Kirk,

Congrats on starting your Walrus.

I've built a couple of Putz style kayaks. I used epoxy for all of the glue joints on the first one. I used polyurethane glue for the last one. I have repaired the last one more than the first. I have had some problems with joint failures. When I repair the joints, I used epoxy, it makes a much stronger joint. Epoxy is also much more forgiving than polyurethane glue, you don't have to clamp as tightly. The areas that have failed were small joints in places that were subjected to flexing. Most of my polyurethane glue joints are holding up okay, but repaining them after the skin is on is a real pain. None of the epoxy joints on the first kayak have failed, the epoxy just works better. The polyurethane appears to be quite waterproof, but it can't handle flexing as well as epoxy. The 1 1/2 QUART EPOXY KIT 1 qt. resin and 1/2 qt. hardener (fast or slow) from Raka is only $27.00. That should be more than enough for a Walrus. Or you could try their EPOXY SAMPLE KIT, the kit includes twelve ounces of our standard marine epoxy resin 127 with fast 610 and slow 606 hardeners, a small sample of silica and micro-bubbles, and a sample of standard 6 oz. fiberglass for only $ 10.00 and shipping is included in the price.

I have used polyurethane glue for laminating blanks for greenland style paddles with no problems. I was able to use a lot of clamping pressure for those though.

I plan on doing some testing of DAP Weldwood Plastic Resin Glue. Dynomite payson uses this on his Instant Boats, he say's it'll hold up unless you boil it. If I was in a kayak in 212 degree water, I'd be headed for shore immediately anyway.

I used western red cedar (WRC) and mahogany on my first one with excellent results, I used only WRC on my last one with acceptable results. Redwood should work as well as WRC

On the last one (all WRC), I decreased the stringer height by 1/8" and increased the width by 1/8". I ended up with a very light kayak 27 pounds. I also narrowed the kayak by 2", increased the flare, deadrise, bow & stern height, and length, and lowered the depth to sheer at the cockpit to 6". It rolls VERY easily. I made the deck flat with a raised section in front of the cockpit. I used rib style floors in the cockpit area, to lower the seat. This works, but has created some durability problems.

I have used both canvas and polyester for the skin, and prefer the polyester. It is cheaper, stronger and lighter. I used water based polyurethane to seal the polyester. For the canvas kayak, I sealed the skin with Elast-o-Seal and Snow-Roof.

If you have any more questions, just ask.

Mike

: Hello everybody,

: I have commenced with building a 17' skin on frame Walrus ala Putz and am
: making steady progress. I have decided to use redwood for the frame since
: it is readily available at a good cost and seems to have nearly the same
: properties structurally as pine.

: So my question is what to do about the glue for the frame. I was going to use
: epoxy but got to looking at polyurethane glues which are much cheaper and
: seem a bit easier to work with. Does anybody have any experience with
: these types of glues for the frame on a skin on frame boat? I am concerned
: about how these glues hold up in water as well as their overall strength
: properties. Is this an area that I should be skimping on?

: So far everything is going well with the forms. I scaled them down a bit to
: use less plywood. Im enjoying the process thus far and appreciate
: everyones advice.

: Best regards,

: Kirk