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Re: Scarfing with finger jointer--don't bother
By:Bill Hamm
Date: 2/19/2011, 5:09 pm
In Response To: Re: Scarfing with finger jointer--don't bother *PIC* (Paul G. Jacobson)

: Why do they have to be scarfed? Plenty of boats built with srips
: shorter than that--and those are just joined with square-cut
: ends (butt joints) located on any of the conveniently-spaced
: frames. You probably only need 5 to 7 full-length strips to
: start with, and then use shorter ones for the rest of the work.
: It is faster to do 5 scarfs by hand than to make a jig.

: If you don't open the stack and insert wax paper or something
: similar between each strip AFTER your cut then oozing glue will
: turn your pile of strips into a solid mass at the joint. You'll
: weaken the bonds trying to get your paired strips separated. If
: you insert the wax paper dividers, then you no longer have all
: the ends aligned, so gluing a bundle at one time means a few may
: be misaligned. You'll see large glue lines and gaps at the
: joints--and those joints will be weak. You will probably need
: more than one clamp. If you go this way do just 2 or 3 at a time
: and use 3 clamps plus some scrap on both sides of the stack to
: bridge the joint, and allow you to apply pressure without
: denting the strips.

: Biggest problems with fingerjoints are the time involved in making
: them, and the visual appearance of the strips. With an angled
: butt joint, a square cut butt joint, or a scarf joint there is
: just a single line. Usually this can be disguised. With a finger
: joint it looks like the boat was held together with zippers.
: With careful matching of strips this effect can be minimized,
: thogh.

: My favorite method. Rip, flip, cut the strip.

: Rip your original board in half (pretty close is good enough--you
: can be off 1/4" to 1/2" and this still works, but that
: would be pretty lazy) A 1x8 is 7.5" wide. figure 1/8th inch
: for the kerf of the saw blade and you want to cut 2 boards which
: are 3 11/16 wide, or a little under. If you set up to make the
: first cut a little under exactly a half, you can take your wider
: piece and run it through the saw to remove the excess and make
: it match.

: Flip one of the pieces so that the top half of that piece overlaps
: the top half of its mate. By mating the same ends of the
: original plank you stand the best chance of matching grain and
: color. Such matching helps disguise the joint. I use an overlap
: of 18" to 24", and clamp the boards together. Someone
: suggested taping the boards together, and I'll try that next
: time. I draw a diagonal line across the face of the boards in
: the overlapped area, and cut through them. Usually I use a jig
: saw, and dodge the clamps, but it is almost as fast to pick up a
: handsaw. The cedar is soft and it is easy to cut a straight line
: between the clamps. And if I wiggle a bit, it is no big deal.
: The top and bottom boards are cut like jigsaw puzzle pieces and
: even with wiggles they come together nicely.

: Some people plane these cuts before gluing. I don't. The rough edge
: of the cut holds lots of glue, the fit is always hidden.

: remove the clamps, set aside the cut off triangles (you can use
: them later for all kinds of stuff), apply glue to the freshly
: cut edges and join the two boards to make one long one. Use 2 or
: three clamps along the length of the joint, and don't squeeze
: them too tight. From two 8' boards you get a 14' board. Adding a
: third length give you a 20' strip. You lose 2' from every one of
: these long scarfs, but you get beautiful long strips.

: After the glue has hardened, use a scraper to remove the squeezeout
: from the flat sides of the board. That may work on the edges,
: too. Very light sanding by hand should make the area flat. Don't
: overdo it.

: If you want to remove knots from the board, use that cut-off piece
: as a gauge. set it next to the knot on your long board and trace
: a cutting line next to the knot. Cut on the line. Overlap the
: freshly cut pieces so the knot is on the bottom, and completely
: hidden by the top piece. If you are using a handsaw rest the
: side of the blade against the top piece as a guide, and cut
: through the bottom piece. if you are using electric saws, cut
: through both pieces, staying parallel to the angled cut, and
: about 1/4" inside of it. Glue and clamp. No more knot. Loss
: of a couple inches.

: When you rip your strips each cut will create a smooth and perfect
: section as it goes through the joint area. The ripping process
: automatically cleans things up. If you bead-and-cove the edges,
: rip a 3 degree bevel on the edges,or if you use a handplane to
: fit them individually, you'll remove any last traces of glue
: squeezeout from the edges. If you do nothing, then your scraping
: should have given you a smooth enough surface for gluing to
: another strip.

: Do this just once to get full length strips to start your sheer
: lines. It wstes a bit of material, but it is much faster,
: straighter and neater than scarfing individual strips. You'll
: get about 8 to 12 from the long, skinny board. After that use
: shorter strips. Once you set up your saw for ripping strips it
: doesn't matter too much what the length is. You'll need some
: help, or infeed/outfeed supports for the longer materials, but
: the strip thickness is already set on the saw.

: Here is an illustration of the rip and flip process.

: Hope this helps

: PGJ

I hate full length strips, pain in the butt to work with. I butt join them and much prefer having the joints fall between the forms, much easer to get them aligned if they don't fall on the forms. If I have one that falls on the form I'll cut it shorter so it doesn't.

Bill H.

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