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by Tom Clarke - Newark, New Jersey - USA

Raven, a Ross Lillistone “Flint” was completed Summer of 2013. I sailed her lug rigged, but enjoyed the rowing even more. (She is a delight to row!)

Raven at Round Valley in New Jersey

The oars called for in the Flint plans were seven feet, pictured below before being oiled with Watco Teak Oil. They were proportioned correctly with the oar locks located on the inside of the gunnels. The oar locks were screwed to the gunnels with 1" #10 screws. However, after a couple months of rowing, the screws started to work lose in the Western Red Cedar gunnels. I tightened them, but they continued to work lose. I also found that on the return stroke, the oars would sometimes hit my legs, so I decide to raise the oar locks by putting 1.5" teak blocks under the locks. I bolted the locks through the blocks and the gunnel. This required that the locks be put on the outside of the blocks. Unintended consequence; lock to lock distance increased about 4" and rowing with the 7' oars was awkward. The handles were now separated by 4". Doesn't seem like much but it made a big difference.

The original 7' oars according to the Flint plans

I decided to make “New Oars for Raven”. I did a search for oar plans and found these. They are for 7.5' oars. I expanded the spoon and loom length proportionally to create 8' oars. I ripped two clear, straight 8' x 4" x 3/4" Radiata pine planks to 1.5" width, swapped two of them end-for-end so the grain would be opposing each other, stacked them (with wax paper between the two stacks), slathered Titebond 3 on the facing surfaces and clamped tight overnight. Result was two 1.5" x 1.5" x 8' straight oar blanks.

Layup of four ¾" by 1½" by 8’ for the two oars

On the table saw, tapered the oar blanks according to the plans. Result was a 1.5" square that ran from the handle end to the lock location and tapered from lock (1.5" wide) to 3/4" wide at the spoon end. I kept the glue joint parallel to the blade face.

Then I used a band saw to cut the curve for the spoon blade. The end of the loom was now 3/4" by 1/8".

The band to be glued on the face of the blade came from 1" by 1/4" Western Red Cedar, tapered down to 1/8" at each end.

The blades were cut from 1/4" Okume, after checking that it would make the bend in the blade. I penciled in the edges of both the loom and the 'band' on the blade to act as index lines for masking (the blue stuff) to minimize glue spreading.

A trial layup (see below) found that the loom was not tight up against the blade about 6" from the end of the loom. Using a pair of wedges, I was able to force the loom up against the blade. I glued them and let dry for two days. A sigh of relief when I undid the clamps and it retained the required curve.

Layup for gluing the blade to the loom

Using a draw knife, thumb plane, plywood 1.5" template and sandpaper, I rounded the loom starting at the lock position out to the start of the blade. See below for tools and shavings.

Tools used for rounding the loom

I then formed the handles according to the (TSCA) design, sanded everything, applied two coats of Watco Teak Oil to everything except the handles. Then two coats of urethane varnish on the blades. The picture below shows the shape and curve of the blades.

Finished blades

When all was dry, tested the oars at Spruce Run Reservoir (New Jersey) and was delighted with the improvement in rowing. That improvement came from a combination of reduced oar weight, longer length and spoon blade vs straight blade. The original oars weigh 3.5 pounds each, while the new oars, a foot longer, weigh 3.25 pounds. In addition, with the modification described below, the balance point is much closer to the lock position and therefore they feel lighter than they actually are.

But in testing the new oars, I found the shape of the handles very (VERY) uncomfortable. I decided to replace the handles with new handles.

I cut the handles off, square to the end of the loom. I then tapered (8:1) both sides of the loom to a knife edge (parallel to the lamination joint for the oar blank) on the table saw, creating a 'V'. I then cut four 12" lengths of 1.5" by 3/4" oak, tapered (identical 8:1) each on one 1.5" side. Using TB3, glued the two pieces of oak (tapered side to tapered side) and then, at the same time, glued the resulting 'hollow' V over the taper on the loom. clamped and let it dry overnight.

The next day, using a chisel, rasp, file and sandpaper, shaped the 5.5" handles. See the picture below for the handle shape (1" to 1.25" diameter) and how the oak was spliced into the loom.

New handles

To protect the oar at the lock, I wrapped the loom with mason's string, then laid in a Turks Head (a Jim Michalak technique) using 1/4" shock cord from Duckworks. The Turk's Head stop works okay, but must be tied very tight, else it will slowly slide onto the square portion of the loom.

Using Duckworks 5/32" Solid Braid Polyester Line and Nylon Micro Clamcleat with Fairlead, I created adjustable stops for the oars which enable quick adjustment for changing the 'leverage' on the oars. This works really well.

The picture below shows the Turks Head stop, how the adjustable stop clamcleat is mounted on the bottom side of the oar with the line looping around the lock and back to a loop around the oar, jammed against the clamcleat, tied with a 'Poacher's hitch'. The toggle hanging below the lock is a 7/16" cylinder, bored down the center to take a short piece of the polyester line. A slot is cut half the length of the toggle to enable it to pivot and prevent losing the lock.

Turks Head oar stop

For the next pair of oars I make, I'll splice in oak handles again, but carry the oak out to just before the lock location, in order to add extra weight on the handle end, yet keep the rest of the oar light.

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