Wood questions

[Toad]

I live in rural Arizona and I am planing to build a small wooden skiff. I have some plywood lined up but I have questions about lumber. The boat requires I build a simple frame and cover it with plywood. The wood available to me are some form of pine and maple along with poplar and red oak. I realize these are not standard species for boat building but these are what I have to choose from. This is not an ocean going boat and it will spend most of it's life on a trailer. I got an email from a guy who told me that if coated with a clear epoxy wood sealer the rot resistance for the red oak would go up dramatically. All wood on my boat could be covered with epoxy of some kind so I wondered about the other types of wood. I could also cover the outside with vinyl ester resin and light cloth and give the inside a good coat of wood preservative then primer and paint. I would like some thoughts on the subject. Pine, poplar, maple or red oak???

 

[lobsta1]

Epoxy is a much better adhesive than vinyl ester & maybe has better water resistance. Epoxy does not have any UV resistance. Without a UV barrier coat on top, it will break down in the sunlight. Poplar also does not have decent rot resistance. In your dry climate it probably does not matter. Just make sure when it is sitting on the trailer that water does not collect & stay inside.

Neither vinyl nor polyester will properly adhere to epoxy. Epoxy will adhere to the esters. Before putting a second coat of anything on epoxy, wash with soapy water with a green scrub pad to get rid of the amine blush that rises to the surface. Anything you cover with either an ester or epoxy will be sealed from any wood preservative soaking in.

I know of many guys that have built stitch-n-glue dories & just painted everything with latex house paint. Since the boats were not staying in the water, that was deemed sufficient protection.

Good luck & have fun.
Al

 

[Toad]

Yep. I have made stitch and glue boats before but I have always had fir to work with. This will not be a stitch and glue boat. I am trying to get away from that type of boat for awhile. Give this type a try. I brought up the vinyl ester resin option for just sheathing the outside as it has a higher heat and UV resistance than most epoxies. I will be using a glue, but all wood will also be fastened with stainless screws. My question is about the different lumber available to me. I had hoped to use some of the dimentional 1x lumber sold locally. I am of half a mind to purchase a table saw (which I should have done some time ago) and just rip enough 16' construction grade fir 2x6's until I have enough for my inner chines, rub rails and a large portion of the framework. Done that before and it worked well. The wider boards I need will have to be one of the wood species I have named above. I guess I could get away with the ponderosa pine and coat the entire inside with Cuprinol #10 and then paint the dang thing..

 

[lobsta1]

When is your next trip to Tucson? Is either fir or redwood decking available to you? Since you don't have to worry about moisture out there, I would probably choose the poplar. Least amount of knots & most dimensionally stable & works easily.
Al

 

[Toad]

Ya know, I wrote a fella back east who builds small boats using poplar. He thought highly of it. My brother used it for a bow stem in his Row Me 12 foot skiff. I have found over the years that wood that has been sealed seems to last a good long time. I talked with a gentleman whose company makes a clear epoxy wood sealer. Told me that if the cut ends and exposed wood is treated with this product it would dramatically lengthen the life of red oak in an outdoor environment. Your correct. With the exception of our summer monsoons we are pretty dry around here. If it were not for the decay factor red oak has all the qualities I am looking for in a framing material for a small boat. It does not take a lot of lumber. Worth the expense of the epoxy to seal it up good. I am learning something new every day.

 

[Toad]

http://www.rotdoctor.com/test/plywood/plywood.html

I hope it opens. It is a link about using clear penetrating epoxy sealer on plywood. I lived in the Bellingham, WA for awhile and over by the Olympics and I remember what Washington rains are like. Soooooo glad I moved to the desert. The fella said it would work on Red Oak..

 

[TraditionalTool]

http://www.rotdoctor.com/test/plywood/plywood.html

I hope it opens. It is a link about using clear penetrating epoxy sealer on plywood. I lived in the Bellingham, WA for awhile and over by the Olympics and I remember what Washington rains are like. Soooooo glad I moved to the desert. The fella said it would work on Red Oak..

I would expect it to work better with oak than maple, only because oak is an open grain and maple is not.

That said, I love to work maple, it does everything so nicely, it shaves, cuts, mills, carves, etc...it's great wood, and fairly forgiving...

Both oak and maple are strong, if one was better in regards to steaming I would think oak, but not sure. I'm not sure if you will be steaming any of it, but know that boat builders do that from time to time.

Regards,
TT

 

[lobsta1]

I've read numerous times over the years that epoxy does not adhere as well to white oak as to most other woods. I think it is due to the tannin acid content. Don't know about red oak as it is not generally used. If you take a small block of red oak & put the end into water, you can blow through the other end & start making bubbles. The red oak is almost like a bunch of small straws bound together. IF you could fully fill those small tubes, then the rot problem probably goes away. You can fill the ends, but how do you get to the middle of a 4' long piece. Six months after you finish, you drop your anchor inside the boat & crush the wood fibers in a small area. You have now opened up new ends to those unfilled tubes. In your climate it probably won't really matter. Just be aware of the potential.

Please do not believe all the Dr Rot hype. They make a good product as do the other companies. To achieve the penetration, they have a VERY high percentage of solvent. When the solvent evaporates, there is only a thin coat of epoxy left. So you have to do multiple coats to achieve a decent film thickness.
Al

This site has a VERY EXTENSIVE knowledge base as well as links to every where else.
http://www.epoxyproducts.com/marine.html

Another good site:
http://www.westsystem.com/ss/

Less expensive than West, System Three or Dr Rot:
http://www.raka.com/