# Repair hull indentation/flat spot?



## jameswilson29 (Aug 15, 2009)

There is a hull indentation/flat spot in the starboard bilge area of my P28, photo attached: SailNet Community - jameswilson29's Album: Winter repairs: hull indentation - Picture

The inside of the hull is currently inaccessible due to the hull liner. I could gain access by cutting ports in the starboard cabin berth locker.

Is this worth repairing?

I am considering trying to pop out the indentation and adding additional fiberglass laminate and stringers to strengthen the area.


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## raisin56 (Jul 26, 2008)

The real question is how did it get there?
Not knowing the history of the vessel I would suspect a repair by a PO that wasn't fared properly. I would strip the paint off down to the gel/glass and see what I find. A repair could be hard to detect if they were good a gel work, but if they were that good they should know how to fare the hull. Look for any stress fractures around the flattened area if it is not a repaired area. Glass doesn't "pop" like sheet metal on a car would, other means of repairing damage would be needed.
If you don't find any stress fractures and aren't planning on making it a fast racer the put on a new bottom coat and enjoy the sail.

Dan


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## Traveling Light (Dec 2, 2002)

It might be damaged from hitting an object but I would not rule out improper keel support if the PO used jack stands. Nonetheless, I agree with Dan, if no serious damage, just verify, and don't worry about it.


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## jameswilson29 (Aug 15, 2009)

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.


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## Faster (Sep 13, 2005)

As you say, Pearsons are known for being what some call 'soft shell' boats and can suffer from this kind of indentation, usually from improperly placed pads/stands. Usually, though, they'll tend to pop back on their own once the force is removed.

The fact that this has not occurred makes me wonder if the laminate is fractured slightly in that area... that's kind of tough to be sure about, esp as the area is inaccessible from inside.. can you at least 'see' if the inner surface is intact? (not that that is any guarantee of the integrity of the area..) Any difference in the 'sounding' in that area and adjacent 'normal' appearing parts of the hull?


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## jameswilson29 (Aug 15, 2009)

*Sounds different to amateur...*

Yes, I was rapping on it with the handle of the scraper I was using and it sounded different from the surrounding area, although it is difficult to tell because aft of it is a cabin bulkhead, below is the reinforced bilge sump area, forward is the main bulkhead...

I would have to cut into the liner to access this area for an inspection. I am not sure I would recognize the difference between damaged laminate and undamaged laminate.

Could I pop the area out using a jack between the hull and the liner or tapered wood pieces hammered into place temporarily?

Would there be any harm in adding laminate and stringers to reinforce this area?

(I did not intend for this to be a "project boat", although it seems to be becoming one; the boat is inexpensive enough I am hesitant to pay for professional fiberglass repairs.)


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## SloopJonB (Jun 6, 2011)

jameswilson29 said:


> Yes, I was rapping on it with the handle of the scraper I was using and it sounded different from the surrounding area, although it is difficult to tell because aft of it is a cabin bulkhead, below is the reinforced bilge sump area, forward is the main bulkhead...
> 
> I would have to cut into the liner to access this area for an inspection. I am not sure I would recognize the difference between damaged laminate and undamaged laminate.
> 
> ...


* ALL boats are "project" boats. It's just a matter of how much of a project they are.*

P.S. If you do decide to cut into the liner, plan it carefully so you can make it look good later - like a planned and designed access port. Nothing screams "uncaring owner" quite like crude holes hacked in a moulded liner.


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## Tim R. (Mar 23, 2003)

That vintage Pearson 28 does not suffer from any lightly built areas in the hull. In fact this is the first I have ever heard anyone say that this Model and vintage Pearson was anything less than well built. What are these claims based on?

This is likely not a deflection from an improperly placed boat stand. This is a poor repair. Once you strip it down to the glass you will be able to see what was done.

If it is a repair, then there is probably no gel coat where they did the repair. No reason to cover an epoxy based repair with gel coat just to be covered by AF paint. Gelcoat is cosmetic. Once you remove the paint, it should be obvious. Maybe it is a poor repair because they did not do any work from the inside. Where on the inside of the boat does this repair line up?


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## Faster (Sep 13, 2005)

Prying against the liner would probably be a bad idea.. it may crack itself.

Jon's got a good point - cut into the liner in a way that you can install an inspection port so it looks OK afterward. If the laminate is damaged, once you get a peek you should see some surface splintering.. but the difficulty is that even if you don't it's no guarantee that there isn't internal fracturing.

Adding stiffeners or reinforcement may require (at least temporary) removal of most of that section of liner...


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## jameswilson29 (Aug 15, 2009)

*Pearson hull deflections*

I am a big Pearson fan - this is my second Pearson. Nevertheless, I realize that every boat has its weak points, including Pearsons, which can suffer from hull deflections when improperly blocked. I do not blame Bill Shaw or Pearson for not anticipating boneheads working in marinas. If you search the internet for hull deflections/flat spots/indentations, Pearsons frequently come up as the subject vessel, usually one of the more popular models, such as the P30. Here is a previous instructive sailnet thread on the subject: http://www.sailnet.com/forums/p30/67354-pearson-30-1973-a.html#post632736

I have seen a number of others on different websites.

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: http://www.sailnet.com/forums/members/jameswilson29-albums-winter-repairs-hull-indentation.html .

I believe the thru-hull in the photos is the galley sink drain (icebox drains into the bilge).


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## SloopJonB (Jun 6, 2011)

jameswilson29 said:


> 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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## jameswilson29 (Aug 15, 2009)

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.)


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## pmcguire (Nov 5, 2007)

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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## jameswilson29 (Aug 15, 2009)

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.)


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## dabnis (Jul 29, 2007)

jameswilson29 said:


> 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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## RichH (Jul 10, 2000)

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'.


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## jameswilson29 (Aug 15, 2009)

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?


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## Ajax_MD (Nov 24, 2009)

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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## jameswilson29 (Aug 15, 2009)

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/members/jameswilson29-albums-s-v-thoe-picture512-travellift.html


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## RichH (Jul 10, 2000)

jameswilson29 said:


> 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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## jameswilson29 (Aug 15, 2009)

Thanks, again. This is the listserv at its best - you saved me from spending considerable time and money and gave me some peace of mind to enjoy the holidays, instead of plotting how to cut the hull and figuring how much resin I should buy.


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