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saltytheseadog
10-29-2005, 03:26 PM
Hi folks, getting different feedback on whether planking should be slash cut or quarter sawn.

Bob Cleek
10-29-2005, 06:35 PM
Depends on the construction method. Clinker built (lapstrake) is slash cut. Carvel is quartersawn.

Stiletto
10-29-2005, 06:40 PM
One boat builder I spoke to avoided quarter sawn in that application. His reasoning was that it was easier for fastenings to split the planks, and that the stability gains were less important in a timber that remained damp.

Bruce Hooke
10-29-2005, 06:45 PM
I wonder if it does not also depend on the wood used. Some woods shrink and swell at pretty similar rates in both directions and others do not. Some woods split easily and others are very hard to split and in some the ease of splitting the wood varies a lot based on grain orientation and in others grain orientation does not matter much at all. This may be why it is hard to get agreement on the question...

Bruce Hooke
10-29-2005, 06:48 PM
Originally posted by Stiletto:
One boat builder I spoke to avoided quarter sawn in that application. His reasoning was that it was easier for fastenings to split the planks, and that the stability gains were less important in a timber that remained damp.Another two variables may be the local climate and the local practice in terms of off-season storage. In a relatively cool, damp climate where in-water, off-season storage is common, stability is going to be much less of an issue than in a drier climate or a place where extended out of the water storage in the off-season is the norm.

Ralphw
10-29-2005, 06:54 PM
what Bob said smile.gif

Bob Smalser
10-29-2005, 06:59 PM
I think you'll find that any given log produces a third+ more good planks when set up for riftsawing as opposed to q-sawing....so boards with some grain angle in them will be more common and less expensive:

http://www.woodcentral.com/articles/images/291x.jpg

http://www.woodcentral.com/cg i-bin/readarticle.pl?dir=smalser&file=articles_291.shtml (http://www.woodcentral.com/cgi-bin/readarticle.pl?dir=smalser&file=articles_291.shtml)

Accordingly, even tho I grow my own, I use riftsawn almost exclusively simply because it's the best value. I don't much care what the boat is. Both boards move seasonally....and both boards can split with improper fastening. Any differences in those is largely moot in application, although I favor riftsawn for peace of mind in fastening....and all those closely-spaced clinker rivets require some peace of mind, given the difficulty of fixing a split.

http://pic3.picturetrail.com/VOL12/1104763/6791366/85653808.jpg

[ 10-29-2005, 08:03 PM: Message edited by: Bob Smalser ]

George Roberts
10-30-2005, 11:40 AM
saltytheseadog ---

It all depends on how skilled you are.

Most wood species have a preferred splitting directions. It is best to use woods where the preffered splitting direction is not loaded.

Bob Cleek
10-30-2005, 01:27 PM
Thanks for that great post, Bob! The information on the Lucas mill was really interesting. I've used the Granberg mill once with somebody who knew what he was doing... on oak, and I agree, I'd hate to have to use a chainsaw mill to get out plank stock. BTW, the stuff you put out continues to amaze me. I don't know how you get so much done and still have time to document it so well! Thanks again!

Jay Greer
10-30-2005, 02:34 PM
For hulls that have a lot of shape and planks that will have a lot of twist, I prefer rift sawn stock. One must take care to note which way the planking will cup in relation the the anular rings. This also reduces tendencies towards splitting.

saltytheseadog
10-30-2005, 10:33 PM
Thanks all . I can see there are too many variables to form a clear consensus on how a plank should be milled.Some of your insights will guide me in my choice of planking stock.