Construction and Design Journal – 14ft Dory for Rowing and Sailing – Part 10

by Roy Heberger - Boise, Idaho - USA


I had decided earlier to widen the stem to give more purchase to the planks ahead of the bearding line, so today I lifted the lines of the stem to two oak planks of ¾-inch thickness, gave them shape and attached them to each side of the stem using glue, screws, and clamps.  The stem is now made of four laminations of ¾-inch oak.  On the aft edge of each new stem member, I attached the port and starboard members of the frame at station 1, which has no futtock.  I then supported each of the new frame members with scrap lumber attached to the strongback.

The next step is adding RBC to the transom sides and beginning the rib-bevel work.


I added RBC to each side of the transom and glued, screwed and clamped the stock overnight. This will give added width and a really nice appearance to the finished boat.  My new neighbor, Ben Shed, loaned me two sliding clamps to add to the array, which was very helpful.


To test a concept, I scarfed some RBC today and glued and clamped it overnight.  I used only a 3-or-4-to-1 ratio. I’m back to a chine-log concept for the bottom and the knuckle.  I plan a two-step process for the bottom chine.  First, I will rip one of the chine ¾” x 1-1/2” chine planks I made so that I end up with two planks that are square in cross-section – ¾” x ¾”.  This should bend in two directions, which is what is needed for the chines.  I intend to insert the square stock first by cutting into the futtocks and bending the stock from frame 4 forward and then frame 4 aft.  I will fasten with temporary screws and glue at each frame the stem and the transom.  I will add to that additional stock so the cross-section will look like this (upside-down on the strong back:

The angle and bevel of the second chine member will vary frame by frame and at the stem and transom.  This will show the fair curve of the bottom and give purchase for the gluing and screwing garboard.  I’m doubtful.


Well, some time has passed since the last entry, but I’ve made progress.  Using a draw shave and low-angle plane and a baton, I have added bevels to the ribs, transom and stem (jack plane for that as well).  I fear I’ve taken off to much on the port side of rib 6 and the starboard side of rib one, so I will be adding a thin strip of RBC using epoxy, and I will re-bevel those frame members.

I acquired ten panels of marine plywood at an outlet in Portland, Oregon.  I located the place by accident via the Internet.  It was not listed under “marine plywood.”  I bought four, 6mm panels (cabin planking); four 9mm panels (hull side planking), and two 12mm panels (bottom planking).  The panels are Okume (African mahogany) made in France by Joubert, and they are 2500 X 1220 mm Lloyds Register Type Approved BS 1088.  The outlet in Portland is Crosscut Lumber.  I paid just under $600.00 at a substantial savings for the same product at Anacortes.  Whew!

I hauled the plywood myself.  The trip coincided with a week on the Oregon coast, so I was traveling anyway.  I used the river dory trailer to haul the panels and it worked just fine.

I have scarfed the two 12mm panels together, and the press is still attached after 48 hours.  I used the power planer to remove most of the material on the two panels clamped together to obtain a 12-1 ratio.  While it appeared flat prior to gluing, the scarf now appears to have had a very slight hill, such that the ends may be suspended somewhat.  If that is the case, I will fill with epoxy – first without wood flour and then with wood flour.  Frankly, I did a much better job of scarfing a plywood panel when I built the solo dory in ’01.  Guess I need to work more cautiously and be more critical before gluing a scarf.

As a side note:  I started making oars for Bob’s runabout.  They are composed of clear pine 1” X 2” X 8’ boards laminated with epoxy.  In the blades I added two thin strips (1/3”) of RBC for appearance and to give added strength.  I may add four very thin strips of RBC to the outside of the now square-in-cross-section shafts before shaping as well.  This will be good practice for the oars I build for this boat.

Okay, that catches this up to date.


Steaming the False Stem
False Stem
Base Paint
Base Paint

BOTTOM PANEL SCARFS – April 16, 2004

I took the plywood panel presses off today and the scarf joint is not too bad – better than I thought it may be from looking at the ends while it was in the press.  So, I started adding a still-runny, epoxy/wood flour mixture to one side of the joined panel to fill the depression between the end of one panel and the beginning of the scarf on the second panel.  I will do this on both sides to bring up the surface to obtain a single plane, and I will do so in increments to build up the epoxy so as to completely flatten the joint.  Later – after the bottom is fastened to the boat and the bout is righted – I will use fiberglass on each side to help strengthen the joint.  I don’t think I want to add that thickness before the bottom is fastened to the frames, keelson, and knees. There is not much dead rise to this dory, so I am not concerned about too much of a bend.  The outside of the bottom and garboards will be glassed.  Also, I am considering having the scarf at the aft end of the boat where I may add a skeg to the flat keel board.

Part 1 – Part 2 – Part 3 – Part 4 – Part 5 – Part 6 – Part 7 – Part 8 – Part 9 – Part 10

Part 11 – Part 12 – Part 13 – Part 14 – Part 15 – Part 16 – Part 17 – Part 18 – Part 19


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