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I am attempting to cut my first dovetail joint without ever seeing the joint first hand. I purchased the dovetail template from StewMac and fabricated the necessary jig. Question, how close to the back plate are typical dovetail mortises cut? This important question was left to the users choice in the instructions that came with the template.

Jack

 

I spent a good week figuring this one out and building jigs. Mine are hanging together it seems. Gosh, I could tell you how to do it and rob you of the joy of accomplishment.

Just kidding, actually it's been so long since I built my jigs I forgot how, I just cut the joints without thinking about it now.

You'll figure it out. Mine are made from scratch, the neck dovetail jig is solid maple base with a mahogany block. I use a Klemmsia clamp to hold the neck blank in position on the truss rod slot, and cut away. I use two router bits a straight cut to hog out the wood in two passes, deeper on the second pass.

Then I switch to the Freud Dovetail bit and cut the joint on the neck.

The Body neck block is cut after my rimset is together, I clamp the rim into my walnut base and again, cut with a straight bit on two passes, third pass I switch to the dovetail bit.

I'm leaving for Colorado in the morning, or I'd snap you some pics. My advise, Build you a Woolson Jig and be done with it. Good luck.

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http://www.dickeyguitars.com

Hey Jack,

Welcome!

I think mine are something like 1/2" - 3/4" from the back plate. I really don't know if there is a rule as to how close it should or should not be. I just like to make sure that it is not so close to the back plate. I'd be interested to hear what some other people have to say.

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Josh House

Canadian Luthier Supply
http://www.canadianluthiersupply.com
https://www.facebook.com/canadianluthiersupply?ref=hl
House Guitars - Custom Built Acoustic Instruments.
http://www.houseguitars.com

Jack:
I've just finished a course where we used dovetail joints (and router jigs) for the necks.
The dimensions were the same for all guitar models (including classicals).
The diagrams of the jigs I have in my notes show that the dovetail is about 3 1/8 high or so. (I haven't worked out the details, taking into account the bearing and bit sizes.)
There's a fair bit of end block and side intact below the dovetail- depending on the height of the sides.
If you let the dovetail get too close to the back, the heel of the neck can get a little clumsy (or you might shave into the dovetail when you are carving the heel).

Cheers

John

John makes a really good point. On one narrow neck bouzouki I was building I made the dovetail to wide and ended up carving into it at the heel. Some creative wood working and you can't really tell, but it is something to watch out for. Body depth at the heel block will certainly be a big factor in how much space there is.

_________________
Josh House

Canadian Luthier Supply
http://www.canadianluthiersupply.com
https://www.facebook.com/canadianluthiersupply?ref=hl
House Guitars - Custom Built Acoustic Instruments.
http://www.houseguitars.com

Hi and welcome,

I cut the female body dovetail 1/8 " deeper than the male neck dovetail so they don't touch when joined and glued. The angle you choose on the neck is an important consideration. I've used the SM jig but now use the Woolson Neck Tenon Jig, which is available for the plans library at the top of this page. This jig makes the neck angle a no brain-er.

I have found practicing on spruce 2x4's a good way to become familiar with the joint.

Bruce, that straight bit idea is a definite keeper, Thanks.

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Michael Lloyd

“I was born to ignorance, yes, and lesser poverties ...
I was born to privilege that I did not see ... I didn’t know it, but my way was paved” – John Gorka

I'm presently working on a small concert guitar with a total body depth at the neck of 3.32". Any comments?

on a thin body like that i would extend the dovetail tenon to within at least 3/4" of the end of the heel, down to possibly 1/2".

there are nor hard and fast rules on this.

Here's an image of 3 1/2" body at the neck (unfinoshed). I've cut the depth in the body 1/2" from the back plate and I agree that less does not give you much room for error.



The red line represents the depth of the tenon and the green line the depth in the body. So there remains a space here.

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Michael Lloyd

“I was born to ignorance, yes, and lesser poverties ...
I was born to privilege that I did not see ... I didn’t know it, but my way was paved” – John Gorka

I stop the female part of the dovetail just about an 8th in short of the binding and then cut the mail until the fingerboard plane is about 3/16 above the top plane and fit the rest by hand. This allows room to adjust the neck angle if necessary. I too use the SM templates in a homemade jig that allows the neck angle to be matched in both the box and the neck.

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Tickle your guitar daily, and it'll tickle you back.