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Re: Strip: splices
By:Paul G. Jacobson
Date: 1/15/2003, 6:16 pm
In Response To: Strip: splices (Russ Chambers)

: . . .almost all of my strips will meed to be spliced. I refuse to make
: butt splices and will do a 6:1 scarf splice. The question is, do I make a
: bunch of splices before running the strips through the B&C router set up
: or do I do the splicing on the forms while stripping?

There is no reason you can't follow both paths. In fact, I think you should.

Scarf together at least 5 long strips ( full-length of the boat) before you run them through the bead and cove operations. Use these first as you start stripping. Once you have them in place, the cove will help to align the adjacent strips as they are added.

If you cut your bead and cove first, and then try to line up the scarf joints, any slight misalignment of your strips will cause an irregular "bump" over the length of the scarf. If you scarf the long strips first then you get a smooth, continuous, cut from your router setup. Hopefully, no bumps or glitches.

You could do this for all your strips, but it takes more time and clamps to do all the scarfing first. That is why I scarf the boards before I cut my strips. (The time savings, and the straightness of the strips is much better, too.) Just do enough full-length strips to get started and then fit your joints as you apply shorter strips.

When you have a joint between two strips, the even cove in the strip they are being edge-glued to will provide some force to keep them in alignnment. You can increase this effect by spanning the joint on the other side with a strip (either a good one, or just a scrap) which is pressed into the cove side of the two strips which are being joined. In effect, you are clamping the ends of the strips being joined in a self-centering jig. If you use a scrap, wrap it with a single layer of saran wrap, so that it does not get glued permanently into place.

Of course your router setup for longer or shorter strips will be the same, assuming your infeed and outfeed areas can take the longest strips, and support them adequately.

Shorter strips are easier to store, and by doing your joint work as you go, you gain control over where those joints appear. This lets you use short sections of strips for best cost efficiency, or for decoration.

Now, my question for you is: Why a 1:6 scarf? I can understand it for the 5 or so full-length strips I suggest you make to get started - you'll need the strength of that bonding area to hold the long strips together - but when adding strips elsewhere it is not necessary. History has shown that butt joints (which alone have no strength to speak of) are strong enough for any boat when they are staggered and sandwiched between adjacent strips, so you are not gaining any needed strength with a 1:6 scarf. All you are getting is some cosmetic improvement -- which is a perfectly valid reason, and maybe the only valid reason.

You can get exactly the same cosmetic improvement by cutting the ends of the strips at a 45 degree angle (that would be 1:1 scarf). This also increases the bonding area over a simple butt joint, so the joint is a bit more than jsut cosmetic) A 45 degree angle can be accurately cut with a hand saw and miterbox, or power saw -- or you can remove the wood with a belt sander, disc sander, plane, or even a pocket knife. It is simpler,faster, and wastes less wood than a longer scarf. Since a 45 degree angle is so common it is easily repeatable without the need for special jigs. You can match one end cut on a saw with another shaped on a sander.

Just some thoughts. Hope this helps.

PGJ

Messages In This Thread

Strip: splices
Russ Chambers -- 1/15/2003, 1:07 am
Re: Strip: splices
Kyle T -- 1/16/2003, 8:48 am
Butt joint advantage
Jay Babina -- 1/16/2003, 12:33 pm
Re: Strip: splices
Paul G. Jacobson -- 1/15/2003, 6:16 pm
Re: Strip: splices
Steve Rasmussen -- 1/16/2003, 11:16 am
Re: Strip: splices *LINK* *Pic*
Steve Frederick -- 1/15/2003, 5:03 pm
Re: Strip: splices
Kurt Loup, Baton Rouge -- 1/16/2003, 8:40 am
Re: Strip: splices
Rob P -- 1/15/2003, 1:32 pm
Re: Strip: splices *Pic*
Jack Sanderson -- 1/15/2003, 9:59 am
Re: Strip: splices
Jay Babina -- 1/15/2003, 8:59 am
Re: Strip: splices
Kurt Loup, Baton Rouge -- 1/15/2003, 8:25 am
Re: Strip: splices,me too *NM*
Don Lucas -- 1/15/2003, 8:43 am
Re: Strip: splices
Jeff The Tall -- 1/15/2003, 1:29 am