E39 Cored Hull Repair

stillwater

Member II
I am repairing a fracture/crack in the aft section of the hull, starboard side, aft of the trailing edge of the keel about halfway to the waterline. The area that was ground out is about 18" top to bottom and 3" wide. The core was wet here and the inside layer of glass was fractured as well. Surveyor thought maybe a ground heaving jackstand might have done this!

My question is, has anyone done a similar repair? Was "Maverick" a cored boat?

This boat has been stored out of water, covered for the last 3 years so water intrusion has not been a problem. The boat weighed 20,000 lbs in the slings with all the gear aboard.

I am just getting started with this boat and it is the one with the single spreader mast. It turns out that it is a custom Hood spar that was installed at the factory. There is no obvious hull number and there is conflicting information on age. This was a one owner boat. The Document says 1972, the broker said 1973 and there is a plaque on the boat for the 1971 Marblehead to Halifax race/cruise.?

Dal Farias
E39 Stillwater
Bellingham, WA
 

Loren Beach

O34 - Portland, OR
Senior Moderator
Blogs Author
As to that plaque, it is not unusual for an owner to transfer a participation plaque from boat to boat... But then I would wonder why he left it behind when he sold this boat?
Interesting about the (rare?) cored hull. I hope that the damage repair goes well.

As to HIN, it seems like a '71 boat should have had one applied by the factory, AFAIK. Trouble is, after so many decades, hulls get repainted or repaired and some yards do not re-apply the HIN to the top coat. I know of one local repair business that has their own "reverse print" Dymo labeler and routinely remolds the HIN into the upper transom when they do a hull rebuild/refurbish.

Best of luck on your project.
Loren

ps: if the owner is still alive, best just to call him up and ask him these questions........
 
Last edited:

Guy Stevens

Moderator
Moderator
39s etc

There were few of the 39's that were produced with cored hulls. The cored hulls are more stable, and the insulation properties are a good thing to have. The downside you see.

The way to fix it is to put it back the way it should be. Get end grain balsa of the correct thickness, cut it to fit in the hole. Epoxy is the the material of choice for repairs due to the better post cure adhesion properties of epoxy over polyester. The balsa core is actually small blocks connected with a fine light mesh. The easiest way to repair is to make sure that you take out and replace full blocks.

Make sure that your balsa mat fits into the area to be repaired as perfectly as possible. Mix epoxy with a thickener, coidial Silica for this would be my choice, apply the paste to the inner skin of the boat use more than you think you need liberal application here is best, it will eliminate voids to be filled later. Place the balsa mat in the area. Mix up more epoxy and silica and generously coat the balsa top side. Make sure that any voids in the balsa between blocks are filled with epoxy and silica filler at this point also. Glass over the top with a correct laminate schedule and correct bevel to the hull.

I would at this point vacuum bag the repaired area since it is an overhead repair and will have bad tendencies to sag. Follow standard vacuum bag procedures in the west system book on the subject and you should be golden. Fair as needed.


x-Maverick is not cored.

Below the sole connecting the forward structural bulkheads on an e-39 is a 3/8 thick steel weldment that serves to connect the two bulkheads together and to limit torsional loads on the hull. There is another much like it that connects the aft main bulkheads, (The ones in front of the galley and the quarterberth). These are important weldments. They avoid making the bulkheads into a torsional stress riser. Make sure that yours are there, and that they are in good shape.

Hull Number should be located on the starboard upper corner of the transom. The number starts with ERY. Sometimes even if you cannot see it, it may be there painted over. The solution to this is to do a rubbing with a crayon onto a piece of paper over the area.
Guy
:)
 
Last edited:

HughHarv

Hugh
Inside Out Repair

I'd look inside and try to repair from inside out, if possible. Much easier than fairing a big hole on the outside of hull with compound curves.
 

Walt Lawrence

Member I
Hull # and construction date....Location?

:egrin: On my 39 I found the hull # and 2 digit date embossed, or stamped if you like, in the ring of the metal cover over the emergency tiller socket on the cockpit deck...

28 71

Hope this helps....HINs weren't required before 1972 if I remember right...

WEL
 

stillwater

Member II
Hull Number on Emergency Tiller Ring

There are numbers on the ring on my boat as well. But it has 39 36. I assume it means a 39' hull #36. Other literature says this is a 1972 boat so that makes some sense.

I am repairing the crack from the outside because it is behind the ice box. I have laid up a layer of matte to firm up the inside. I will then put in the balsa core and probably use layers of 18oz biaxil for the outside layup.

Dal
E39 "Stillwater"
 

HughHarv

Hugh
Hull Repair

I had a crack in the same area behind the icebox. Mine was caused from the cradle pad (previous owner let the keel blocks rot and the boat settled onto pads. I chased rotted core till I had a 2' x 2' area open. Lots of work to fair. When you get to the fairing part I'd recommend using a batten to make a ridge or two of fairing material accross the area, then filling the rest to match.
 
Top