Sweep Oar info

[BillyBudd]

Recently I've seen sweep oars mentioned in WBmag and the Small Boat mag too. I'd be inclined to make one/use one, but would like some info on shaft joinery, etc. Because of cuddy size I would need a 2 piece oar, so a joint is called for -- how to make, how to row/sweep to protect the joint?? Also, for a 20' x 8' boat (Bolger's Chebacco), does anyone have thoughts on shaft diameter, blade dimensions that will be effective? (BTW, especially liked the photos of the cabin storage of the sweep oar in WBmag's article by Dillon on "Tern.")

[Dana Marlin]

I plan to have a sweep on my 18ft cutter. I have made it one piece at about 10ft and will have it housed along a shroud. You only need one oar and a tiller - that is how the Pardey's manovered their 22 footer and they sailed around the world for many years...

[Wooden Boat Fittings]

.
Sanderling was my 20' YM 3-Tonner. She had a single sweep 14' long, cut down from an 18' life-boat oar. It was kept in chocks on deck, although I confess it was a bit of a nuisance there. It could be used for rowing (standing, facing forward) from either side of the cockpit, or by sculling over the stern. Shaft diameter was about 2½" from memory, with a smaller-diameter grip about 9" long.

Mike

[Thorne]

I'm certainly no NA and not much of an oar-builder (only made one pair and restored several others), but don't they need to flex relatively evenly?

I have had other spars like masts and bowsprits break where attached or sleeved for extensions, and assume that would also be the case for a long oar used for heavy work.

So if you need to use a 2-part sweep, consider a sleeve of semi-flexible material like carbon fiber or ??

Not to spout heresy here, but have you considered picking up an old 10'+ racing scull sweep? The carbon fiber material won't mind being lashed to a shroud semi-permanently and the cost would be minimal if you can find an old oar.

[Brian Palmer]

I have a 13 foot sweep for our 20 foot, 1200 lb (empty) Elver canoe yawl. The shaft diameter is 2 1/4 inches at the greatest point. I initially made the loom near the blade too small in diameter, so I had to build it back up with pieces laminated on either side (I'll measure the final when I get home). Even after beefing it up, it still flexes quite a bit when in use.

The loom just above the blade is 1 3/4 x 1 1/2 inches.

I can store ours either on the side deck or inside the cabin. When in the cabin, it comes out into the cockpit but lies along the edge of the cockpit seats so it is not in the way.

A two piece oar in that size could be a problem. The lever fulcrum is pretty close to where the joint would be. I am sure it could be done, though.

As an aside, two piece oars are not like two piece kayak paddles. In a kayak paddle, the fulcrum is the hand closest to the water, and the joint is well away from that point. The stresses on a kayak paddle are also a lot smaller than the stresses on a sweep oar used on a 1200 lb boat.

Brian

[Russ Manheimer]

Here's my lash-up on Sjogin. The oar is about 12' long and came with the boat. I expect it's an old life boat oar and made of ash. With vigor, I can get Sjogin up to a couple of knots. Fortunately there's usually a breeze coming off or going to the ocean.

[BillyBudd]

Hoping that someone with experience with sweep oars will offer comments on best place/best practice for a joint in the shaft/loom. Seems the entire length will be stressed, so a ferrule of sorts, a lengthy s/s pipe or rod insert might be proven effective.

[Brian Palmer]

Hoping that someone with experience with sweep oars will offer comments on best place/best practice for a joint in the shaft/loom. Seems the entire length will be stressed, so a ferrule of sorts, a lengthy s/s pipe or rod insert might be proven effective.

I think a ferrule system is the best option. A rod won't really keep the shaft from flexing since the rod would be on the neutral axis of the oar.

Brian

[Gerarddm]

I seem to remember that in the East they used to have intentionally hinged sweeps? Supposedly very efficient. I wish I could recall where I saw a photo or explanation...

[Jamie O]

Recently I've seen sweep oars mentioned in WBmag and the Small Boat mag too. I'd be inclined to make one/use one, but would like some info on shaft joinery, etc. Because of cuddy size I would need a 2 piece oar, so a joint is called for -- how to make, how to row/sweep to protect the joint?? Also, for a 20' x 8' boat (Bolger's Chebacco), does anyone have thoughts on shaft diameter, blade dimensions that will be effective? (BTW, especially liked the photos of the cabin storage of the sweep oar in WBmag's article by Dillon on "Tern.")

I made 12 footers for my Chebacco for the first Shipyard Raidm, we did a lot of rowing that year.. I put the oarlocks just outside the coamings and the length was just right for a rowing seat about 8" higher than the standard cockpit seats. I used a box on top of a board between the seats. (I have rails just below the cockpit seat tops so the floorboards can be mounted level with the seats for sleeping.)

I wrote an article for Duckworks about making the oars, see http://www.duckworksmagazine.com/06/...oars/index.htm
for a hand-drawn plan showing the dimensions I used. I'm happy with the oars, but a boat the size of a Chebacco is a b*tch to row for 8 hours!

Jamie

[Bill7254]

Duckworks sells a gadget that attaches a handle to an oar to make a sculling oar.




Has anyone tried this?

[wizbang 13]

I watched the video of that "scullmatix". It looks lame. The guy is making a knot in a dead calm and still wagging around. Anyone who can scull could pull it in circles. (Or straight if thats what you want)

[BillyBudd]

Here's the info that Harry Bryan supplied to me, based on his sweep oar for his own design and boat, "Katie". "Katie" is 20'x7' and weighs 2400 lbs. which is twice the weight of my Bolger Chebacco.

I have a tremendous respect for Harry. Imagine this: When I called him this morning, the sound of a hand powered saw was in the background (rrrr, rrrr)...not a power saw (@%$^&#%$!). An article on "Katie" is in the current Small Boats magazine.

What I learned...so far: 10' oar with a scarf joint mid-way, scarfs to be with about 1/4" nibs that notch into the other (fairly typical scarf to be found, say in Chapelle's book on boatbuilding). He has a brass band going almost about each of the scarfs, and a 1/4" carriage bolt that fixes the assembly together. The idea springs from a detail found in Maynard Bray's book on Mystic Seaport Museum's watercraft, a dinghy's mast (2 parts) designed by LFFH. I'll look up the book, the detail, and work it out. Standard size loom, oarlock.

Oar blade has a ~4" sweep to it. Harry likes to scull with it and his "Katie" has a sculling notch in her transom. For my boat, most likely I'll set up a bronze oarlock holder on one side of the transom and start studying how to sing Puccini opera. Should get me in/out of the mooring field without resorting to the outboard.

[Jay Greer]

I use a twelve foot sweep to power "Red Witch" through calms. The Witch weighs ten thousand pounds but, is easy to scull once she is moving. I store the oar in slings on the life lines. It was a stock oar that I purchased from a dealer as I had plenty of other work to do at the time I needed it. Personaly, I think that a two piece Yahloh would be a better choice since they are made that way and each stroke is a power stroke.
Jay

[pwilling]

Do a search for "yuloh", the Chinese answer -- usually two or three piece by design, perhaps you could adapt the whipping to your needs. See Worcester, Junks and Sampans of the Yangtze.

[keyhavenpotterer]

Yrvind, is building a Matt Layden inspired long distance cruiser. Here are his thoughts on his yuloh design



http://www.yrvind.com/2010_01_01_archive.html

Brian

[wizbang 13]

yuloh that I know has 2 strings