Attaching the Skeg

The skeg is a triangular-shaped piece attached to the bottom of the hull near the stern; it has three important functions:

1. This is one of the pieces that gets stuck in the mud.  (The other piece is the keel, which is forward of the skeg).
2. It aids the boat in tracking in a straight line, which is especially important when rowing.  When sailing, it also provides some lateral resistance.
3. It looks good.

Like Wee Lass, Tammie Norrie has a wineglass transom.  The transom has a reverse curve down low, so that the transom resembles a wine glass when viewed from behind.  The skeg performs the purpose of serving as the stem to the wine glass.  Okay, you may have to use your imagination.

Wee Lass’ transom, also showing the skeg.

The skeg will be attached by both epoxy and screws.  Because the skeg is so deep, the screws will need to go from the keelson into the skeg, rather than vice versa.  That means I need to crawl under the boat to drive the screws home.  With my rubenesque physique, that won’t happen when the boat is completely planked.  The skeg needs to be fabricated and attached now, while I’ve only got the garboards hung.

I started making the skeg by pulling out the plywood that I did the lofting on; the layout of the skeg is shown there.  The lofting was traced onto some sheets of mylar.  It would have been neater and perhaps a little less confusing to trace onto new sheets, but the art supply store is located near the Big Mall and I really didn’t want to fight the traffic.  So I traced the skeg onto the sheets that I had used for tracing the molds, and hoped I wouldn’t get messed up. Once I had the layout traced onto mylar, it was simple enough to transfer that onto pattern stock, which was 1/4″ plywood.

2016-05-21 Tracing the skeg from the lofting.

Offer up the pattern to the boat, and if you’re a better boatbuilder than me, the pattern will fit perfectly.  If not, trim a little here and a little there until you get a good fit, and at this time you’ll be glad you’re trimming 1/4″ pattern stock rather than Very Expensive boat building lumber.

The skeg is 1-1/4″ thick.  Nominal 2x lumber is 1-1/2″ thick, so it would be a simple matter to buy a piece of 2x the correct width, run it a couple of times through the thickness planer, and I’m off to the races.  When I built Wee Lass I used yellow pine from the big box store, and it worked fine.  But after the debacle with the building jig, I swore an oath that not one piece of wood from the big box store would see a permanent home on my boat.  Both the skeg and the keel would be made of douglas fir.  Douglas fir is a relatively soft wood, but the bottom edge will be protected by a strip of half-oval brass.

So I trotted off to the Purveyor of Very Expensive Lumber only to find that they did not stock douglas fir in 2-by thickness.  The skeg would have to be made of two layers of 1x lumber.  The process was similar to that of making the stem.  Since the thickness of the skeg is 1-1/4″ where it meets the hull, I milled the lumber down to 5/8″.  Cut two pieces oversize, then clamp one piece to the pattern and use the router with a flush trimming bit to make a copy of the pattern.  Then butter up with epoxy, and glue on the other piece.  When the epoxy cures, use the router again with the flush trimming bit riding against the first piece.

2016-05-22 Pattern and one side routed; oversize piece laying under pattern.

2016-05-22 Glue-up

Although the skeg is 1-1/4″ thick where it joins the hull, it is tapered to 7/8″ on the bottom edge.  The glue line serves as a convenient centerline; a distance of 7/16″ is marked either side of the centerline and the bulk of the material is removed with the block plane.  A few minutes with the palm sander makes it look pretty.

Finally, the skeg was attached to the boat with epoxy, and secured with silicon-bronze screws.

2016-05-25 Skeg attached to the hull. I’m already thinking about installing the second strake, the batten for that strake is tacked in place.

Now that the skeg is installed, I can start thinking about the remaining strakes.

2016-05-29 Wineglass transom on Tammie Norrie.