Scarf-joining strips

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Willy
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Scarf-joining strips

Post by Willy »

So I'm finally ready to start stripping the Merlin. I have ripped some nice strips and now I am trying to figure out the best way to glue my scarf joints. Today I used scrap strips on both sides like a splint with a clamp and then had some tear-out when I pulled them off. Any suggestions? Do you guys glue them up and let them dry before planing your bevels and fitting them up? I appreciate any suggestions.

Thanks,
Will
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gerald
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Re: Scarf-joining strips

Post by gerald »

Most of the time I'll simply use a butt joint on strips--especially on the hull. Those few times that I do scarf a strip--usually on a long sheer strip or the deck (rarely) I simply cut the scarf, apply glue, join them by hand, wipe off the excess glue, and clamp short pieces of strip on each side. It sticks a little but is easily popped off with no tear out. I do them as I need them.
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Pogo
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Re: Scarf-joining strips

Post by Pogo »

Pictures! We want pictures!

I've tried splinting them as you describe, and covered the scrap pieces with masking tape to act as release agent, but eventually quit doing it as too fussy a procedure that never worked all that well anyway. The photo below illustrates what I've settled into doing now:

At right, a fresh scarf is being clamped up with the spring clamp. I've used green tape on either side of the joint to act as clamps that pressure each strip end down against the previous strip course below, then the scarf itself is mashed together with a spring clamp. If any squeeze-out cements the springy-thingy to the boat, just give it a a bit of a whack to impart a spin motion on it; that'll usually break the bond cleanly.

I use a lot of green tape to help deliver even clamping pressure for each new strip I add, and prefer green tape over any other because it's strong, has just the right kind of sticky, and has the perfect amount of stretch. I learned to love it in a commercial cabinet shop where it's used for just about everything but making cornbread. Ask for "3M green lacquer tape", get it at paint stores.

Image

http://mysite.verizon.net/NGC704/newOI/page_2.htm" onclick="window.open(this.href);return false;
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gerald
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Re: Scarf-joining strips

Post by gerald »

That little plywood block with the groove cut in it is ingenious! I love it!
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Pogo
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Re: Scarf-joining strips

Post by Pogo »

Thanks, they come in very handy and I use 'em almost constantly. Easy to make, too; just set the fence on the table saw to 3" or 4" or whatever you want (mine are 4" square), and cut a stack out of ~1/4" plywood. Stack up the squares and sand all four edges; I leapfrog a couple spring clamps to maintain the stack while zapping 'em on the stationary belt sander. Drill a 3/8" hole in the center of the stack, draw a couple guidelines from the quadrants to the edge with a square, and cut the slot on the bandsaw. Sand the slot edges smooth, and you're in business. I can turn out a dozen in five or ten minutes.

The wedges are even easier, just make a Wedge-O-Matic jig for the table saw....

Image
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gerald
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Re: Scarf-joining strips

Post by gerald »

Thanks...I'll be making quite a few in the very near future. They'll go well with other little clamp jigs. I use the same method to make shims (wedges).
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Birke
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Re: Scarf-joining strips

Post by Birke »

I use a miniature miter box saw that I used when was making RC planes. Works like a charm.

http://www3.towerhobbies.com/cgi-bin/wt ... LXLH69&P=7" onclick="window.open(this.href);return false;
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gerald
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Re: Scarf-joining strips

Post by gerald »

As to how I do my scarfs in strips--I just clamp the two board together and use my longest 12 point handsaw (or backsaw) to cut the longest angle on the two strips that I can get. Toss the scrap ends and glue the joints....
Willy
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Re: Scarf-joining strips

Post by Willy »

Thanks for all the great ideas. Now I am thinking about using staples after all on this boat. Still not sure. I kind of think I am trying to bite off too many new skills at once to also try to go staple-less on my first boat. Any staples better than others. I have an electric stapler that worked on the first two strips but it has no adjustment for depth or power. Again, any ideas or suggestions are welcome.

Thanks,
Will
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gerald
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Re: Scarf-joining strips

Post by gerald »

I think it is a wise decision to use staples on your first boat. However--going stapleless means you have to make much better fits. Maybe on your second or third boat. I use standard 9/16" staples for for a T5 Arrow stapler...the hand squeeze kind. Since I am always investigating better and different methods I will eventually search for stainless steel staples and much thinner staples. Nothing is set in stone....
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Pogo
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Re: Scarf-joining strips

Post by Pogo »

Look closely at the business end of my pneumatic upholstery stapler, I've attached a stand-off spacer made of sheet brass that leaves a good 1/8" min. staple protruding. At its simplest, you can tape a piece of scrap wood or whatever under any stapler to achieve the same effect. It really protects the strips from dings and dents, highly recommended.

Image
http://mysite.verizon.net/NGC704/newOI/page_3.htm" onclick="window.open(this.href);return false;

I think it safest for beginners to use staples also, but then someone like my friend Tony comes along and breaks every "rule" in the book. He didn't buy plans, just used Schade's book; he didn't use staples, and he'd never built a boat before. He's built three now, and his building speed is right on up there. You just never know what any next guy can or can't handle....
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