How do YOU cut chine or other notches?

I figured. I was just messing with you...

Unfortunately, a number of things conspire against me in this particular instance. First, I don't think that far in advance. I could have, for example, very easily cut chine notches into the corner posts at the transom if I hadn't already epoxied them in place. (The pocket on the transom itself, since it doesn't go all the way through, is another matter.)

Second, the geometry doesn't seem to lend itself to machine cutting. The transom, as mentioned, takes a notch that doesn't go all the way through the material. The stem is roughly triangular in cross section (the "points" of the triangle having been sawed off to make flat shoulders) with six flat surfaces:

Code:

.   _
.  / \
. /   \
. |___|

That is a terrible ASCII drawing but you get the idea. So the pointy end at the top is the stem face. The beveled sides are where the chines (and eventually planking) land. The top face (end grain, the part you're looking down on above) is cut to an angle to match the rocker on the bottom of the hull. The chines come in from either side at an angle (right or left as you're looking down) to the stem and at an "elevation angle" (i.e. the chine curves up from the hull bottom to meet the bottom of the stem).

You probably know all of this already and I'm just exercising my typing fingers. Anyhow, my problem is cutting a nice, neat pocket for the chine to sit in where it meets the bottom of the stem. The pocket isn't square to any reference surface (although the inside face should probably be parallel to the stem bevels). I guess I could jury-rig some kind of router sled and use a straight-cutting bit to hog out most of the material, then finish up with a chisel. Beats me.

EDIT: Stupid post editor removed my spacing from the "drawing" above. It looks even worse than when I started.

 

It looks fine, for a house by a waterfall!

 

Okay, so I hemmed and hawed and screwed with it last night for a few hours, and I finally got the two notches in the transom cut beautifully using a couple of routers and some edge guides. This worked perfectly because the transom has nice, straight edges and a large, flat surface for the router base to bear on.

My only issue now is whether to re-make the stem. Nobody will ever see it, and I'm sure the epoxy and screws will hold it just fine, but it still makes me shudder. I wish I could figure out the geometry to cut the notches first, while the stem blank still has straight, square edges, and THEN cut the bevels, but I'm not sure I'm that smart.

 

The compound angles are always a problem. If I can not get a protractor or other measuring device on them, I usually trial and error the fit, cutting a little at a time, until it is "close enough".

On your stem, if can you still access the sloppy joints so you can sand or file them so they look a bit nicer without disassembling them, just do that. It is always an option, or cover it with a number of layers of thick paint, that can also hide a number of ills.

I would not beat yourself up too much about the appearance. The boat is not a peice of fine furniture; I think many perfectionist wood boat builders are too obsessive with fit and finish, and they intimidate the rest of us. If you go to maritime museums and carefully inspect the fit and finish of historic work boats, you see no such obsession with appearance. They are not attractive at all, just practical and sturdy designs that get the job done with the minimal amount of labor. To me that is the most attractive boat of all.

 

Troy,

I have a saw set and a saw vice - no one else knows what they are!

 

I'm not exactly sure what you're trying to do, but it seems you're attempting to pocket cut an odd shaped mortice or just a notch.

A notch is fairly easy, in that you have a couple of shoulders and a back wall cut. A hand saw, possably a Japanese saw if you're comfortable with these, will make the shoulder cuts quickly. Several more cuts, just like the shoulder cuts will define the back wall, if done with care. You can then knock the kerfs out and clean it up with a chisel.

Of course picking up the angles can be a chore, but thoughtful use of a bevel gauge and some practice stock might be helpful.

A mortice is a different beast and usually best done with a chisel.

Personally, I don't see why you need the notches. The chine logs can land on the stem side and receive a fastener or glue. There's no need to notch the stem, just bevel the back side of the chine log to match the stem side.

Lastly, considering where this portion of the boat is, no one is ever going to see this joint, so maybe some goo factor to the rescue is in order.

 

In order for the planks to land on the stem, the chine has to be let in. I could've compensated for this by making the stem narrower by the width of the chines, and then fastened the chines to the sides of the stem, but I'm way beyond that now.

No matter. Enough epoxy and then a few passes with a power planer and a swig of Scotch and we're back on track. I've decided just not to think about it anymore.

 

the healing powers of Scotch are amazing ...lol


I am a little late to this discussion , but a method I always found to work for me when I did wooden plank or strip hulls was after temporary setting the first piece I would measure the exact angle and then cut the joining piece to the same angle with a little to space for when I cleaned it up.

also on a hard chine hull sometimes you mite consider fair out or feathering down the chine as it comes to the bow

 

If I were doing this again, here's how I would do it. First, I would mill the stem, cutting it a few inches too long. I would cut the bevels on the stem so the cross-sectional shape is correct. Next, I would cut the top (sheer) end of the stem to the appropriate angle and temporarily mount it to the building jig.

I would plumb and brace the stem in position according to the plans/offsets, and then I would spring the chines into place, holding them with clamps. Then I would mark on the stem where the chines lay across it, remove the chines, and remove the stem from the jig.

Next, I would clamp the stem on a work table (blocking under the beveled faces appropriately) and use a router to hog out the waste. With the router riding on the beveled face, the angle at the bottom of the cut would match the angle of the stem face perfectly, and the bit could easily be set for just a fraction more than the molded dimension of the chine. I don't even think I'd bother to square the inside corner left by the bit; I'd just use a file or a rasp to round over the sharp corner on the chine.

 

Welcome to the club. Texas and California? Between the two of us, we take in a good bit of territory...

I've found that some beautiful old saws have work-hardened teeth, that'll snap like a clarinet reed if you try setting them. Fortunately you can tell the ones with brittle teeth the minute you start sharpening them, by the sound and feel of the file.

I always figured there must be a way to anneal the teeth and start over on an old saw like that, but I'm no metallurgist.