Sunday, March 13, 2011

Oar Making - Part 1, Lamination

I'm making some oars for axillary propulsion. Hopefully these will be adequate and I won't need an outboard motor.  I'm going to install some oarlocks on the tops of the coamings ... details on that in a later blog post.

I've spent a lot of time pondering a number of issues regarding the oars:
 - if oars for this boat even possible, since its so wide (6'6" beam) and has coamings,
 - the length of the oars necessary,
 -where the rower would sit ... there are no thwarts to sit on like on a row boat,
 - whether to buy or make the oars
 - and, most vexing, where to store the oars out of the way while sailing.

I've never made oars before, don't have the right tools probably and have no idea what I'm doing, but I decided to make some 8 foot long oars out of some rather cheap pine 1x8 boards from the local home improvement store.  Total cost is about $40 for two oars and a weekend of work.  8 ft oars will not store anywhere on the boat.  So while sailing, I'm just going to leave them in the oarlocks, rotate them so they are lengthwise with the boat and lash them down to the top of the coamings.  They shouldn't be in the way.  I was considering some 7 ft oars that could fit in the cabin, but that's too short and retrieving them from the cabin would be annoying.

There are some equations for calculating the length of the oar based on the beam of the boat, but they suggested that I make 9.5 foot oars, which are too long to lash to the coamings while sailing.  8 ft is the longest practical length for this sailboat I think.  (I can also just barely fit 8 ft oars in my car, so that'll be convenient).

After doing some research online, I learned that store bought oars are not balanced correctly and too expensive.  I found some oar plans online by a guy called Culler.  His plans show oars with long narrow blades and are balanced for easy rowing.  Here are some links to the free plans I'm using:
www.riverswest.org/Pete_Culler_Oars.pdf
www.cmdboats.com/pdfs/Good_Oars_E-Book.pdf

The oars are laminated with 3 layers of 3/4" pieces of pine (one of the recommended varieties, others include spruce and doug fir).  I just cut the pattern from a 1x8.

An oar in pieces before lamination.
 Then I roughed up the surfaces to be glued with 50 grit sand paper, wet the surfaces with unthickened epoxy, then glued (with thickened epoxy) the 3 layers together.  I clamped the oar to the edge of the workbench, makings sure that the oar is straight while the glue cures.  The cheap wood I'm using was a little warped, but the oar should come out straight. I'm of course being careful to not glue the oar to the table.
An oar being laminated together.
 Next, I'm going to taper and shape the oars, removing any material that isn't an oar.  Shouldn't take too long.  That will be shown in "Oar Making - Part 2".

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