stringers repair or replace?

I have a 36 ft motorsailer and the stringers which were made from mahoganey are mostly rotted out, I really don't want to tear out the entire boat, is there any way to repair, the figerglass that covered the wood is about 1/4 thick and none are cracked, the hull is very thick and I saw no signs of stress, my question is a product like Seacast is it better than epoxy , it is a little cheaper, and there are some areas I would have to tear the floor up to cut the tops off the stringers and remove the old rotten wood, anyone have any ideas

 

seacast will not help. Seacast is used in transoms where you need compression strength - stringers are a different animal. I doubt the stringers would be any stronger than if you left the old wood in there.

If the stringers are getting their stiffness from the glass and the wood was more or less a form, then you might be OK.

I do not believe there is a good option for a quick fix. you either leave it the way it is, or rebuild the stringers. Sorry

 

I agree with JR... if you have sufficient glass thickness, and your panel thickenss is good enough, then the wood in the stringers is basically going along for the ride. Otherwise, as JR said, you either have to do them all or not. If you are worried only about areas where compression strength is an issue (in the case of motor mounts, etc) then you could patch in some spots for that purpose and leave the rest alone.

good luck

 

what to patch with?

Should I used poly resin, with milled fibers or and epxoy for the compression areas, such as the mast mount, and the enigine mounts?

 

Depending on the stringer material you choose to use, you shouldn't have to do any of that. Using a good material (decent density foam, or plywood, etc) if you have sufficient laminate thickness in that area and you use a decent size backing plate, then all you have to do is put a couple of dabs of 3M 5200 on the motor mount and backing plate mount to keep the plates from moving back and forth which will elongate your holes. Also don't overtorque your stringer mount bolts, use a decent spec and a torque wrench, along with nyloc nuts and you'll be fine. We run the offshores this way and have zero problems with them.

good luck

 

stringers

Is there any kind of injectable foam I can inject into the stringers and glass over them?

 

two part urethane foam and 3 layers of 1810 glass over them should work.

 

Hi I work for Seacast LLC My name is Bobbi You can Use Seacast on stringers just like you said. You cut the tops off stringers and remove all wood a least 90%. Make sure you clean areas of stringers so there is no oil or debrie mix and pour Seacast and you can cap off with 4" or 6" fiberglass tape while Seacast is still wet. The Seacast will wet out the fiberglass. This will form your skin on top of stringer. You can add another layer after it cures. We have Seacast for Transoms, Stringers and Floors and Decks. We have a new website with a forum for Seacast questions answered daily. Or you can call me personally with any questions at 877-716-4820. www.transomrepair.com

Also I wanted to add Seacast is formulated so it absorbs shock and will not crack. There is no shrinking or expansion during cure. It is water resitant, floats and will never rot and it is three times stronger than marine plywood.

From Your Friend At Seacast LLC
Bobbi

 

Bobbi, if I cut the tops off all the stringers, then I have fo field strip the boat, I want something I can inject or pour into holes, where I don't have to cut the complete top off and clean it, hell if I had to cut the tops off and clean it down ,I would replace the wood and reglass, the problem is I don't want to dismantill the boat, as I said the hull is thick and none of the stringers are cracked, the skin of the stringer is 1/4 plus, I know the wood is rotten because I drilled holes in the top off the stringers

 

Seacast could be poured thougth holes but most of the rotten wood would have to be removed. So you would have to cut more than one or two holes to remove rotten wood. If you want you could email me some picture so we could get a better look at what your working with.

info@transomrepair.com

 

I would like to see som pictures as well. Even though you aren't seeing any cracks now, remember that you have drill holes and done some cutting. Chances are (and I don't know where your stringers are located) that filling them with something could make the boat heavier or making the hull kore rigid. The designer had a reason for the wood and possibly probable it should be replaced with something similiar. If you filled them with epoxy with the possibility of adding rgidness to the hull it can affect sailing and handling characteristics that you have already became accustomed to. The wood is already rotten so until you cutt them out you may not know how or why they are rotted. Its possible that the wood and glass cracked somewhere allowing water to be able to rot it. Just a thought though. I understand keeping down cost, safety could be an issue as well.