Building a stitch and glue kayak

Advice
#1

I am building a baidarka plywood stitch and glue kayak. I have just assembled the joints. Do I fiberglass both sides of the joint?

Thanks

Frontrow

#2

I would
I built two stitch and glue sea kayaks from kits. One was a Chesapeake Light Craft and one was a Pygmy.



The instructions and materials for the Pygmy kit called for completely glassing the interior as well as the exterior of the hull. The CLC kit included fiberglass tape, about 2 inches wide, with finished edges to be used on the hull interior as well as 6 oz/yard E-glass to be used to glass the entire exterior of the hull.



The tape I am sure would be enough to reinforce the interior joints of your boat.

#3

Whenever Possible, Tape Both Sides…
…of the seams. In doing the VOLKSKAYAK, we tape all seams on both sides with 4 inch 6 oz. cloth. I also fiberglass the interior floor of the cockpit, and run an extra strip of 3" cloth down the centreline of the keel. My first VK, the RightWind, is still in good shape 10m years after I built it.

#4

thank you
Yes, I went ahead and fiberglassed both sides of the joints. I amazed at how the epoxy causes the fiberglass to vanish.

#5

Stitching question
This may be a dumb question, but can anyone tell me how in this construction method tape is put over the stitches smoothly? I imagine a pocket of air at each stitch? Is the stitch removed before the tape is put on?



Thanks

#6

thin copper wire
Use thin copper wire for the stitches and twist the copper wire ends to tighten or loosen the stitches to get a nice, fair joint. Use epoxy to glue the seam and after it is cured snip the copper wire and pull the strands out before glassing. There will be a little dark dot where each copper strand penetrated the wood.

#7

process
On my boat I glued the seams with thickened epoxy and then removed the wires. The seams were filled and faired smooth before applying the glass to prevent voids.



Examples;

http://www.pygmyboats.com/Construction.htm



http://home.roadrunner.com/~wreinert/osprey_b.htm


#8

for a comparison
if you only glassed one side you’d have to put on such a thick backing plate that it would be as rigid as the plywood it’s joining. Earlier Pygmy kayaks had the long skinny panels joined by a another 3" wide piece of 4mm ply. The CLC Arctic Hawk kit uses a VERY thick backing plate made out of successive layers of 3" 9oz tape.

You can use one layer of 4oz cloth on both sides to join a butt joint but you have to be VERY careful when handling the long panels.

#9

different methods
for panels that meet at shallow angles like deck panels and the ends of hull panels it’s much neater to remove the wires after an initial glueing of seams is done. That way cloth or tape can lay neatly to join the panels. Instead of using strips of glass tape for joining the underside of multipanel decks I’d rather use 4oz cloth.



For narrower chine joints CLC kits use copper wire that is cut and filed/sanded then covered with epoxy putty or wide/heavy 3" 9oz glass tape. Pygmy kits use softer iron wire that is removed and narrower glass tape.

#10

Kudzu Craft has a new book
Check out:



http://www.kudzucraft.com/



Jeff has a new how-to book out that may be helpful.

#11

baidarka S&G?

#12

Is your boat a kit or are you building
it from drawings?

#13

In my experience
if you put a thickened epoxy fillet on the inside of the joint, cover it with glass tape & epoxy, and glass the entire outside of the bottom & sides, you’ll be fine.