Plank width Max. or Min.

[DN 5449]

What is your thoughts, go max. width 7.5" or min. 7".Advantages and disadvantages of each?

[DN 5449]

Here is my thinking I have 6 really nice strips of clear  Black Ash ,if I use three for the top and three for the bottom skins it will give me a Plank of 7 and 1/8".Conversly I can add 3/8" strips to the ends to bring it up to Max.width.

[Bob Gray]

  The only advantage to a narrow plank is that it weighs less. The wider the plank the less likely it will twist while sailing.  I'm not familiar with black ash, white ash is by far the preferred wood for the outer skins.

[DN 5449]

White Ash is predominatly found in Eastern Ontario.Here in North Western Ontario Black Ash is predominant.Both have very similar characteristics.In fact I was told that most boat builders prefer the Black Ash to White ash for bending and strength properties.

[DN 5449]

Further research indicates Black Ash is not as strong as White Ash, the only good news is it is lighter and Splinters less.Kind of puts me in a further predicament as I now have 8 strips of Black Ash cut up planned and ready to be glued.I am thinking of fiberglassing so that might make up for some of the loss of strength.Either that or my door frames are all going to be converted to Black Ash trim.

[Bob Rast DN1313]

I didnt see you mention a core usualy you can use spruce or  cedar or something softer for core and ash on outside top and bottom. Depending on your weight the width might not matter.
you could add short pieces at chocks to make wider in chock area.

If your lighter 150 to 160 lbs you could try a hollow  semi hollow plank.
for core use strips on each side , solid area under chocks, and stud plates and zig zag some diagonals
between plate blocking and chock blocking.
I built one like this years ago and still going .had to ad some glass as it was soft but reall comfortable when sailing.
Have to watch min weight spec I believe 25lbs with hardware.
Current deflection numbers Ive used is about 1 5/8" to 1 3/4" with just your weight on plank

Bob Rast DN1313

[DN 5449]

I am 160 lbs and have made up a cedar core.After reading an earlier post on DN archives,I am thinking of going with a combination of Birch and Black Ash strips.

[Bob Gray]

  I presently sail a wing shaped hollow plank and have had several standard hollow planks in the past. They work great in the vertical/spring mode but they are not as strong in other planes such as when hitting something straight on or even hitting a crack just right. I've blown up two hollow planks in such events.. The core material acts more as a spacer then adding terribly much to a planks stiffness ( this statement is somewhat simplified). In the fore and aft axis the core contributes as almost as much as the skins considering the wood itself is generally less stiff. I personally like sitka or basswood for a core more the weaker woods like cedar and even redwood (cedar and redwood are prone to long grain splitting).