WRC Board Estimate

[irose]

Newbie question and sanity check!

My canoe is going to be 15' and I'm trying to estimate how much timber to get.
I've measured the perimeter of the centre station and it comes out at approx 1400mm
So with 19mm strips I'd need about 74 (1400/19). I've rounded this up to 80.
I can get boards 150 x 23mm and I've estimated I can get approximately 18 strips per board.
So I've calculated 80 strips at 5 metres divided by 18 (strips per board) to give me metres needed of 150mm wide boards.
80*5/18=22.22 metres

Does this sound about right or have I made a mistake somewhere?

Thanks!

Ian

[Patricks Dad]

if your boards are 150 mm wide (that's 5.9 inches)... If your strips will be .25 thick (that's a pretty common thickness) and you use a 1/16" wide blade, you should get just 18 strips per board.. Any wider blade and you won't get that many strips. Any knots or waste, and you won't get that many strips... Buy a bit extra or choose your lumber very carefully. (you rounded up only 1/3 of a board)

Also, if you are going to bead/cove your strips, be sure to account for that in your final strip width (23 mm to 19mm seems close)

Determine how long the boards are you are buying before you finalize your calculation. If you can find full length boards, you won't have to do any joints. If your are using shorter boards, you will need to join them mid-strip.

Note also that as you strip up the hull, the length of your strips will get shorter so you will probably be fine. It's always good to have extra particularly if you are book matching strips side to side (you don't want to get down to the last few strips and find they aren't the right shade of wood for your pattern. Also, any extra strips you end up with can be used on your next boat (you can't just build one) or for a paddle or two.

Enjoy your build.

[Cruiser]

Short story ... I ran your measurements through my spreadsheet and you are in the right ball park, on the higher side I think.

When cutting the strips try and get a thin kerf blade (24tooth, demo Freud works perfect) for a skilsaw, they are about as thin as you can get ... thin translates to easier cut and minimum waste. With this I calculated ~20 strips/brd.

Your 19 mm is basically 3/4", so for planning you use 5/8", because the cove and bead (assuming you use those, I would) will cost 1/8" (the way they fit into each other).

So plan 16' per strip run, will be 15+ whatever curve adds (your 5 m is ~16.25", so that is plenty), so I just plan at 1 foot longer. Your 1400 mm perimeter should be divided by ~16 mm to account for the bead and cove (assuming you use them), so that is about 87 strips. You will have losses and the strip length required gets shorter as the build proceeds, so this is a fine working number and will likely result in some leftover, which is a good idea.

We differ a bit on the final figure, but a) taking into account the narrower strip width due to B&C b) using the thin kerf blade to maximize strips/board ... goes from 18 to 20 / board ... the number comes out right about 22 M, so you have the right of it as far as I can tell.

Brian

[Patricks Dad]

Brian,

It seems he's starting with 23 mm thick boards. The bead and cove will take him to about 19.

[irose]

Thanks for the replies and advice!

Yes, I am starting with 23mm and estimated 19mm after b&c. I'll be using the 24t Freud as well.

I've built my strongback and I'm just about to start cutting my molds.

Looking forward to this

Ian

[Cruiser]

I live in Canada and it gets confusing ... our wood is technically in metric, but it is usually sold as imperial ... I guess I lost the detail, so I stand corrected

[Jim Dodd]

Ian

My advice is to cut plenty of extra.

As you sort through color variations or just strip quality, you will find some don't measure up to standard.

Increase your odds by cutting extra strips !

Jim