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I have worked out my technique for routing the neck dovetail. I am doing this for OLF SJ models. Cutaways and regulars. I'm working the normal body now. Question is whether I should flatten the side at the joint or sand relief into the tenon area to deal with rounded shape.

I prefer to flatten the rims. For me, the less I have to mess with the neck itself the better.

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George :-)

Crud. It has occurred to me that if I do not flatten, then the dovetail joint may not be tight enough if I go the "relief" rout (I would have to go down deeper in the joint, but my current setup produces almost a level neck tp top). Shims?

I prefer to leave the sides rounded and then relieve the heel so there is only about a 1/8" of material bearing on the surface that needs to be flossed.

I'm no dovetail expert (and surely one of ours will jump in here) but when they are loose I use a shim of the same type of wood and some HHG.

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Steve Smith
"Music is what feelings sound like"

I should clarify that I've never made an OLF SJ model. I was commenting in general terms. No matter the shape, like Steve, I leave very little edge to be flossed when mating the surfaces.

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George :-)

I think I'm gonna punt on the dovetail. I just can't seem to gain enough confidence in what I'm doing. I'm just gonna do a M&T. Way less estimating and calculating. If I get it wrong, I'm toast.

Now, questions are, cross dowel or threaded insert? I've had a threaded insert fail, so I'm leaning towards cross dowel (barrel nut). Also, where does one source those brass bolts with wide heads and Allen insets?

Lowe's and HD has them, so does McFeely's online.


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I found them at Lowes. 1/4 by 20 threads. Brass inserts (keyed). 40 mm connector bolts.

Mike, I have nothing to offer your actual question / problem. I only need to say that I love the way you identify guitar shapes as "cutaways and regulars." That's awesome!! So far I've only built "regulars."

Well, what do you call them? :p

Ok, so I worked up another sample neck and block, used the 14 Fret M&T templates. I did use a piece of sacrificial wood at the top of the block to minimize tear out, that worked great. 1/2" spiral bit. But look at the size of the mortise (length is 3.4"). My actual heel will cover that, but when I measured how that would be on the body, it would go to the blue tape line. And, properly set, there would be about a 1/4" gap between tenon and bottom of mortise. Seems that the mortise is just too long. I can adjust up with the edge vise. But the guide line will be north of the top. Is that advisable? Normal?

Mike

Well.... I don't have much choice on tenon size, and I measure 0.2" based on full seating in joint (last picture), so I'm gonna move template north by 0.2".

It worked. Have to say, next to cutting the binding channels, that was about the scariest thing I have done yet. The neck jig worked as advertised. But, I still wish the templates allowed for more outside edge cutting. Guess I will pony up some money and ask for it. I still don't understand why the mortise is 0.2" longer than it needs to be. The joint is simple. I must be missing something here.

Couple of pictures showing the progress. Kind of a big deal to me as I feel like I'm taking on new challenges. If you look closely in the background, you will see the African Blackwood bevels for this project.

Yup, there is a Southpaw in the mix. That one has been a challenge. I have had to constantly remind myself.

I'm running a risk here. I'm not being critical. I just need to know if anybody has a work around for cutaways. The edge vise I have will not work on a cutaway. I've got to get these cut, any help would be appreciated. I'm considering building a caul that will fit into the cutaway, secured to body with double sided tape and clamps. Why is this so hard?

I'm looking for ideas on how to non-destructively modify this edge vise so it can be used on cut always. Thanks in advance

Mike

Two ideas:
1) EASY - run a thin but rigid caul on either side of the body (under the clamp) to extend the cutaway. Add stiffeners between the cauls to keep them from collapsing. Use if clamp can open wide enough.

2) HARDER - build another clamping apparatus for the inside of cutaway, which clamps into the void of the original clamp.



Sorry about the crude drawings - it's late.

Thanks. Have you tried that design? One of the issues is vibration due to cutting torques. I built a caul and secured with carpet tape. External clamps are difficult, if not in the way of the neck jig. A shim across the front and back add extra hold forces on dogs and caul. I really holds tight, but I'm not sure it will tolerate cutting torques. And, I have to probably make 5 of these.

When u stop and think about those ideas, the two bad things are potential movement, and non level orientation of edge vise. The latter will result in a mortise that is slightly narrower. Vertical alignment is not an issue. So if hold forces are good, it should work.

Here are some other angles on it. The drawing is the proposed new edge vise design by LuthierTools. My engineer's eye sees a problem with it in that the angled ledge won't register (except at the midpoint) with a curved surface. Does anyone see it different?

Yep. Upside down. The southern hemisphere solution.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

Nothing relevant to add, but that looks like it's going to be a beautiful guitar, Mike.

Thank you!

I'm thinking it is going to be weeks before I get the new jig, so I *MIGHT* try the setup I showed above unless someone talks me off the ledge.

Mike

I went ahead and tried the cut. Went fine. I added a transverse clamp to the caul to make sure nothing could move. Went pretty good.