1. The forums software has been upgraded and we are still sorting out its quirks.
    Please relay any problems you encounter. Thanks for your patience!
    Dismiss Notice

Plywood for rough use boat

Discussion in 'Serious Boat Building Questions' started by BEARS BUDDY, Aug 13, 2016.


    BEARS BUDDY Well-Known Member

    Anyone have any experience with Southern Yellow Pine (SYP) for a pirogue or similar craft built with the stitch and glue method? I have done several with luan and/or fir plywood, but none with SYP.
  2. jdupre'

    jdupre' Well-Known Member

    Bear, never used it in stitch and glue method, but my last pirogue was made with it and I'm sold on the stuff. Much better finish and almost no defects in the outer plies. I've had an un-painted small model outside in the elements for almost 3 years and no rot, very little warpage and one 6" x 1/2" delamination around a split. It doesn't check near as much as fir ply.

  3. mike

    mike Well-Known Member


    Did you use regular, or treated?

  4. jdupre'

    jdupre' Well-Known Member

    Regular sanded plywood. Almost 3 years in South Louisiana elements with comparatively little damage. I'll never use fir marine ply again if I can help it.

    BEARS BUDDY Well-Known Member

    Thanks for your answer. I was thinking of using the SYP plywood as it is plugged on all layers for use as underlayment. I have always covered the boats with a layer of 4 or 6 oz. glass and epoxy. No issues with either fir or luan, even when a strap broke at 70 mph on the highway. Slowed to 55 before the boat flew off the trailer. Damage was limited to the starboard bow on a mouseboat. Only needed a patch about 6x6 inches and some glass repair over that to be good as new. Also I only tie the boats down now, no ratchet straps.
  6. Wannabe

    Wannabe Well-Known Member

    Be very careful of underlayment. It is not supposed to but it can have voids now and again. Check each sheet carefully.

    BEARS BUDDY Well-Known Member

    Always do a check for voids. We received some marine mahogany ply at the marina where I worked in the 70's that had voids in the inner plies.

    BEARS BUDDY Well-Known Member

    Well the boat build is off the table for now. I have gone over to the dark side of the force and purchased an O'Day DaySailer in fiberglass. 16' 9" long sloop rigged,will float in seven inches of water. Should be great for fishing and coastal cruising.
  9. Kayak Jack

    Kayak Jack Well-Known Member

    Good on ya, Gerry! A new endeavor!

    I lusted after an O'Day. But, being in the Air Fotce at the time, I couldn't depend on remaining around water. While in Okinawa, I did sail little stuff a little bit, but nothing like I dreamed about.
  10. texastom

    texastom Well-Known Member

    How to check for voids?

    I see that advice often and understand why it's important, but not sure how to accomplish it. Unless the void is on the outside and presumably repaired with a "football", how would you know there's a void without cutting into it?

    BEARS BUDDY Well-Known Member

    I just decided to get on the water with something I could overnight aboard if need be. Mostly going to be a fishing platform, most sailing will be to and from sites. This bay was at one time the largest fresh water fishery in the world.

    BEARS BUDDY Well-Known Member

    Re: How to check for voids?

    Most will be difficult to find. The best way I have found is to flex the sheet slightly and sight and feel for flat spots. If it looks flat tap lightly with a hammer or mallet to see if it is solid inside.
    The plugs are fine except for the face of an appearance sheet. Voids can be repaired from the back side by making a small hole or holes in the outer layer and filling with epoxy. That is best done after the sheet is in place if it is to be sharply curved. Pieces like a pirogue side or bottom sheet can be filled before or after because they are not sharply curved like some kayak panels.
  13. Wannabe

    Wannabe Well-Known Member

    For thinner stuff you will be making a boat out of hold it up with a Bright light or the sun on the other side of the panel and you will be able to see the voids if any.
  14. Kayak Jack

    Kayak Jack Well-Known Member

    I operate at the other end of the sectrum. While some pride them selves on how cheap (as opposed to just inexpensive) a material they can get away with to build a boat, I use the most expensive. Mahogony BS1088 is the only material I've ever used.

    Yes, this is likely to sprout a lot of channel-clogging talk about "how little I spent, and how long it's lasted." Some admire cheap; others don't.
  15. oldsparkey

    oldsparkey Well-Known Member

    :lol: :lol: :lol: Ya don't have to buy a Rolls Royce when a Volkswagen will do the same thing. A true artisan can turn a Volkswagen into a Rolls with knowledge and skill. As far as either vehicle lasting that usually is determined by the care , consideration , respect , lack of deliberate abuse along with the proper maintenance of it.
    PS. Nothing lasts forever , eventually everything wears ( fades ) away. ( Even Us ) :roll:

Share This Page