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View Full Version : An explanation for a novice. Wood grain and oars.



Trebuchet
07-21-2008, 10:01 PM
Hello everyone. I've been reading the forum for a while, and reading WoodenBoat for years. I've recently embarked on my first boat, and I'm starting to put together some oars for her. I was reading up, and have come to something where I'm really out of my element. I picked up this 8/4 Ash this afternoon, and just want to make sure I'm understanding what I'm reading.


Here is the only tricky part: the grain of the oar piece must lie so that the grain runs in the same direction as the length of the boat. When you apply pressure, you do not want that pressure applied on the flat grain. The flat grain, in other words, will lie against the gunnel. Glue your short pieces so that the pieces are glued to the flat grain of the oar [the long piece].

http://img.photobucket.com/albums/v293/suntzu_2002/IMG_2446-1.jpg

This is the boat so far... next step is to glass the chines.

http://img.photobucket.com/albums/v293/suntzu_2002/IMG_2440.jpg

Thanks for the help everyone, and keep up the great work.

Bob Smalser
07-21-2008, 10:44 PM
Think baseball using wooden bats. You're told never to hit the ball on the label because the bat's label is always stamped on the bat's flat grain. The intent is when the ball makes contact, it makes contact with the vertical grain side of the bat. Ash splits easily along its growth rings.....hitting the ball in the flatsawn side is guaranteed to break it, just like your source believes the pressure of the oarlock on the flatsawn side will eventually break the oar.

But it takes a bigger tree than most of today's ash to provide the 6-8" vertical grain stock needed for marketability. So most ash stock is flatsawn, and most ash oars are also flatsawn to no ill effect. Moreover, some oars are purposely made with flatsawn stock so they have more spring during rowing. For your purpose in a light skiff, I doubt that any of this matters. To make oars with VG looms from your flatsawn stock, rip your stock into thirds with the center section square in cross section, then glue it back together with the VG of the center section facing outward. Like this:

http://pic20.picturetrail.com/VOL12/1104763/7081299/91841741.jpg

That said, ash oars are most appropriate for lifeboats and heavily-loaded fishing or work boats. They are unnecessarily heavy for a small, light plywood skiff. If you can, you'll be happier trading it in for Basswood, spruce or Douglas Fir. Basswood is especially easy to work and is underrated as well as inexpensive.

A Simple Pair of Seven-foot Oars (http://www.woodenboatvb.com/vbulletin/upload/showthread.php?t=3422&highlight=Simple+Pair+Seven-foot+Oars)

PS. And for reference, this is what VG stock looks like....

http://pic20.picturetrail.com/VOL12/1104763/4518261/56509965.jpg

...and don't forget to check for and correct any grain runout along the length of your stock:

http://pic20.picturetrail.com/VOL12/1104763/4518261/56509953.jpg

Trebuchet
07-22-2008, 07:39 PM
Thank you very much Bob, that was very informative. I went to the lumberyard planning to get spruce, but I didn't see any that was suitable. He did however have this ash at a good price, so I took it instead.

Peter Eikenberry
07-22-2008, 08:10 PM
This is off subject but that boat looks like an FL12 from Bateau.com. I just built one. Is that what this is, and how did it go?

Andrew Craig-Bennett
07-22-2008, 08:53 PM
Bob is right, but since you have the ash, you can make nice oars from it. They can be smaller in section than softwood oars, since ash is very tough stuff.

In order to compensate for the extra weight, use the Pete Culler trick of drilling an inch hole maybe three inches deep along the length of the oar in the ends of the handles and fill the hole with a slug of lead (no need to melt it, rolled sheet is fine) then glue a plug maybe an inch deep into the end over the lead. This improves the balance of the oar, as does keeping the inboard part of the looms from the leathers up to the handles square.

Trebuchet
07-22-2008, 09:02 PM
Peter, it is an FL12. The picture I posted is how far along I am at the moment. Just planning ahead to have the oars ready when the boat is. I need to fiberglass the chines, fair, and paint. What is it... 90% done, 90% to go.

Thanks for the suggestion Andrew, I had read about the lead in the handle trick, and had planned on doing just that.

Bob Smalser
07-22-2008, 09:27 PM
Of all the reasons I don't recommend ash as a first oar, weight is the smaller of them, as shaping oars is done with hand tools

Kiln-dried ash is very hard, but with inconsistent texture between the earlywood and latewood of the growth rings. You'll need sharper tools than most beginners use and the experience necessary to make shallow, consistent cuts that don't dig deeper into the earlywood and subsequently take a hunk out of the latewood during the cut. When the cutting tool chatters stop work, resharpen it and try again at a finer setting. When it digs, pay more attention to your weight transfer on the tool during the cut.

Kilned Doug Fir and spruce have similar problems, but are much softer and more forgiving. Basswood OTOH is an even softer wood with such a remarkably even texture the end result will be a pleasant surprise.

It's also a much better choice than advertised. I have basswood oars on work boats that have been in unprotected outdoor service getting baked in the sun and rained/snowed on for over 10 years.

http://pic20.picturetrail.com/VOL12/1104763/9745605/138775367.jpg