repair of wooden boat

I’m hoping someone out there can help me. I have a wooden kayak, made from Chesapeake Light Craft plans…I didn’t make the boat. Recently a friend dropped the boat and a bolt punctured the hull making an approx. 3/8" hole through the ~ 1/8" marine plywood. It doesn’t appear that any additional damage was done. How do I go about repairing this? I know I need a means to plug the hole…and then seal the repair. With abit of guidance I think I can do this job myself but I don’t want to head off in the wrong direction.

Many thanks!

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3/8 isn’t bad. I would clean out the hole, sand around the hole to about 1/2 inch greater diameter than the hole diameter on both sides, mix up some epoxy with some wood flour to get it to a peanut butter consistancy (you might be able to almost color match it with the rest of the hull), back up the hole with some masking tape on the inside of the hull, slubber in the thicken epoxy to a thickness a little higher than the outer hull, let it cure, sand flush, put on other coat of unthickened epoxy over the area both inside and out, sand smooth, varnish and you’re all set. That’s what I would do.

Fat Elmo

it kind of matters where the hole is. I suspect there’s some flayed split wood on the inside. For example if the hole is a clear puncture on the outside there’s going to be some lengthwise splits around the hole on the inside. The laziest repair would be to sand around the hole and pull up split wood around the hole. Make a wood patch out of 1/8" ply about 2"x 4" if the splits travel lengthwise an inch from the hole and epoxy it back on with thickened epoxy then fill the hole on the outside with thickened epoxy after the inside is cured.

The Chesapeakes have a funny lay up of interior reinforcement with 3" 9oz tape on the inside seams and only 6oz glass in the cockpit. That leaves the compartments, especially the aft compartment vulnerable with no glass cloth on the wood inbetween the chine and keel tape.

drop the 's’

I would add some glass cloth to o increase the strength of the patch (both inside and out). The repair should be easy to do.

3/8" hole with cracked wood
requires some backing,wood or glass,just filling with a plug of epoxy is doable for a clean 1/4" drilled hole but with 3/8" puncture and cracked wood on the inside the plug will crack at the edges unless it’s got a big blob of thickened goop providing some backing.

The Chesapeaks use wood and glass inefficiently as designed, that’s why they will weigh a few pounds more than other paneled deck designs when glassed for the same level of durbability.

3" 9oz tape is a legacy of construction where that was the only glass used to join panels in the original designs, as the designs evolved 6oz glass was added but the overlap of 9oz tape and 6oz glass puts a lot of glass on the interior where the boat is already very strong with fillets but for some reason the bottom panels in the compartments are left unglassed. I bet one could glass the interior with only 6oz cloth over tiny fillets and save the weight taken up with 50’ of 3" 9oz tape available for other applications.