Maximum Planking Width

[Ankle Deep]

I searched the forum for information on maximum recommended planking width. Per the discussions the primary concern with wider planks is the resulting gap between planks due to shrinkage associated with aging....correct? Also, it appears three inches and/or the max depth possible with a 10” table saw is the generally accepted standard for planking.

My question(s):

Is there a width that should not be exceeded? I will be re-sawing with a band saw and my available stock will allow me produce 4 inch planks for garboard planks and 3 ¾ inch planks for the remainder of the project. Are these acceptable widths? Are there other concerns with wider planks…i.e. other than the gaps produced through shrinkage?

Thanks in advance for the help.

 

[Just1moredave]

You can look up the species you have. For example, western red cedar:

https://www.wood-database.com/western-red-cedar/

The numbers you want are under Shrinkage. Radial is for quartersawn stock. Tangential is flatsawn. For a 3 3/4" quartersawn plank, they say 2.4% which is slightly less than 3/32". A 3" plank expands maybe 1/64" less. The planks will buckle if they try to expand without a sufficient gap between them.

You can also experiment. Make a sample plank and measure its width. Soak it for a while and measure again. I came up with pretty much the stated numbers. If your wood is not kiln dried or humidity is very high, you'll get less expansion.

The planks have to conform to the ribs so they have to curve across the width in some places. A wider plank might split.

My canoe had 3 3/4" planks originally, quartersawn down low and flatsawn close to the gunwales. I probably worried too much about gaps and not enough about color choice. When viewed from the inside, the gaps are not very obvious but some light planks look odd. I used a bandsaw for resawing. The hardest part was the smaller table on the bandsaw. My table saw has a 27" table plus 48" outfeed, great for an 8' board. A helper can be useful for the bandsaw.

 

[Dan Lindberg]

If you are restoring, match what you have, if building new, make it what's convenient for you.

As an example, Joe Seliga used 6" wide WRC planking for about 10 years when he could get it from a supplier that sawed & planed it for him, saving him some work.
it was layed tight and on my '58, it was still tight when I restored it.

Dan

 

[Dave Osborn]

I’ve had experience with wide flat sawn planking wanting to buckle or cup. A particularly bad one was a Chestnut Bobs Special that I restored for Kathryn Klos Campbell. I think the planks were about 5” wide and made with white cedar,...flat sawn. I’ve seen it to a lesser degree on other canoes as well.
Took a lot of wet towel time and additional tacks to get the cupping out.
I’d suggest, especially if your wood is flat sawn, to stay 3 3/4” or less.

 

[Dan Lindberg]

There's the magic words.
I replaced a bunch of planking on a Thompson years ago due to buckling, all flat sawn.


"flat sawn"

 

[Ankle Deep]

Thanks everyone for the helpful advice. I'm fortunate to have quarter sawn stock!