Board length calculation confusion

Submitted by dkavran on Fri, 07/19/2019 - 14:11

Hi All,

i am ready to begin ripping strips for my petrel play and am confused with the materials calculator provided on this site.  Under the field where it had you enter the strip width I am not sure what value to use.  Nick says the strip width is also the width of the board, so would I enter 1.5 given I am starting with 2x10 stock, or do I enter .75 given that will be the width that I will rip the strips down to?

any help would be greatly appreciated.

 Thanks!

Dennis K - 

JohnAbercrombie

Fri, 07/19/2019 - 16:00

Dennis-

One thing to keep in mind is that you won't get .75 wide strips by ripping 1.5 strips lengthwise, because of the loss to sawdust (blade kerf).

Starting with 2x10 lumber there are a few different options for milling lumber - this can depend on the grain appearance you want on the kayak surface. For example, you could rip .75 x 1.5 strips from your 2x10 and then cut .75 strips from those sticks.

 

BTW, Nick says that the board thickness is the strip width. The calculator assumes you are ripping the strips in the simplest way, as shown in Nick's book and also in Ted Moores Kayakcraft.

A narrow kerf blade makes a big difference in your yield. 

Also, please set up a safe outfeed table and ripping guide I think Etienne Muller has details on his website; he's posted them here in the past, IIRC.

Thanks!

My plan is to first cut .75 by 1.5 planks from the 2x10 and the cut the 3/16 strips from this - as I saw Nick do on the web series outlining his build of the petrel play - I am still confused though as to how to figure the amount of board length I will need

JohnAbercrombie

Fri, 07/19/2019 - 17:41

You need to add the info for kerf and surface area of boat....

 

wood calculation

BTW, many builders rip lots of extra strips and use that as an excuse for starting another boat after the first one is completed!

:)

dkavran

Mon, 07/22/2019 - 22:16

In reply to by JohnAbercrombie

Before I buy my cedar lumber I have one final question - i have seen is many videos that builders start with a 2x10, or something similar, rip 3/4 inch planks, flip it on its side and then rip the 3/16 strips.  Is it possible to simple start with a 1x10 and rip the 3/16 strips right off the edge ?

any feedback would be appreciated 

thanks!

Dennis

 

JohnAbercrombie

Tue, 07/23/2019 - 00:52

It's certainly possible to rip strips from the edge of a board.

If you buy flat-sawn boards, ripping from the edge will give strips with parallel grain lines showing on the boat surface, which many builders prefer.

Repeating myself here: taking the time to set up a good outfeed table and ripping fence/guide will pay dividends in the uniformity of your ripped strips.

JohnAbercrombie

Tue, 07/23/2019 - 00:55

Sawing wider (1.5") strips from a 2x board and ripping them into two, lengthwise will also work.

If you do that, setting the blade at an angle of 5 degrees or so (??) when splitting the strips can save some work in fitting adjacent strips to the forms.

John, you said, "setting the blade at an angle of 5 degrees or so (??) when splitting the strips can save some work in fitting adjacent strips to the forms." Great time saving idea. With careful thought it should be easy to figure out how many board lengths would be needed for this cut

Smilin'Andy

Mon, 11/25/2019 - 13:04

In reply to by JohnAbercrombie

IIRC Rob Macks at Lauging Loon says on his site that he rips a 3 degree bevel on one side of his strips.

I'm still probably a few months away from making sawdust on my first boat, but I'm leaning toward leaving the strips square and using Nick's Robo-Bevel and block plane methods.