Cutting neck joints

[dstretch]

Well I am still working on #4, (got sidetracked by a guitar). Anyways I am at the point of cutting my neck joint and I cant decide which joint to use. I am looking for some ideas for a jig to build. I don't want to reinvent the wheel so would anyone like to post some pictures of how they cut theirs? I have talked with Lloyd LaPlant and he uses a M&T joint and I am considering trying that joint. I read all the post regarding it and think that either joint (dovetail & M&T) are fine. Look forward to all the innovating photos of your jigs.

Thank all for all your experienced input.

Danny

[sunburst]

I use dovetail joints, because I just like them, but I don't feel any need for jigs.

[sunburst]

...

[dstretch]

WoW John

Do you cut all your dovetails by hand?

[sunburst]

Yup.

[Gail Hester]

I cut a straght dovetail in the neck block of the completed rim assembly with a bandsaw since it's flat at that stage. I also cut the neck with the bandsaw but with the neck mounted in an angle jig. I have several angle jigs for the models I build.

[martinedwards]

I rough it with a dremel, then tidy it with a chisel.

no big hassle, and no jigs!!

for guitars I used bolt ons with dowel bolts

[Stephanie Reiser]

If I were one of those who crank out 4 or 5 at a time, then I might understand having some kind of a jig or router system. But I only build one at a time. Like Gail, I have an angle base to hold the neck upside, so that I can slice off the little cheek segments. But they are merely slices, because I do the majority of the fitting by hand. Takes me a good afternoon to do the whole thing, but I am slow and in no hurry. The part John shows cutting with the dovetail saw I do on a bandsaw, but just for the initial cuts. I finish that part up with a 1/2" paring chisel.
How did that guitar turn out?

[Sam price]

I cut my cittern neck mortise and tenon by hand, no choice, because I am a one-at-a-time homebuilder with a family to feed, and no space or money for big flashy saws..

[amowry]

I use this bandsaw jig, which I think is pretty standard, to cut the dovetail. Because I like to angle the sides vertically, I have a piece of plywood that has a 1 or 2 degree taper planed into one of its faces, on which I set the jig when I cut the side of the tail. I cut one side, flip the plywood over to reverse the direction of tilt, and cut the other side. I use the same piece of plywood when I cut the mortise, so its walls will have exactly the same taper.

In my opinion, having a compound dovetail (one that is tapered vertically) helps immensely in the final fitting, because it is loose until it is almost seated home. If the walls are perfectly vertical, you end up with too much friction when you try to force the joint together, and it's much more difficult to make the heel the tighest area, which is the goal.

[amowry]

I think the most important thing is to make sure that the curved mating surface of the body is all perfectly vertical (or at least all in the same plane). When the ribs come out of the mold there might be slight irregularities that make it difficult to get a clean joint. With everything but an F5, I find I can touch up that surface with a spindle sander. For F5s I use Don MacRostie's jig for sanding the ribs in that area true. I don't have a photo, but it's a plywood frame that holds the body upright, and a half of a length of ABS pipe that has sandpaper stuck to the inside. The pipe slides on tracks and quickly sands off any irregularities. In this photo you can see the vertical sanding marks left from that jig. These have to be sanded off after the neck is attached.

[thistle3585]

How does the neck angle come into play in regards to your jig? Do you put the angle in the head block, the neck or both?

[amowry]

The neck angle is entirely in the neck. The bandsaw jig holds the neck at the correct angle.

[dstretch]

Andrew

Thanks for the pictures. I made a jig to hold my neck to cut on the band saw. Could you explain your 1 degrees pitch on the side?

Amanda Lyn

The guitar is going well. I started spraying finish yesterday. Here is a picture.

[amowry]

Nice guitar!

The pitch is just to make the dovetail narrower at the bottom than at the top. Mine ends up about 1/32" narrower at the bottom. The piece of plywood tilts the bandsaw jig, first to the right and then to the left, as you cut the sides of the dovetail (and also when you cut the walls of the mortise). I remove the plywood before cutting the curved sections of the motise, because those need to be vertical. That's why it's not in the photo.

[thistle3585]

Andrew
Do you have some sort of alignment system that lines up the bandsaw jig, or the body its self, on the tapered board?

[mandomaker]

Andrew, should a small, glue-covered wedge be gently tapped into the cavity at the dovetail joint shown in your photo ...then later cut off flush? I was thinking of doing this to snug mine up even more and could not think of a benefit to the gap. Thanks-

[amowry]

No-- the gap is there on purpose, so someone can inject steam into the joint if the neck ever needs to be removed. Also, if that area were a tight fit it would prevent the dovetail from pulling the joint closed.

Thistle-- no, I eyeball the plywood base parallel to the bandsaw table, and slide the jig on top of it. I think that the taper is so minor that the plywood would have to be really skewed to make much of a difference.

[Sitka]

Hey John,
what type of a saw is that?

and Andrew,
how does one achieve a uniform curved mating surface on the neck. I can't quite picture it in my mind.

Micah

[sunburst]

It's just an old Diston dovetail saw.

[billhay4]

Micah,
The Diston saw is what is called a back saw bacause it has a thick strip of metal at the top to support the thinner blade. They cut a thin kerf (thinness varies with the saw) and are commonly used to cut dovetails and other joinery. Takes a fair amount of practice to use one well, plus a very steady hand, and John has that.
The curved mating surface comes naturally from the curve that is carved into the heel of the neck. You do the outside shaping of the heel first and then cut the dovetail. The curve follows the curve of the heel. As long as the dovetail itself is a snug fit, the curve will be, too.
Bill

[mandomaker]

Andrew...Wow, I'm glad I asked! Thanks for the advice.

[dstretch]

Here is my 5 degree dovetail box thinga majig. Still afraid to try it.

[thistle3585]

Anyone have an end shot of a dovetail?

[Stanley Cox]

Danny, I know you are going to make the 1st. cut in scrap using the "dovetail thingamajig" but I am going to suggest it anyway.

Stanley