One strange and silly thing to remember about epoxy is that it works better if it has gaps to fill.Yes along the glue (epoxy) line. Doweling wouldn't really help because the epoxy is breaking. (I have a biscut jointer and could have used it but it was only 4 boards and I could line them up easily enough.)
I think it has something to do with the moisture in that end of the board.
Each rudder is made of half of a 10' 2x12. I cut it in half then ripped each into 4 pieces. I kept each boards pieces together so I could flip and turn every other board and have it not warp if it ever gets wet. When I epoxied them together I clamped both rudders at the same time with the same clamps. (Ie; 8 boards together.)
The other rudder is still fine...? Oh well, this one will be too. But the failure is the reason I have decided to use a heavy weave cloth to cover both of them. It's a Kevlar and glass weave. Crazy strong! (I'm told it's used in the floor for blast supression on the Striker personnel carrier vehicles.)
I got my tiller handle sanded after a random orbital sander failure... The head broke off! (Porter Cable... come on...) I didn't want to drive over to the shop and get the Ryobi one so I fixed this one. I used LocTite on the screws too. (Something they didn't do...). It works as good as it ever did. (Not as well as the Ryobi but it's what I found first when looking in the shop last week.)
I picked up some Mariners varnish and got one coat on tonight.
It looks good except for the odd bang and scratch.
I got my dock in today with the help of my dock mate Ron. It went well.
We are the first to get in again. (I don't know what those retired guys do all day...)
If the fit is near perfect, epoxy doesn't really hold all that well. For a well machined joint, a glue like resorcinol works a lot better, is UV and waterproof and cleans up with water until it sets (after that, you're grinding it off).
The bad thing is that it does leave a purple glue line. But if the fit is that good, it'll be a very thin line.
A question about the kevlar. I had alway thought it owed it great properties to the fact that the fibers could move past each other without separating. Once it's coated in resin, wouldn't it lose that property and just be the same as fibreglass cloth? Or is it that the longitudinal strength of kevlar is higher than fibreglass?
Thanks