This blog is devoted to my John Welsford designed 15' Navigator yawl Ellie. I built her in my garage over a period of 18 months and launched her in 2011. She sports a sliding gunter main, roller furled jib and sprit-boomed mizzen. Her construction is glued-lapstrake over permanent bulkheads and stringers. This blog is a record of her construction and her voyages here in the Puget Sound area and (hopefully) a useful resource for fellow Navigator builders.

Wednesday, October 27, 2010

A little more work on the transom

Tonight I cut two more holes in the transom. A 1" drain hole, and a square hole for the boomkin.
That makes a grand total of 17 perforations through my transom. Six for the Duckworks motor mount, eight holes for the gudgeons, and three more for the tiller, boomkin and drain!  I hope the boat will still float despite all these holes!

Another challenge was how to trim all the planks flush with the transom. I thought about using a saw but was afraid of scratching the surface of the transom and chipping the planks. Then I thought I'd carefully whittle away at them with a sharp chisel. That would have taken forever.  I ended up using the Gain Machine

I set the Gain Machine so that the router bit was flush with the bottom of the base, like this:

Then, holding the base firmly against the transom, I used the Gain Machine to route the protruding planks flush with the transom.

The planks were perfectly flush a few minutes later.


  1. Looking good so far! Remember, the transom is not immersed at the design water line, so holes there won't be a problem. ;) Now that big hole in the bottom of the boat...

    Quick question regarding the motor mount: Are you using the 0 or the 15 degree version? Also, what is the vertical distance from the top of the mounting plate to the bottom of the lower gudgeon on that mount?

    God bless!

  2. Hi Wayne,
    Back when I bought my mount, only the 15 degree version was available. I would much rather have the 0 degree. I have to make tapered wooden blocks to mine. The distance from the top of the mount to the waterline should be 15 inches. That is the standard transom height for a short shaft outboard.

  3. Joel:

    Looking at the plans, it looks like the transom is raked aft about 5 degrees. Considering ideal angle for an outboard is between 10 and 15 degrees, it looks like the options are to shim the bottom of the 15 degree mount out, or to shim the top of the 0 degree mount out. There might not be any real benefit to the 0 degree unit for this boat.

    Looking at your pictures, it looks like none of your mount screws penetrate the transom below the seat tops. This means I can retrofit it (relatively) easily later if I see the need for an outboard. This is one decision I can make later.

    Thanks for the information.

    God bless!