What's the best wood to use for stringers replacement.

[newtons law]

Recently acquired 1984 Galaxy conquest has bad flooring. While cutting it out,I realized that the two stringers on either side of the ski storage are rotted. Cutting the top cap to remove the rotted wood. Noted the outer fiberglass shell that incases the stringers will only allow three quarter inch thick board. Should I cut the side walls,so I cauld use two by boards,or stick with three quarter that are sealed in resin? Thanks

 

[Pmt133]

3/4 exterior plywood is probably what it was built with. (I've seen from friends that OSB was used in cheap boats at the factory) So yes, you'd have to cut that shell, adhere the board or float it then glass up around and over it back to the hull.... I used a local lumber yard, told them what I was doing and they delivered excellent quality wood to my location for the same price as the cheap stuff at HD and the like and it was already dried! So look around. Chances are you're going to have to go through everything on the hull if the stringers are gone...

 

[newtons law]

3/4 exterior plywood is probably what it was built with. (I've seen from friends that OSB was used in cheap boats at the factory) So yes, you'd have to cut that shell, adhere the board or float it then glass up around and over it back to the hull.... I used a local lumber yard, told them what I was doing and they delivered excellent quality wood to my location for the same price as the cheap stuff at HD and the like and it was already dried! So look around. Chances are you're going to have to go through everything on the hull if the stringers are gone...

Thanks, was afraid screws would split the ply. The wood was solid from front to middle. Then it was mush. Thought maybe dry oak would last longer if floated and glassed. But the cheapest lasting ideas is what I'm searching for. Found shift cable bellow was bad,and suspect it played a part in this damage.will be replacing all bellows before it See's water again.ive replaced floors in two boats. All was good. But they didn't need new stringer's. Space inside the glass covering appears to be three quarter inch thick,ans a little over five inches tall. Hoping to slide new wood (pre sealed) ,and fill space with resin,then glass cloth.

 

[tpenfield]

Post some pictures when you can, as it helps with responses.

The boats that are still made of wood structure (bones) use what is known as 'KDAT' plywood. 2 product names of KDAT are 'Perma Panel' and 'Greenwood XL'.

If you want to do old school, you could use exterior grade plywood, as it is more readily available at a retail level.

 

[Grub54891]

I used marine grade plywood. Could have used construction grade but I didn't want any hidden voids.

 

[todhunter]

Sliding new wood in the fiberglass carcass of the original stringer isn't a good idea. Getting the sides of the new wood to bond with the inside of the old glass will be difficult. Without the glass and wood being tied together (unless the glass is VERY thick), your new wood won't properly carry the loads the hull is going to be exposed to.

I recommend using ACX plywood, exterior grade. Cut the old stringers out (fiberglass sides and all), bed in new stringers, then glass them into the hull. Regarding your concern of splitting the plywood with screws, I screwed solid wood (sapele) cleats into the sides of my new stringers, then screwed the floor down into the cleats. Sapele is a rot-resistant hard wood that can take a screw without splitting (I still recommend you pre-drill the holes).

 

[Scott Danforth]

go here. https://forums.iboats.com/threads/how-tos-and-other-great-information.283508/

read the threads in links 14, 15, 18, 2, 3, 4a, and 4b do not skip. watch every video, look at every picture.

 

[newtons law]

Sliding new wood in the fiberglass carcass of the original stringer isn't a good idea. Getting the sides of the new wood to bond with the inside of the old glass will be difficult. Without the glass and wood being tied together (unless the glass is VERY thick), your new wood won't properly carry the loads the hull is going to be exposed to.

I recommend using ACX plywood, exterior grade. Cut the old stringers out (fiberglass sides and all), bed in new stringers, then glass them into the hull. Regarding your concern of splitting the plywood with screws, I screwed solid wood (sapele) cleats into the sides of my new stringers, then screwed the floor down into the cleats. Sapele is a rot-resistant hard wood that can take a screw without splitting (I still recommend you pre-drill the holes).

Thanks, good information!

 

[newtons law]

Post some pictures when you can, as it helps with responses.

The boats that are still made of wood structure (bones) use what is known as 'KDAT' plywood. 2 product names of KDAT are 'Perma Panel' and 'Greenwood XL'.

If you want to do old school, you could use exterior grade plywood, as it is more readily available at a retail level.

 

[cyclops222]

What is with all those loafs of bread in the flooring area ?

 

[Lou C]

Lol
Looks like un pain francais!

 

[cyclops222]

If I ever have to screw into the edge grain of plywood ? I use a pilot drill about the same diameter of the solid body of the screw. I use longer bodied screws then.