# scarf joint jig



## bearclaw (Nov 2, 2011)

I am making the gunwales for a cedarstrip canoe. They are to be 3/4" by 7/8" by 16' long. I have 12' stock. I want to make a scarf joint 1:12 ratio. Does anyone have a jig or preferred method to cut these angles. Repeatability is a problem. 

thanks bearclaw


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## LexB (Apr 12, 2010)

In a couple of weeks I'm going to start building my first "stripper" too, but mine will be a kayak. A lot of builders make a jig for the tablesaw, but I think that I'm going to build one to use a router instead. My idea is similar to the jigs for using a router to surface plane large slabs, but the main difference (other than size) will be that the stock will be held at an angle to the router base (for the 1:8 or 1:12 slope). I'll use a down-shear mortising bit to get a smooth surface for a stronger glue joint. Some builders scarf across the width of the strip, and others across the thickness. I prefer the appearance of scarfing across the thickness, so that's how I'll build my jig. I haven't worked anything out in detail yet, but when I do I'll post the Sketchup model here. My idea is similar to this one, but not as wide because I'll be scarfing thin strips not wide planks.


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## JCJCJC (May 15, 2012)

There's a jig here that might be a help to you, even if it's not a router jig.

talkbassDOTcom/forum/f57/scarf-joint-jigs-501205/#post6742621

If you search around guitar-building forums you'll get a lot of ideas because the neck-to-head joint, where there is one, is usually a scarf joint and some guys have come up with clever ideas for making good ones.


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## Harrison67 (May 30, 2012)

Steve's Guitar Making - Part 2 - Neck session 1 of 4 - YouTube


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## damnitboy (Mar 3, 2012)

Howdy Lex,
Woodhaven makes a fixture for making scarf joints that works very well. Thak a look.

Woodhaven 3400 Scarfing Sled : Scarfing Sled


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## JOAT (Apr 9, 2010)

Just do a search. Use something like 'how to make a scarf joint jig' for your search phrase. That turned up a ton of info, plans, and how tos.


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## rwl7532 (Sep 8, 2011)

Another example:
How It's Made Drum Shells - YouTube
at 1:14 is where the action starts.


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## routerworks (Feb 20, 2012)

Barry, when I made my gunwales, I took a small section of 3/4 x 7/8 stock and drew a diagonal line 9" from one side to the other which is the 3/4" x 12 scarf. I brought this to my table saw and clamped it to the miter and cut it until I came to a cut parallel to my line. This meant modifying my miter with a jig since it wont go to this angle. Once I made the jig I just clamped my longer stock which had the other end supported on a table and cut my scarf. It worked fine.
Fred


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## bearclaw (Nov 2, 2011)

Thanks. The only problems with guitar jigs is that they are using short stock. I am trying to scarf a 5foot piece onto a 12 foot piece and their jigs are too short. Still I might be able to adapt something


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## bearclaw (Nov 2, 2011)

Thanks but I am cheap and only need to make 4 joints.


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## rwl7532 (Sep 8, 2011)

bearclaw said:


> Thanks. The only problems with guitar jigs is that they are using short stock. I am trying to scarf a 5foot piece onto a 12 foot piece and their jigs are too short. Still I might be able to adapt something


I watched the guitar jig vid. If done on a band saw, a long piece merely needs to be supported beyond the band saw table.

I make a temporary support using my jointer when band sawing a long piece. Two uprights and a cross member. All held together with C clamps.

Did you have a preferred shop tool for doing your scarfs?


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## jw2170 (Jan 24, 2008)

bearclaw said:


> Thanks. The only problems with guitar jigs is that they are using short stock. I am trying to scarf a 5foot piece onto a 12 foot piece and their jigs are too short. Still I might be able to adapt something


I must be looking at this from the wrong angle....

You say the pieces are only 3/4" x 7/8", so at 12:1 this should only need a scarf joint about 9" long?


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## rwl7532 (Sep 8, 2011)

jw2170 said:


> I must be looking at this from the wrong angle....
> 
> You say the pieces are only 3/4" x 7/8", so at 12:1 this should only need a scarf joint about 9" long?


If the 7/8" face has the scarf = 9"
If the 3/4" face has the scaft = 10.5"

(3/4 x 12 = 9 and 7/8 x 12 = 10.5)

The 9" and the 10.5" inch measurement is not measuring the hypotenuse of the triangle created.


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