The design of these oars is based on a very old but elegant pair of
sculls which were among the collection of the Dolphin Boat Club of San Francisco. The original pair were
almost certainly made in the
Bay Area sometime before World War I-perhaps by Al
Rogers, oar and shell builder from Oakland, California, whose advertising slogan at the time was "Spoon Oars and Fast Boats."
For anyone wanting to build sculling oars, this design is one of very few ever published, and is probably the most detailed. The blade shape is much more like a traditional pencil blade popular until the early 1960s than the more modern Macon blade, but will be quite adequate and satisfying to propel a traditional wooden racing shell or wherry.
has actually put the considerable labor
and material cost into making a pair of sculling oars, will quickly realize
why the high cost of a good pair of used sculling oars may be quite the bargain.
Please send us pictures/descriptions of your self-made oars!
They will be published here.
Quality oars such as these are hollowed out inside to lighten the outboard end. This means that you are lifting less weight with each stroke.
The semicircular groove is 3/4 inch wide at station P. It runs from a depth of 3/8 inch near the button and fades out to zero at station 1. The limits of this groove are shown on the drawing that follows. You'll need a 3/4 inch core bit, preferably carbide tipped. It's best to make a tapered jig for this grooving operation, although with a bit of care you could do it with a plunge router equipped with a sturdy fence. Practice on a piece of matching scrap until you are quite confident.
When the hollows are cut, glue up the two halves with epoxy resin glue. Make sure you mark them in some way so you'll know
which end conceals the hollow.
Now create the two 2 1/2 inch-wide blocks - the "wings" of the blade by glueing several wood strips together. It is important to have the grain fibers all sloping the same way. If you don't do this, you'll find yourself working a tangle of grain with a tendency to tear up, whichever way you plane it.
Next make two full-sized templates of the blade from station 0 to station 1. You need one in profile (pattern X), and another in plan view (pattern Y).
These are both shown full-size below. Although the whole width of the blade is drawn, you'll find it more convenient
to make a half-pattern. Plexiglass, 1/8 inch or 3/16 inch, is ideal for these patterns because you can see the grain configuration, as weIl as pencil marks, through it. However, if you are just making one pair, thin plywood such as the kind sold as "doorskins" works almost as well.
Transfer the patterns by laying the drawing over the pattern stock and pricking the lines through with an awl sharpened to a needle
point. Transfer the grid lines at the same time and label each one 0 through 1.
Cut the patterns out and smooth the edges.
Draw the profile (pattern X) first. Transfer the grid lines at the same time and label each line 0 through 1. Do the same with the other oar, and then bandsaw just dear of the lines on the concave side only. Leave the back of the oar blade flat along its entire length; this gives you a valuable reference and is more amenable to being held in a vise when shaping the inside of the blade.
Next find the center glueline and spring a thin steel ruler down onto the face and darken the line with a pencil. Square your grid lines across the newly sawn face. Also establish the center-line and extend the grid up the whole length of the oar to station W. After station H, grid lines are placed every 6 inches instead of every 3 inches because the sections are changing less drastically.
Now spring the half pattern (Y) down onto the inside of the blade so the straight edge coincides exactly with the centerline. Slide the pattern one way or the other until station D, on the pattern, lines up with station D on the oar. This minimizes the slight distortion caused by springing a flat pattern down onto a curved surface. Mark the curve with a pencil, flip the pattern about the centerline, and mark the other half of the blade.
Starting at J, mark the widths of the loom at every station, both sides of the centerline. Since you do not have a full size drawing of this part of the oar, use the half sections instead. Tack a faring batten at each station so as to join these points in a smooth curve, and mark with a pencil.
Bandsaw just clear of the pencil lines and cut out the whole outline of the oar blade and loom. Don't cut to the finished length yet. If you leave a couple of inches of the loom projecting beyond the end of the blade, it's convenient for clamping.
edges you have just sawn until they are smooth and fair.
Run your grid line down both edges at each station. Otherwise, you will lose them in the next step - planing the upper surface - and have to start over. Use the full-sized sections below once more to lay off elevations at all stations along the loom, both sides, as seen in profile. Fair these points with a batten and mark.
Do the same for the blade of the oar.
Use battens to
draw fair curves through the connecting elevations of both spine and blade edges as weIl as the blank backside.
Note that the blade actually has three profile lines:
If you don't plan to use copper oar tips, epoxy oak or mahogany blocks across the grain of the blade as shown in the drawing.
Make up some full-sized templates - from cardboard or plexiglass - to give you the exact profile of the inner surface of the whole blade from station A to station H.
Now use a spokeshave to plane down to the lines drawn on the blade's edge: top of blade edges to E, then top of spine center to H.
Now with a compass plane and gouge, fair in the centerline of the blade. This dips below the elevations of the top edges at station E, but rises above them from E to H. At station 0 all three are in the same plane. It's best to get a gouge with a profile closely matching the curve along both sides of the center spine.
Start with the blade
template for Hand worktoward the end of the blade. Do this station by station, until the ends of the template
touch the pencil line at the blade perimeter and the center fits the shape and touches the line down the center of the blade. This is at finish elevation and fair.
Sand with 60-grit and an appropriately rounded block for a smooth, fair surface.
First make a plexiglass, thin plywood, or card-board template for each of the full-sized sections I through W.
Now set a pencil compass to the half-width of the flat side at each station. Lay these points out on the loom, then connect them with a fair line by means of a batten. Plane the curves down to the line but don't plane them out or you'Il lose an essential reference.
Do the flat side first, then turn the lomm over and plane the top side. It's best to use a low-angle block plane on the flat side because there's so little wood to remove. A jack plane works better for the upper side.
Finish with a spokeshave and plane to fit the templates at each section. Set an outside caliper for finish width while working up each station, and dont reduce the sections beyond it. Work from the thicker section in long strokes with arms fully extended.
Sand down when fair to all section shapes.
Bandsaw just clear of the lines you marked previously on both edges.
Take a low-angle block plane and plane down flat across the width of the blade to the pencilline. This will project the bottom curve from the outside edges to the centerline of the blade.
Now shape the back of the blade with a spokeshave while rnaintaining a uniform thickness of 3/8 inch along both blade edges.
You may want to make a
couple of circle templates which you can slip over the handle to check progress.
At this point you can cut off the excess at the handle end and shape the handle to a smooth cylinder, as shown below, with a rasp.
The final step is to sand the loom with 80-grit and a sanding block.
Check for fairness by eye and then, if necessary, use a sharp, lew-angle block plane, set very fine, to take down any high
spots. Fair in the curves, sand again, and eyeball.
For a final sanding, fold a sheet of sandpaper in thirds, the long way, and use a flat block of wood, the same length, as an aid to achieving a fair surface. Block-sand and hand-sand at 35 degrees diagonally to length of loom when sanding off the horizontal.
First of all: Patience and endurance
To build these oars requires about 60 to 70 hours of work. If this is your first time build, it can last double the time.
Good woodworking skills are a must.
You can build your oars in a dry place outside of the house. But at winter time or in case of wet/bad weather a covered, warm place witht a size of about 2 x 5 Meters is way better for doing it.
There are only a few simple tools required for the build:
Wood - Spruce is recommended
Ask a carpenter for fine grain, knot free strips
Epoxy, Glass Webbing, Boat Varnish
Suter Kunststoffe AG, Aefligenstrasse 3, CH-3312 Fraubrunnen, Schweiz
If you run into problems and want to ask for help:
Ask me, I'll help you, Ruedi Anneler, Büren an der Aare
It is not free!
CHF 35.- per working hour