# Getting a perfect scarf joint?



## sehnomatic (May 8, 2014)

The scarf joint is a simple idea with simple execution, but hell is it hard to get perfect. I'm currently trying a scarf jointed 3 piece maple neck with black lams, so the alignment must be absolutely perfect.

*How do you guys get perfect, repeatable scarf joints?
*
Here's my technique, as of:

1. Cut neck and headstock parts with angle of choice
2. Clamp the joint dry, ensuring the joint is clean, and the fretboard surface is flat.
3. 1 dot of glue and clamp into perfect alignment,
4. Wait until it's dry and drill holes for allen wrenches.
5. Break the joint and fully glue the joint this time.
6. Use holes and fasten to prevent moving and clamp.

Why not glue immediately?
Pieces will slip and slide, even if perfect alignment is reached, it will still move during the dry time.

Why not drill holes while dry clamped?
The drilling vibration, coupled with clamp compression will make the joint slip while drilling.

Why allen wrenches?
Screws can break the thinner parts of the two pieces and nails are a pain to remove.

Otherwise the options are: Put a black veneer between the pieces to hide any difference, use a solid headstock piece, or do this joint again and veneer it.

Any improvements? Good enough? Like it? Any other methods? Any thoughts are welcome.

Thanks in advance.


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## BlackMastodon (May 8, 2014)

sehnomatic said:


> The scarf joint is a simple idea with simple execution, but hell is it hard to get perfect. I'm currently trying a scarf jointed 3 piece maple neck with black lams, so the alignment must be absolutely perfect.
> 
> *How do you guys get perfect, repeatable scarf joints?
> *
> ...


I do the dry clamp, screw holes, and glue with nails to keep it alligned method. I just flatten it a bit before gluing the fretboard anyway.

Also, my buddy (who's been a wood worker for 5 years now) and I got on this discussion about the scarf joint and realized why that method you linked is the inferior one). The reason why the more traditional scarf joint holds better is because the truss rod keeps the headstock piece in place from the string tension, adding more strength to keep the joint strong. With that method, the truss rod doesn't have any added strength to the headstock piece and it's only being held by the glue from the string tension. In both of our opinions, that headstock method is very prone to cracking and damage, and should probably be avoided.


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## Purelojik (May 8, 2014)

interesting style. i'll have to try it. I usually just glue a separate piece altogether and shave off the difference. Its less stressful and gets a great result every time. its always better to have more wood protruding above the area which with receive the fretboard, than to have the headpiece slide below it. I do this because i dont have access to a planer or jointer. This method allows me to make a pretty killer joint as well. 











http://zerofret.wordpress.com/2014/03/22/cleaning-up-the-scarf/


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## AKan (May 8, 2014)

I roughly-cut the angle on the blank with my bandsaw, and then take it to a belt sander to make sure it is flat. Once I do that, I just go ahead and glue/clamp the headstock, giving it a bit of extra space to allow for the expected slipping. I've never found the need to use screws for alignment, even given a situation where I need laminates to line up correctly. 

Works every time. Est. time: ~10 min/joint.

Your method appears sound.


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## JEguitars (May 8, 2014)

I use a bar clamp and clamp the side to hold my scarf joint in place while I place the vertical pressure on it with other clamps, then release the bar clamp and tighten the rest of the clamps, really saves me a lot of hassle.


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## sehnomatic (May 8, 2014)

Took a little from everyone. The headstock part still stands 1/32" proud, I need to sharpen plane blades before continuing any work.

I ended up placing a veneer piece in between so that the most minute misalignment wouldn't be the end of the world. I soak my laminates in diluted glue and as a result, break tests resulted in broken maple.

Aside from the obvious seam, we've got perfect alignment!









I'll start a build thread for this 99% blackmachine influenced build soon. Figured ebony?


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## Slunk Dragon (May 9, 2014)

I heard black magic works wonders.

(But seriously, mad props to you dudes doing these. I'm definitely taking notes!)


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## Berserker (May 9, 2014)

This is the method I use. I find cutting the joint more difficult than gluing it, never had an issue this way:

Luthier than thou » Blog Archive » Simplifying scarf joints&#8230;


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## darren (May 9, 2014)

I really don't like the "halfway down the headstock" scarf joint. It really has too little glue area, unless you are always going to laminate a face and rear cap to strengthen the headstock. 

I much prefer the "under the fretboard" method, as you don't get grain run-out at the headstock joint, which makes it notoriously weak.


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## UnderTheSign (May 9, 2014)

darren said:


> I really don't like the "halfway down the headstock" scarf joint. It really has too little glue area, unless you are always going to laminate a face and rear cap to strengthen the headstock.
> 
> I much prefer the "under the fretboard" method, as you don't get grain run-out at the headstock joint, which makes it notoriously weak.


Agreed. 

Plus if you're a scarf joint wizard like Searls, you can get some pretty damn flashy looking joints.


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## eddiewarlock (May 9, 2014)

I have done a few scarf joints...it is stressful. 

But i have gotten good results ( knocks on wood  ) I cut the angle,and then with a router bit with a bearing on top, make the cut cleaner, and then lay sandpaper on a perfectly flat surface and i clamp a fence, so i am at 90º, i make sure it is perfectly flat.

Check with a square and then proceed to clamp.

I have to admit than on laminate timbers it's even more stressful...


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## VanDewart Guitars (May 9, 2014)

I use the scarf in the headstock design combined with a faceplate to minimize the appearance of a joint. I've never had any problems with strength issues or headstocks breaking, and I have some pretty thin and narrow headstock designs. If your joint is tight, the glue area will be stronger than the wood, and if you don't have grain runout, your wood will be plenty strong. I think that having a strong headstock design is equal parts wood selection and good woodworking.


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## canuck brian (May 9, 2014)

I cut the angle on a tablesaw with a fine blade to leave a pretty uniform, super flat surface. Then i glue a 1 piece headstock on, keeping it originally in place with tuck tape (incredibly high tack tape). After that, two parallel clamps seal the deal.


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## RV350ALSCYTHE (May 9, 2014)

canuck brian said:


> I cut the angle on a tablesaw with a fine blade to leave a pretty uniform, super flat surface. Then i glue a 1 piece headstock on, keeping it originally in place with tuck tape (incredibly high tack tape). After that, two parallel clamps seal the deal.



How do you set your blade and how are you pushing the piece across the blade to get such a steep angle?

Currently I've had to use the bandsaw to get the angle and it leaves a rough surface. Followed by block sanding until both surfaces are close (pain in the ass and takes a while to remove my saw marks).

I can't imagine how to cut the scarf on my table saw without holding the piece at a strange angle and working dangerously to get it right.
Is there a type/style of jig to help with cutting a scarf?


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## djohns74 (May 9, 2014)

RV350ALSCYTHE said:


> I can't imagine how to cut the scarf on my table saw without holding the piece at a strange angle and working dangerously to get it right.
> Is there a type/style of jig to help with cutting a scarf?


That would be a taper jig, I use this one:

Precision Taper Jig - Rockler Woodworking Tools

Though it would be fairly straightforward to build your own, I imagine. I've modified it to attach a couple of pieces of mahogany to it to give a taller surface to clamp to and it's since been a very repeatable process for me. What with angling the table saw's blade, this even works just fine for compound scarf joints, which has been a nice surprise.

For wider blanks, my table saw is not able to do a through cut on the entire piece, but it's easy to use the band saw to finish those cuts or even do it by hand. I probably wouldn't attempt a scarf joint any other way at this point.


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## canuck brian (May 9, 2014)

RV350ALSCYTHE said:


> How do you set your blade and how are you pushing the piece across the blade to get such a steep angle?
> 
> Currently I've had to use the bandsaw to get the angle and it leaves a rough surface. Followed by block sanding until both surfaces are close (pain in the ass and takes a while to remove my saw marks).
> 
> ...








This is what I use. Press it against the fence and keep it flat.  The only necks i can't go all the way thru are the 8 string ones and I just bandsaw the rest off because its not going to be used.


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## immortalx (May 9, 2014)

For the perfect alignment of the laminates, the trick that works for me is to make sure the laminates are square before gluing, not just flat on their gluing side.
The reason is that you can have perfect gluing surfaces but they might be non-parallel to each other. The laminates could line up perfectly on the outer part of the neck blank but not inside (and unfortunately you can only find out once you carve the neck).
I also drill 4 holes (at points that will be cut off) and put toothpicks to make sure nothing moves.
I found that i get consistent results with this method.


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## UnderTheSign (May 9, 2014)

Man, you stateside/Canadian guys all seem to have real tiny tablesaws!

Most table saws here have a sliding table which is a damn dream. Add to that a peripendicular fence and/or angle guide and sawing scarfs is easy.


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## djohns74 (May 9, 2014)

UnderTheSign said:


> Man, you stateside/Canadian guys all seem to have real tiny tablesaws!
> 
> Most table saws here have a sliding table which is a damn dream. Add to that a peripendicular fence and/or angle guide and sawing scarfs is easy.


That is one of the sexiest things I've ever seen. 

However, not exactly the most practical thing in the world for a basement builder...


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## RV350ALSCYTHE (May 9, 2014)

UnderTheSign said:


> Man, you stateside/Canadian guys all seem to have real tiny tablesaws!
> 
> Most table saws here have a sliding table which is a damn dream. Add to that a peripendicular fence and/or angle guide and sawing scarfs is easy.



Shit if I had 10 grand I'd be using that as well!
For now I'll have to make due with my mastercraft $100 portable table saw 




canuck brian said:


> This is what I use. Press it against the fence and keep it flat.  The only necks i can't go all the way thru are the 8 string ones and I just bandsaw the rest off because its not going to be used.



Thanks for that picture, that's exactly what I've been trying to figure out!



djohns74 said:


> That would be a taper jig, I use this one:
> 
> Precision Taper Jig - Rockler Woodworking Tools
> 
> ...



Awesome! for that price I'll definitely be picking one up.


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## ChAoZ (May 10, 2014)

Make friends with your local joiner who has the flash table saw and heaps of other useful woodworking machines and knowledge


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## darren (May 10, 2014)

I made my own purpose-built sled for my bandsaw. I was doing them on the table saw, but with a 10" blade, i can only reliably get about a 3-4" cut, which sometimes isn't enough. With a good blade, i've been getting great results with the bandsaw and a small hand plane to true it up.


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## ElysianGuitars (May 10, 2014)

I bandsaw too, but don't plane the surface, I sand it on my sanding plate. My sanding plate is simply an onyx sink cutout I got from a countertop maker, it's very flat, and I use spray adhesive to adhere some 80 grit sandpaper to it.


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