A Simple Pair of Seven-Foot Oars

Discussion in 'Boatbuilding' started by Bob Smalser, Jul 3, 2004.

  1. Bob Smalser
    Joined: Jun 2003
    Posts: 79
    Likes: 11, Points: 0, Legacy Rep: 159
    Location: Seabeck, WA

    Bob Smalser Junior Member

    These are for the wedding-gift sailboat to the oldest son, so the family consensus is that store-bought oars or my cruder, painted workboat oars won’t do…I’ll have to bite the bullet and finish something that’s gonna take a beating in…ugh…brightwork. The yacht-finish masochists among you should be pleased.

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    I pick a couple weathered 8/4 X 6 old growth Western Red Cedar planks off their stack. Tight grained and clear stock I milled from a sunken log I salvaged 4 years ago. These rift-sawn planks were milled to be door stock for the new house…but I can spare a couple for a good cause.

    Why cedar? I have it on hand, and mast-grade Sitka Spruce, Port Orford or Yellow Cedar…all much stronger and more appropriate than WRC…are 8 bucks a BF. I have some good Doug Fir…but it is tres ugly finished bright, IMO…. and doesn’t plane near as crisply as the others. I can do some things to the cedar that will make it adequately hard and strong for this application.

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    Well…after planing off the weathering…the chalk line shows I picked one wrong plank. A board from a log I couldn’t overcome the taper in…and if I rip it straight there is a pin knot in the way and insufficient stock remaining for the blade. Fine for a door panel or an oar blade…but no good at all for an oar loom. I can go back out in the rain and muscle around a few thousand pounds of planks to find a better one, or I can make do. I decide to make do. An edge joined blade will take longer to do but will be stronger, eh? A joined oar also gives me the option of orienting the stronger edge grain to the moment of effort in the loom…like in a baseball bat…while using the face grain pieces on either side of the loom to minimize the chances of the blade splitting. That option is useful when making an exceptionally light oar…which these are not, and I don’t use it, as I want these oars to have some spring during use.

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    The first step in laying up the oars is to joint the fence edge and rip my looms from the straighter 8/4 plank…and there is zero movement after the rip, which tells me the stock is perfectly seasoned. If it were otherwise, I’d have to go find other stock. I rip a 16th oversize and joint all the faying surfaces on the jointer for a good layup.

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    I rehearse my glueup…

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    …glue up using Elmer’s Poly and leave it overnight. Why poly and not epoxy? Well, in the old days, we woulda used Plastic Resin Glue, which in edge joining…a joint not hard on glue…is also more than adequately strong. Even with perfectly jointed edges, it will take a bunch of clamping pressure to bring 8/4 stock into a good joint…poly loves high clamping pressure while using epoxy under those circumstances may starve the joint of glue. The soft cedar soaks up glue, so I use a lot of glue on all mating surfaces, and let it soak in a while before clamping, keeping a wet surface.

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    This next step looks silly, but works. Because of the softness of the cedar, I’ll epoxy a Purpleheart spline into the oarblade tip. It’s a crossgrain glue joint, but cedar is exceptionally stable and epoxy exceptionally flexible. In the process, I’ll use the heat gun to thin unthickened epoxy, flowing it deep into the end grain of the blade tip….as much as the wood will take…followed by thickened epoxy and the splines, which are cleaned with acetone first, as Purpleheart is oily.

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    And the resulting assembly is allowed to cure.

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    Now I’m ready to mark my centerlines, stapling my face pattern to one of the glueups and cut it out. I like the pattern found for ash and spruce oars in Woodenboat Issue # and modify it for weaker cedar by increasing the scantling size a bit. My looms will be sided 2” X 1 7/8” tapering to 1 ¾” X 1 ¼”…with a 4 ¾” inch blade width. For easy storage, I make patterns in two pieces on a long table and align them on the stock with a straightedge.

    Continued…
     
  2. Bob Smalser
    Joined: Jun 2003
    Posts: 79
    Likes: 11, Points: 0, Legacy Rep: 159
    Location: Seabeck, WA

    Bob Smalser Junior Member

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    After cutting out with the saber saw, I square and fair the edges with hand planes and spoke shave. You’ll always see two planes in my pics…the #3 is set coarser than the #4, which is set for a very fine shaving and is used in finishing. A #5 is used ILO the #3 for longer oars. Oars are best cut on a band saw, but you don’t really need one…just remember that the least precise your saw, the farther you should cut outside your lines…especially on curves…to be finished square to the line with hand tools with no unpleasant surprises when you turn the stock over and discover where your saw blade wandered.

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    I then use the cut and faired stock as a pattern for its mate.

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    The side profile or taper pattern is applied and marked on both sides of each rough oar…

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    …and the power jointer set up to machine the tapers. Set the unplugged jointer to take a 16th, then index the oar against the cutter head where the penciled taper first shows a 16th on the blade side of the loom. Make a tick mark on each oar indexed against the edge of the jointer fence as your starting point.

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    Turn the jointer on, open the guard using a push block held in your right hand and align the tick mark on the oar with the fence edge using your left. Then lower the oar face onto the cutter head gently with a forward motion, and push it through bearing down hard on the oar blade with the push block in your right hand.

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    Repeat using that 16th distance between pencil line and oar face each time, and you can taper the faces in about 8 passes per face so cleanly that they need no further work with the hand plane. Do a few dry runs, first, of course…. as machines can’t hear you cry.

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    I make an 8-Siding Gage (An 8-Siding Gage) , lay out my tapered, square looms and blade edges into octagons or tapers for planing….

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    …and rough out all the bevels with draw knife before finishing them with the plane and spoke shave. Very fast and efficient…but practice both using the drawknife in all 4 of its modes and reading grain before committing expensive stock to it. (The Drawknife)

    Continued…
     
  3. Bob Smalser
    Joined: Jun 2003
    Posts: 79
    Likes: 11, Points: 0, Legacy Rep: 159
    Location: Seabeck, WA

    Bob Smalser Junior Member

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    I finish the beveling with planes and spoke shave. I prefer to face plane the blade faces first to their penciled tapers laid out by the 8-Sided Gage, followed by spokeshaving the transition to its lines…

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    …leaving the looms for last. My final planing is a light swipe with the #4 to remove any remaining pencil lines. The oar button and leather will be 30 inches from the end of the handle, and I make an abrupt transition there from 8 sides to 16 sides and finally to an oval using spokeshave alone all the way to the transition. I prefer my loom ends to remain 8-sided…I wouldn’t want my oars confused with something done in a factory.

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    I’m careful to stay on the outside edge of my lines when beveling…and the end result on the right is a more pleasing (and stronger) 5-7-5 ratio than a true octagon. The left oar has been drawknived but not planed…note that I rough out the handles beforehand so a slip won’t take too large a chunk in that critical area. The right oar has been planed fair and clean.

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    Then I finish the handles with rasps and 60-grit paper, and then sand the oars with 60-grit on a sanding block…careful not to round over any edges.

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    After the rough sanding, I wet the wood to raise the grain using a damp towel, also raising any scratches and dents…and finish sand with 120-grit, easing all edges gently so they hold finish better. Raising grain between grits minimizes scratching, and removes all the fuzz that can telegraph through your finish the first time the oar gets wet.

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    WRC is a bit soft and splintery for use as an oar, so I encapsulate the finished oars in epoxy prior to spar urethane varnish. I simply brush on unthickened epoxy heated to 110 degrees with a heat gun and allow the wood to soak up all it will take of it. Messy, and downright ugly to sand afterwards, as the wood usually off gasses some, making bubbles tedious to sand out….but a rock hard and strong surface to varnish over. It doesn’t turn cedar into spruce, but these oars will likely serve a long time.
     
  4. Bob Smalser
    Joined: Jun 2003
    Posts: 79
    Likes: 11, Points: 0, Legacy Rep: 159
    Location: Seabeck, WA

    Bob Smalser Junior Member

    Here's the finished product along with the boat hook for when something sturdier is required:

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    I like soft cotton on delicate hands doing heavy work, so I whip the handles in pure cotton twine soaked in water like the leather. Leathers are baseball-stitched and the skived button mounted with brass box-hardware tacks, making the buttons removable if required by some oarlocks.

    They'll dry out and shrink up a couple days in the sun, then I'll douse the leather in Bee Oil followed by Westco's beeswax boot treatment. The oversize oarlocks will also be leather lined to minimize denting of the oars.
     

  5. Corpus Skipper
    Joined: Oct 2003
    Posts: 606
    Likes: 8, Points: 0, Legacy Rep: 173
    Location: Corpus Christi TX

    Corpus Skipper Hopeless Boataholic

    Wow Bob, nice work. My anniversary is coming up........ :D
     
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