Plywood Composite Pirogue

[icemanxxxv]

I've had the plans for Uncle John's Pirogue. I've been contemplating building a different boat for a while but have come back to the Pirogue. I've done some research on the Stitch and Glue Technique used on other boats and I've decided that it's probably the way I will construct my Pirogue. I intend on completely glassing the inside and out side of the Pirogue with 3.25oz. glass. Before the frames are installed . I will be using temporary spreaders across the top in the places where the frame would be to maintain the shape so I can facilitate instillation of the framed after the glass has cured. I'm still sourcing wood, RAKA Inc. will be my source for composite material. Build table is first than the boat build will begin.
Here are my first two questions.

Will anyone chime in here on this technique glassing before frames?

Will the boat be stiff enough to handle (move around flip over) before the rub rail instillation?

 

[oldsparkey]

Will anyone chime in here on this technique glassing before frames?

Will the boat be stiff enough to handle (move around flip over) before the rub rail instillation?

Some of the guys have glassed the panels of there boats before assembling them , I haven't so I can't offer a lot of advice on that process.

When the side boards are in place and attached at the bow and stern it is normal practice to install the ribs before the bottom is attached. Doing it that way there needs to be one rail attached to the top of the sides or the sides will buckle breaking one or more of the ribs. Usually it is the outer rail that is attached at that time.

With the wood glassed it will offer more strength to the boat so by doing it your way it would be a guess on my part. I think that without the ribs or a rail on the sides there still would be some flexing since there is nothing there to help maintain the shape , to what degree is only a guess.

Chuck...........

 

[Kayak Jack]

Asking a question here. Would wooden ribs attach more solidly directly to the wood - or to a layer of glass that is attached to the wood? I've not built a pirogue, but feel that I would rather bond wood directly to wood than to something else that is in between.

I see no advantage to glassing before installation of ribs, and can think of a couple possible disadvantages. Glass handles easier (for me, anyway) in smaller chunks. So, glassing a boat section by section would seem considerably easier than trying to glass an entire span at one time. Also, glass will stiffen the panels, and could make both fitting and installation of ribs and any other framing member more difficult. Working with panels that are more flexible may better facilitate that operation?

I'm offering these as conversational questions, not hard rock facts.

 

[oldsparkey]

Attaching the side panels to the bow or stern pieces is not to hard to do , it is that last end of the one panel that needs to be attached. It can become a contest between the person and the boat at that stage.
It seams that as the panels are attached and the boat starts to take shape is when the fun starts or progresses to learning some new words , usually the 4 letter kind. 1st one , a breeze , 2nd one , not that bad , the 3rd one , I did it hurrah for me, the 4th one , where can I find a couple of weight lifters to hold this %^&$@# in place while I attach it.

 

[icemanxxxv]

Thanks for the input fellas. It does make sense to install the ribs first. Now for a wood question.

My local BBS (Big Box Store) Has Luann but it is not exterior grade glue. I'm leery of using this for the fact if I scratch the epoxy and introduce water I see big problems down the road. I would like a Nice looking natural finish or stained finish boat, and the exterior grade BC plywood at the BBS is ugly.
Wood suggestions for a pretty boat?

 

[Kayak Jack]

You're going to receive lots of input here. Best quality - and safest to use - bet is BS1088 mahogany. Others use other wood, and seem to get by.

 

[icemanxxxv]

best bet is BS1088 mahogany.

I can't get that here in Kansas City, trust me if I could I would! I thought I had a line on Meranti exterior glue but it's no longer available :x

 

[oldsparkey]

I have used the expensive wood and the cheep wood , so far all the boats made from them are still in use and floating. I believe it is or boils down to what do you want to spend on the wood.

For a 1st boat I would suggest the run of the mill Luann since it does not cost a lot and if you make a mistake in the cutting of the panels or even the construction of the boat , to replace the wood is a lot easier on the wallet.

Luann will run in the $10.00 to $15.00 a 4 x8 sheet while the good stuff ( according to Jack ) will be in the neighborhood or $60.00 to $85.00 a sheet. Might be more with postage if you have to order it.

I like the Luann for mine. A place I found over here specializes in the wood panels and they let me pick threw them but those are 1/8 inch sheets when I am making a light weight boat. Home Depot does the same for me when I am looking for wood in the 1/4 inch ones and building a normal weight boat.

I epoxy saturate them before glassing when the boat is together. Epoxy saturation is just that , saturating the wood with epoxy to protect it. The epoxy soaks into the wood adding protection and strength to the wood. I have been told that the epoxy when saturating the wood can increase the strength up to 4 times the normal strength of it. All I can say is a regular piece of wood is easy to break , epoxy saturated it is a bear to break.
Then when it is going to be glassed there is more epoxy with the glass to help protect the wood and have a natural finish.

The 1st boat is normally a learning curve for the builder and some mistakes will be made , not bad ones just normal ones. Then when it is done and a person can think about what they did and to correct it on another build if they want to , that is the time to move up or stay with the same wood. One boat to use while making changes for the other one.

I have a Uncle John Pirogue made with 1/8th inch Luann that gets a lot of use and is almost 10 years old , it is just as good today as when it was made. I think the two sheets of wood back then was $8.00 a sheet the 1/4 inch was $10.00. :wink:

It all boils down to what do you want to spend and what type of wood on this one , after all it is your boat.

 

[Kayak Jack]

Iceman, build with whatever good wood you choose. For this - and for anything you want to buy locally - try www.local.com It is a "Search for local businesses, products and services near you". Wood, cheese, cars, rope, etc. etc.

 

[Jimmy W]

Have you tried Schutte lumber company? According to http://www.glen-l.com/, they sell marine plywood in Kansas City. I would at least use a plywood with exterior glue.

 

[seedtick]

we normally build around two or three jigs. The jigs hold the sides steady as you bring the ends together and keep the shape of the boat as you insert the ribs. Just be sure that you don't place the jigs in a spot where the ribs go. With the stem pieces and ribs in place, remove the jgs and install the bottom

here you can see a jig and the ribs, just prior to removing the jig

 

[icemanxxxv]

Have you tried Schutte lumber company? According to http://www.glen-l.com/, they sell marine plywood in Kansas City. I would at least use a plywood with exterior glue.

No 1/4 or 3/8th inch I've contacted them
A local lumber yard where I live has 1/4" Exterior grade AC plywood.It will be my choice.

 

[icemanxxxv]

I have a Uncle John Pirogue made with 1/8th inch Luann that gets a lot of use and is almost 10 years old , it is just as good today as when it was made. I think the two sheets of wood back then was $8.00 a sheet the 1/4 inch was $10.00. :wink:

It all boils down to what do you want to spend and what type of wood on this one , after all it is your boat.

Is 3.25 ounce glass cloth sufficient for 1/8" luann?

 

[oldsparkey]

I have a Uncle John Pirogue made with 1/8th inch Luann that gets a lot of use and is almost 10 years old , it is just as good today as when it was made. I think the two sheets of wood back then was $8.00 a sheet the 1/4 inch was $10.00. :wink:

It all boils down to what do you want to spend and what type of wood on this one , after all it is your boat.

Is 3.25 ounce glass cloth sufficient for 1/8" luann?

That is what I use on my boats , 3.25 tight woven glass. Some of the guys say it is hard to work with but so far I have never had a problem with it and I use the full sheet on the outside and pieces on the inside between the ribs of the boat. I do not glass in the ribs , just epoxy saturate them really good.

If you are thinking of 1/8th inch wood I would suggest 1/4 inch for the 1st boat and then the 1/8th inch since it is harder to work with. Also on the 1/8th inch I run three stringers down the length of the boat on the inside , one down the middle and one on each side of it down the middle of the open areas so the bottom is divided into thirds.
The stringer I use is 1 1/2 by 1/4 inch pine lattice strips , they are just enough to stop the bottom from oil canning on you.

Chuck......

 

[icemanxxxv]

thanks for the replys Chuck much appreciated! Will be Locating and purchasing the wood this weekend. Plus the order from RAKA.

 

[icemanxxxv]

OBTW Whats the Second best wood besides Cyprus for the stems?

 

[Jimmy W]

White Oak would work. I wouldn't use Red Oak. Black Locust would work great. Both would add weight. Probably easier to find Douglas Fir and it should do fine.