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Re: Scarfing out knots
By:Paul G. Jacobson
Date: 2/21/2011, 3:21 am

: Just as an example, using an 8:1 scarf (about the minimum ratio for
: a reliable scarf) say you're using a 1x6, which is 3/4" x 5
: 1/2", you lose 6" of wood with a thickness scarf (8 x
: .75") or using a width scarf you lose 44" of wood (8 x
: 5.5"), I'd prefer using the extra 3' of wood.

Far better is to just work on a single strip after it has been ripped. Much less loss.

But, when I need clear wood for stringers for SOF boats, or the few clear, full-lenght strips, I'll take a hit on the length. Actually I lose about 18 to 24 inches. With a 1x6 I'll first rip it to half the width . (about 2.75") then join the two thin pieces to get roughly double the length. If there are knots near the ends of the boards I lose them when joining the thin boards. I try to avoid buying wood with massive knots in the middle.

Since my boards are just under 2.75" wide at this point, with an 8:1 scarf length I'd lose about 16 inches, plus the length of the knot. It is less than your forecast, but still pretty bad.

As for scarfing through the thickness of the wood, I'd need to set up a jig to cut the scarfs, and cut each board separately. I can just cut through half of a 1x6 on edge on a 10" table saw, but not half of a 1x8. I might do it on the bandsaw, though. Cutting in the other direction is fast--just stack 'em and zip through with a jig saw.

When the wood is cheap and time is expensive I go with the fast route. When the wood is expensive and the time is cheap, I'll cut the strips first, and then scarf them, or cut knots from them.

PGJ

Messages In This Thread

Strip: Scarffing with finger jointer
JohnK -- 2/18/2011, 7:43 pm
Re: Strip: Scarffing with finger jointer
Paul R -- 2/18/2011, 9:03 pm
Re: Strip: Scarffing with finger jointer
JohnK -- 2/19/2011, 8:05 pm
Re: Strip: Scarffing with finger jointer
Paul R -- 2/19/2011, 8:47 pm
Re: Scarfing with finger jointer--don't bother *PIC*
Paul G. Jacobson -- 2/19/2011, 1:00 pm
Re: Scarfing with finger jointer--don't bother
Michael -- 2/19/2011, 3:05 pm
Re: Scarfing with finger jointer--don't bother *PIC*
Paul G. Jacobson -- 2/20/2011, 5:52 am
Re: Scarfing with finger jointer--don't bother
Michael -- 2/20/2011, 11:09 am
Re: Scarfing with finger jointer--don't bother
Bill Hamm -- 2/19/2011, 5:09 pm
Re: Scarfing with finger jointer--don't bother *PIC*
Kurt Maurer -- 2/19/2011, 6:56 pm
Re: Scarfing with finger jointer--don't bother
Bill Hamm -- 2/21/2011, 12:55 am
Re: Scarfing with finger jointer--don't bother
Bill Hamm -- 2/21/2011, 1:13 am
Re: Scarfing out knots
Paul G. Jacobson -- 2/21/2011, 3:21 am
Re: Scarfing out knots
Etienne Muller - ireland -- 2/21/2011, 5:15 am
Re: Scarfing out knots
Bill Hamm -- 2/21/2011, 1:41 pm
OT: other type of scarf *PIC*
Paul G. Jacobson -- 2/21/2011, 3:31 pm
Re: OT: other type of scarf
Bill Hamm -- 2/22/2011, 1:42 am
Re: Scarfing out knots
Bill Hamm -- 2/21/2011, 1:40 pm
Re: Strip: Scarffing with finger jointer
JohnK -- 2/19/2011, 8:08 pm
Re: Strip: Scarffing with finger jointer
Paul G. Jacobson -- 2/20/2011, 4:58 am
Re: Strip: Scarffing with finger jointer
ancient kayaker -- 2/25/2011, 10:51 pm