A few layers of coremat and epoxy will stiffen the area greatly. After initial cure of 12 to 24 hours, postcure the epoxy/coremat with some mild heat, no more than 120 to 130 degrees for 24 hours. The postcure is not absolutely necessary, but it will add some greater degree of stiffness than without. Good Luck!
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Old 12-19-2011
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Would the hull likely be permanently deformed if I excised all the damaged fiberglass and re-laid new fiberglass in the hole from the inside while the boat was on the hard on jackstands?

(I know a cradle would be the ideal, but this would be another substantial additional expense.)

Last edited by jameswilson29; 12-19-2011 at 09:32 AM.
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Old 12-19-2011
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Quote:
Originally Posted by jameswilson29 View Post
Surveyor surmised it was the result of improper jack stand placement and recommended inspection by professional fiberglass repairer. I understand hull indentations are often found on Pearsons from this era because of combination of relatively heavy displacement and light construction aft of the cabin bulkhead.

I doubt it was previously repaired as there is no access to the area, except outside the hull.
Your surveyor may have a good point before doing any type of "repair" work. Probably worth the cost to get input from somebody who has "been there and done that"?

Dabnis
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Old 12-19-2011
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This is a very common problem with *improperly blocked* Pearsons (especially the 26, 30, and the Flyer).

How to block a Pearson (or just about any boat with a 'swept back' keel).
1. Set a block of wood just aft and under the leading edge of the keel.
2. Look at where the trailing edge of the keel joins the hull .... draw an imaginary vertical line down to the bottom of the keel ---- the second block of wood under the keel goes IN FRONT OF this imaginary line. Any blocking under the keel aft of this imaginary line will cause hull deflection, especially in P30s, P26s, and Flyers. Any blocking under the aft end of the keel can cause the bottom aft end of the 'swept back' keel to break ... there is NO ballast in the bottom aft end of the keel, it's hollow and it cannot support much weight!
2A. "MOST" of the boat's weight should be onto the block just behind the keel's leading edge.
3. Set up 4 jackstands AT the bulkheads (there is no bulkhead on the aft port side of a P30 but set a Jackstand there anyway)
4. Add a vee poppit jackstand at the bow, another vee-poppit between the rudder and the prop ..... and set these vee poppits very TIGHT !!!!!
5. If the boat is stored with the mast up, dont relax the rigging.

What has happened is that improper blocking under the aft section (behind that imaginary line) is causing a 'moment-force' that is causing the keel to ROTATE (in the vertical plane) and is driving the aft edge of the keel INTO the hull ... and the hull is stress relieving itself through such 'deflections' (planar 'buckling').

Not to worry about what has already happened. In the entire history of when Pearson was actively in business there was never any delamination caused by improper keel blocking. The Pearson brothers at that time were the best in the business in fiberglass design. When the boat is returned to the water, such defections will pop-out over time. If the boat is accessible to a travel lift, re-set the boat to the above directions .... otherwise wait until spring .... but if you cant 'reblock' be sure to add those vee poppits and set them TIGHT, especially the one that goes between the rudder and the prop.

Remedy/Prevention - is to ALWAYS give your yard a drawing of where the blocking goes and where and how many the jackstands should be , and apply graphic indicaters along the waterline where the 'bulkheads' are located.
DO NOT 'jack out', 'lever' from behind the liner, fill or 'fair' nor 'otherwise repair' any such hull deflections, they will ultimately return to 'normal' shape when the boat is back in the water. Proper blocking of a swept back keel will prevent this in the future.
FWIW your 'dimpling' / hull deflection appears to be very minor in comparison to a very badly blocked Pearson !!!!!!!

Pearsons of this era (Gruman Industries ownership) were 'floppy hulls' .... if you are actively racing this boat then consider to add longitudinal stiffeners running parallel to and 18-20" offset/outboard from where the bilge 'turns' from the keel. Just a kerfed 1x1" covered with 'tabbing' will do ... and will greatly stiffen the hull and the boat will then be a 'little faster' especially in 'rough' water. If you elect to add such 'stiffeners', do so when the boat is free floating in the water and not set on 'jackstands'.

Last edited by RichH; 12-19-2011 at 11:58 AM.
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Old 12-19-2011
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Thanks for your responses and your reassurance.

I was wondering if I made a stupid mistake by ignoring the surveyor's advice to have a professional fiberglass repairman inspect the area. In my cynical view, this was a CYA setting me up for someone explaining why I needed an expensive repair beyond my limited abilities and comprehension.

The Pearson 28 does not have a swept back keel - the aft section is vertical. I did instruct the yard to put the jackstands where the bulkheads are. There are currently 6 stands, two each at the main and aft bulkheads and two at the bow instead of a vee. The only one missing is the jackstand between the prop and the rudder. Since the P29 has a skeg rudder instead of a spade rudder, this should probably go aft of the keel before the prop shaft under the inboard?

Last edited by jameswilson29; 10-07-2012 at 01:32 PM.
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Old 12-19-2011
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How long have you owned this boat? Have you had her in the water for a reasonable period of time?

I ask the question, because a few responders have stated that the indentation will pop out on it's own. I'm trying to understand if you've already given the hull an opportunity to relax in the water or not?
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  #19  
Old 12-19-2011
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I bought it November 6th and sailed it down from Annapolis to Potomac River. The boat sailed and motored great, no problems. I hauled it out 2 weeks ago. The hull deflection was noted on the PO's out-of-the-water survey. When I inquired about it, the PO told me it had popped out. I had a condition and valuation survey in the water, without a haul out.

I do not remember seeing the deflection initially when the boat was on the lift.

Here's a photo on the travel lift: http://www.sailnet.com/forums/member...ravellift.html

Last edited by jameswilson29; 12-19-2011 at 12:21 PM.
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Old 12-19-2011
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Quote:
Originally Posted by jameswilson29 View Post
Thanks for your responses and your reassurance.

I was wondering if I made a stupid mistake by ignoring the surveyor's advice to have a professional fiberglass repairman inspect the area. In my cynical view, this was a CYA setting me up for someone explaining why I needed an expensive repair beyond my limited abilities and comprehension.

The Pearson 29 does not have a swept back keel - the aft section is vertical. I did instruct the yard to put the jackstands where the bulkheads are. There are currently 6 stands, two each at the main and aft bulkheads and two at the bow instead of a vee. The only one missing is the jackstand between the prop and the rudder. Since the P29 has a skeg rudder instead of a spade rudder, this should probably go aft of the keel before the prop shaft?
There is too much weight being supported by the aft section of the keel ... swept back or not doesnt make any difference on a Pearson and in 'reaction' to this 'unbalanced stress' the (floppy) hull is 'buckling'. You really have to get 'most' of the weight/mass of a Pearson supported by the 'front' section of the keel. On most Pearsons the aft section of their keels are usually 'deeper' than the front sections ... a yard will set the weight onto the 'front block' then rotate the boat onto the 'aft' block leaving the aft block to support 'most' of the load .... on a Pearson if you dont want 'dimples' the boats weight has to be 'mostly' on the 'front block'.

.... plus you do need the 'extra' support via a vee-poppit somewhere between the prop and the rudder and as 'far aft' as you can locate the vee poppit ... this vee poppit will 'help support' and take some load OFF of the block that is at the aft section of the keel.

Next time the boat is blocked set the 'front block' and a support block somewhere near of just aft of the 'middle' of the keel .... and you will get NO hull deflection. I cant make it any 'simpler' than: Keep the load (mostly) off the 'aft section' of the keel ... and you wont get hull deflection on a Pearson.

As stated before, rarely will a Pearson hull 'delaminate' ... the Pearson brothers were 'that technically knowledgeable'.
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Last edited by RichH; 12-19-2011 at 05:27 PM.
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