Canoe Update
Jun. 7th, 2011 08:20 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
catsittingstillThe canoe ... well, I didn't do much of anything on it last week.
This week I started trying to do what I meant to do last week. However "scarf gunwales" (meaning cut out the bad parts of the gunwale wood, like knots or wild grain or cracks that might make a weak spot where the gunwale would break later, and epoxy the good wood back together to make long enough parts to be gunwales), which I had thought would take a day or perhaps two at the outside, has been much more of a production than I expected.
Gunwales are under a lot of strain--they're bent in the first place when you take a long thin piece from a straight board and fasten it to the edge of a shape that curves both in and up at the ends, and then they take a lot of the knocks and abrasion and flexing that would otherwise go straight to the hull. So gunwale scarfs are cut at an angle--this provides a bigger area of glue to take the strain, and it makes the wood more edge grain like than end grain like (which is good, because end grain drinks glue like anything and sucks the epoxy away from the joint, weakening it.)
The usual angle (according to my favorite book) is 7:1, meaning that the cut runs seven times as far down the gunwale as the gunwale's width (so for a 3/4 inch gunwale, the top of the cut is 21/4 inch or 5 1/4 inch farther along the gunwale than the bottom of the cut.
This is a pretty sharp angled cut, and it needs to be made straight and clean. I spent most of a day just figuring out how to make a jig that would let me make this cut with a handsaw. Then I discovered that the cut wasn't straight enough (my longest handsaw is kind of bendy.) So I spent another half day trying to figure out other ways to make the cut, giving up, and looking up how to make a shooting board (a jig that lets you plane an edge to an exact angle.) The shooting board works fine, so I'll be going with that.
By this afternoon I had cut enough good pieces to make one inwale and most of a second. The good news is I'm pretty sure I'll have enough good wood to make the inwales. The bad news is I think it will take closer to a week than a day to make them. It's not just making and cleaning the cuts by hand, it's epoxying everything together. I have a jig to hold everything straight and flat but it will only hold two scarfs at a time, and I can't move the setup until the epoxy has cured twelve hours or so.
Also about 3:30 it gets too hot in the shop for me to be willing to work any more.
Next time I think I'll just spend the money to get long enough wood with good grain and no knots.
In the meantime I am working on a couple of new songs,neither of which is anywhere near being ready to post. I am also trying to get ready to record tomorrow morning, speaking of which it is time to go practice. Tomorrow I will see whether the sealing earbuds screen out the metronome clicks or not. And try recording SwanMay.
Plus I really need to keep working with Audacity so I don't forget what I've learned.
This week I started trying to do what I meant to do last week. However "scarf gunwales" (meaning cut out the bad parts of the gunwale wood, like knots or wild grain or cracks that might make a weak spot where the gunwale would break later, and epoxy the good wood back together to make long enough parts to be gunwales), which I had thought would take a day or perhaps two at the outside, has been much more of a production than I expected.
Gunwales are under a lot of strain--they're bent in the first place when you take a long thin piece from a straight board and fasten it to the edge of a shape that curves both in and up at the ends, and then they take a lot of the knocks and abrasion and flexing that would otherwise go straight to the hull. So gunwale scarfs are cut at an angle--this provides a bigger area of glue to take the strain, and it makes the wood more edge grain like than end grain like (which is good, because end grain drinks glue like anything and sucks the epoxy away from the joint, weakening it.)
The usual angle (according to my favorite book) is 7:1, meaning that the cut runs seven times as far down the gunwale as the gunwale's width (so for a 3/4 inch gunwale, the top of the cut is 21/4 inch or 5 1/4 inch farther along the gunwale than the bottom of the cut.
This is a pretty sharp angled cut, and it needs to be made straight and clean. I spent most of a day just figuring out how to make a jig that would let me make this cut with a handsaw. Then I discovered that the cut wasn't straight enough (my longest handsaw is kind of bendy.) So I spent another half day trying to figure out other ways to make the cut, giving up, and looking up how to make a shooting board (a jig that lets you plane an edge to an exact angle.) The shooting board works fine, so I'll be going with that.
By this afternoon I had cut enough good pieces to make one inwale and most of a second. The good news is I'm pretty sure I'll have enough good wood to make the inwales. The bad news is I think it will take closer to a week than a day to make them. It's not just making and cleaning the cuts by hand, it's epoxying everything together. I have a jig to hold everything straight and flat but it will only hold two scarfs at a time, and I can't move the setup until the epoxy has cured twelve hours or so.
Also about 3:30 it gets too hot in the shop for me to be willing to work any more.
Next time I think I'll just spend the money to get long enough wood with good grain and no knots.
In the meantime I am working on a couple of new songs,neither of which is anywhere near being ready to post. I am also trying to get ready to record tomorrow morning, speaking of which it is time to go practice. Tomorrow I will see whether the sealing earbuds screen out the metronome clicks or not. And try recording SwanMay.
Plus I really need to keep working with Audacity so I don't forget what I've learned.
