Official Luthiers Forum!

Hi

I have the stew mac neck mortise and tenon router templates. I will be using the bolt on method. When I do a test on them there is a 1/16 gap in the side fit. Meaning I can slide in a 1/16 drill bit to get the joint to be snug.

Is this normal/desirable to allow for adjusting/setup?
Do I just add loose shims when attaching the neck?
Or do I modify one template to get the fit tighter?

I don't see this as a big problem. Just wondering what others do.

Thanks

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Rick Hubka
Chemainus BC Canada

If you are talking side to side ? I think you may have the wrong bit for your router. This should be a tight fit. It is normal for an opening at the bottom of the joint but not the sides .

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Yes... I'm talking side to side.
I'm using a router template/copy bit with the bearing being the same size as the bit.
Could someone using these Stew Mac templates measure theirs for cut size and post them here?

Thanks

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Rick Hubka
Chemainus BC Canada

Hi Rick,
I purposely leave the mortise over 1/16" to 1/8" bigger than the tenon. This gives you plenty of room to make sure that the neck aligns perfectly with the centerline. Much of my neck work is not heavily jigged and so I just like having a bit of a buffer in case something doesn't get aligned properly. Besides, all that matters is that the cheeks of the tenon fit snugly to the sides.

The neck joint needs to be tight. Having a neck joint with that much slop in it is not a good thing. I have a number of suppliers that I get mortise and tenon necks from . All joints are tight. I have a jig that is much like the stew mac. It makes a tight joint. I would rethink my process and make the joint more stable if the joint has so much play.
You may need a precision router base pilot to make it work and not a flush patterning bit. Some jigs are designed that way. To make a neck match the top center you can use a pair of pilot holes that match the top and neck block together. I use a 1 1/2 inch spacing for 2 1/4 inch dowel holes. The holes are 7/8 from the rim . That way when I set the top , the neck block will be centered to the top.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

With all due respect I'd take an opposite view. On a total bolt-on neck I see the tenon mainly as a device to hold the anchoring hardware.
I've used the StewMac templates on most of my instruments and actually like the little bit of slop. The side to side/up-down movement is limited by the size of the holes in the headblock which I think most of us make a little larger than the bolts anyway. (5/16 vs. 1/4 in my case) The slop allows a little fudge factor in aligning the hardware. A lot of well regarded makers simply use a butt joint with no tenon and slightly oversized holes.
I've started making the mortise on my headblocks on the table saw before installation rather than use the templates and a router. I still make the mortise a little bigger.
TJK

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It's not what you don't know that hurts you, it's what you do know that's wrong.

You can do it as you wish but a neck joint needs to be as solid as possible. If you are building to sell , you will soon find that good enough, inst good enough. Having slop in a neck joint or any joint on a guitar is not a good thing. Of use that do this professionally we often discuss these kind of options and all that I speak to are in agreement . A proper joint will fit well. Not forces but not sloppy either.
If you do it as you suggest , How can you control the neck if there is any shrinkage in the neck block? I have seen too many bolt on necks that need adjustment as age and stress settles in .

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Do I understand correctly John that If you are making a bolt-on neck with a tenon you have a snug fit on the tenon and the bolt holes in the head block are exactly the same diameter as the attachment bolts? I would think that even with a snug fit, if the guitar dries out and the head block shrinks a little the bolts still might need to be tightened. What are your feelings on the adjustable necks like Rick Turner and Mike Doolin make and also the butt joint bolt-on technique without a tenon like Mario uses?
TJK

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It's not what you don't know that hurts you, it's what you do know that's wrong.

I am a traditionalist builder but when I do use the bolt on the joint is still glued. The bolt is nothing more than a clamping device. For those that do us adjustable necks I doubt they have as much slop as was talked about in the above post .Martin has started using an adjustable neck joint. This is nothing more than a sliding tenon but is not sloppy side to side. These joint have been around for a long time and are not new. I don't have any issue with them I just prefer to use old style neck joints. I love the simplicity of a dovetail . My bolt holes are a 1/64 larger than the bolt I use. I don't think much of butt joints for necks.
The point was more about a sloppy fit to which I still say , a neck joint should be a snug fit , Too much play and you won't be able to control it.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Thanks John.
TJK

_________________
It's not what you don't know that hurts you, it's what you do know that's wrong.

you are most welcome. I know there is more than 1 way to do things. I have learned in my time what not to do.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Thanks for the reply's

Today, I made a new tenon template from scratch using the router mounted under my table saw. If I'd known it would be that easy to make one I could have avoided this whole problem.

Now I have both. My Stew Mac template with slop and a new one without slop.

I appreciate the 2 schools of thought on this joint being tight or loose. I try to make my jigs with very tight tolerances so will first opt for a tight fit.

Thanks Gang

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Rick Hubka
Chemainus BC Canada