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Hello again. So, I just finished the body, and now I admit I am starting to get a little nervous. The binding and purfling is making me nervous. The fitting of the neck is making me real nervous. While I am hashing out what method I want to use to route the binding and purflings, I am also looking ahead a little at the fitting of my neck.

When I sat the neck into the dovetail for the first time it was glaringly obvious that I will need to do some work to it. There is around a 3/64" gap between the back of the neck's dovetail and the front of the Front Block. This is obviously something that needs to be touching when I glue it.

In my mind I can do 3 things. I could sand the back part of the dovetail (the part of the neck that sits flush on the outside of the rim) so it can go back further. Or, I could add a shim to the Front Block. Or, I could trace the shape of the neck and mortice into the rim so everything can go back.

Please look at the picture below and give me some ideas. I would also like to know about the dovetail's bolt on neck joint. The kit DIDN'T come with a bolt. Nor is the hole in the Front Block lined up correctly. Is this something I should utilize? I'm not sure how it works???? I picture a hole completely through the Front Block. Once the neck is attached and glued a bolt will be fed from the inside of the guitar through the Front Block, sucking the neck into the Front Block. Am I far off? Thanks guys.

The face of the neck should be flush with the top and the cheeks of the heel should sit nicely on the rims; the neck should be centered (not tilted side to side) and the dove tail should be tight.

There is no need for the back of the dovetail to be in contact with the back of the mortice. What is important is that the sides of the tenon are in good contact with the sides of the mortice and when pushed in the wedge like shape pulls the heel cheeks tight to the rims.

The bolt was for manufacturing the neck and is not made to be used to bolt the neck to the block.

John Hall has some videos on how to fit a dovetail. Here is the first.

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http://www.Harvestmoonguitars.com

In addition to what John said the back of the dovetail should have a space between the neck and the neck block for the steam probe that will be inserted to loosen up the glue some day when your ax needs it's neck reset. That's how it's done and pretty much all conventionally designed and built acoustic guitars that are under string tension for anywhere from 5 years..... (we've seen it.....) to 30 years will need neck resets. Some guitars go longer but most don't.

Keep in mind that your mission is to craft the dovetail so that the neck is in the right angle left and right, back and forth to the body, bridge and saddle while at the same time having a snug fit of the dovetail with NO glue. The glue is applied as insurance and to hold everything in place.

A proper dovetail joint on a guitar neck is a beautifully engineered thing and will require some developed skill to get it right.

Since you are in Florida I also wanted to ask you if you are building in a controlled humidity environment? That's important if you want all things to come together well and stay that way.

Welcome to the forum as well!

Wow, great responses guys. I never would have thought that space was necessary. It's funny neither manual says that space should be there.
And the neck bolt johnparchem! I'm glad I asked cause I really created my own idea of how things would come together! And I was way off.
Hesh, because I do not have an air conditioned shop, just a garage at ambient air temperature, I am doing my build inside. I'm at 50% humidity in here. Thanks for asking.

Hey Devery happy to help.

50% is likely fine if the instrument stays in a similar climate. If it goes to say Arizona where it's drier cracking could occur.

I'm in Michigan and used 42 - 48% as my range and it's served me very well except for the client who left it in a hot car in Nashville for a week. Bridge lifted but no cracks.

So after much careful work I think I'm where I need to be. My center line is good, and my neck planes to a 1/16" higher from the top where the bridge will be. I have a little reservation though. When I stick the neck into the dovetail, if I push it down with my hand it's kind of loose. You can move it this way or that way. But it also sticks up a 1/32"-1/16". Once I "tap" it down and/or clamp it down to where it is supposed to be, then it firms up nicely. Once it is in this position--which is where it needs to be when I install it--I think/hope it will do the job. I tested it with the fretboard on top and everything sits nice and firm in position, it also lines up well with the bridge.

Thanks guys. BTW, that video in this thread was very helpful.

Can I ask a serious question that might go against the grain here?

What stops me from gluing/attaching the neck first (without the fretboard and without finishing/sealing the guitar)?

Both manuals, the videos, everything I've seen tells me to get everything where it's supposed to be then to set it aside for finishing. Why can't I simply glue the neck into the dovetail and work from there? I've dry tested it, even with the fretboard attached and it's good to go. I can't think of any reason why I can't glue it first. Actually, to me it seems easier. Once glued I could glue the fretboard on afterward, tape it up then finish/seal the guitar.

Like I said, I know this is going against all that everyone usually does. I'm not trying to rebel, I just can't find any reason why I can't do it this way. For me it seems easier. Are there any reasons why I shouldn't? Thanks

Most people find it more difficult to finish with the neck attached, but certainly some find it easier to attach first. I think it is just personal choice. Personally, I've always finished with neck attached as I do classical guitars, but I've just started a martin style 12 fret and I'm looking forward to finishing it neck off. That joint area has always been a challenge for me to finish as well as I'd like,
Mike

Thanks for your response Imbler. After working on it for several hours I feel I would prefer to glue the neck first. Let it dry, then glue the fretboard on. Then finish it. I just wanted to make sure I wasn't tempting the guitar gods.