Triple O - Dovetail neck doesn't seat - Photos

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Blake Porter
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Triple O - Dovetail neck doesn't seat - Photos

Post by Blake Porter »

-Stewmac Triple O Kit
-First Build

Anyone see a problem in the photos? Or have ideas for me?

My dovetail neck doesn't seat all the way into neck block.
Everything seems clean - I re-chiseled edges, etc. I'm not sure where, or what is stopping the fit???
What approach should I take here?
Thanks!!
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Barry Daniels
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Re: Triple O - Dovetail neck doesn't seat - Photos

Post by Barry Daniels »

Is the dovetail hitting the bottom of the mortise? You can determine this with some careful measurements.
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Bob Gramann
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Re: Triple O - Dovetail neck doesn't seat - Photos

Post by Bob Gramann »

Please excuse me if I’ve misread this and tell you stuff that you already know. It’s been 28 years since I started doing this by building a kit. My kit was from Martin. The dovetailed neck and dovetail block were supplied overly tight so they could be fitted after the guitar was made (the thickness of the top and sides affect the fit). I suspect that you’ll need to fit yours. I checked the StewMac kit instructions. They have a section on how to do this. It is correct, but there might not be enough description to make it clear to a first-timer. There are several youtube demonstrations and several descriptions you can google for on how to chalk fit a dovetail joint. Watch and read a bit until it makes sense. It’s not hard. The major requirement is patience. Unless you have already taken this into account, you need to worry about the neck angle meeting the body so that the strings will end up the right height above the fingerboard and the bridge. The fit does need to be perfect. You can’t enhance a bad fit with extra glue. When it fits right, the smallest amount of glue will be sufficient. Enjoy.
Last edited by Bob Gramann on Wed Dec 16, 2020 6:41 pm, edited 1 time in total.
Freeman Keller
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Re: Triple O - Dovetail neck doesn't seat - Photos

Post by Freeman Keller »

First, check as Barry suggests - possibly with carbon paper or chalk. Alos make sure there is a gap at the end of the tenon so it is not hitting the mortise there either.

Second, do you totally understand how the dovetail works (I didn't on my first couple). As the neck drops into the pocket it pulls the heel checks into the body. You want the entire length of the tenon pulling mating against the angled sides of the mortise. I have the best luck chalk fitting that also - rub chalk against one part or the other and see where it transfers. And as you floss the cheeks the neck will drop down more.

Good luck, that is one of the hardest parts of your build.
Clay Schaeffer
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Re: Triple O - Dovetail neck doesn't seat - Photos

Post by Clay Schaeffer »

Something to keep in mind is that the joint is initially made overly tight so adjustments can be made in all three axis. By careful sanding and fitting you can change the neck angle in relation to the top and centerline of the guitar, and also move it slightly to the left or right on the body. Uncareful sanding and fitting will also do this, just not the way you want it.
Alan Carruth
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Re: Triple O - Dovetail neck doesn't seat - Photos

Post by Alan Carruth »

Good advice so far.
Bob Gramman wrote:
" It’s not hard. The major requirement is patience. "

Another major requirement is a sharp chisel.

This is one of the operations that embodies the 'kaon of lutherie': "The slower you work the quicker you get done". The idea behind chalk fitting is that the chalk marks the high points. You're trying to get things to fit with no more than a few thousandths of an inch gap; not much more than the thickness of the chalk. If you remove too much wood the joint won't be as tight and strong as it ought to be. You can push a dull chisel through a heavy cut, but you can't take a light cut with one. Ideally, all you want to do is take off the chalk and a layer of wood that amounts to dust. Even the finest shaving might be too much. The hardest job for my students has been neck fitting, and the biggest reason is that they take off too much wood. You can't get into too much trouble taking light cuts.

The hardest part of the dovetail to fit is the round part at the bottom. Of course, that's the part that needs to fit the best. A fine sharp triangle file might be the best way to do that.
Marshall Dixon
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Re: Triple O - Dovetail neck doesn't seat - Photos

Post by Marshall Dixon »

The mating surfaces of the sides are rounded and the neck surfaces are flat.

I like to under cut the inside of the neck surface leaving about 1/8" of contact area. The sides I carefully sand perpendicular to the centerline of the top. Even so, a quarter degree offset will skew the line and for that reason I put the fingerboard on after the neck is attached. Then put on the peghead veneer that has been cut at the correct angle to meet the nut. Pay attention to the bottom of the joint as has been mentioned. Chalk one surface at a time. I make adjustments on the neck only, leaving the body joint alone (since it's easier to make another neck).

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How to correct your problem? Square just the mating surface of the sides or contour the neck. To contour the neck would be difficult and with fingerboard attached doubly so. Sanding the sides to line up the neck perfectly square presents it's own challenge but it looks like you might just have enough wood to make it work. It looks almost as if this kit has been prepared to do that. I'd suggest calling Stew-Mac and asking them.
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Blake Porter
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Re: Triple O - Dovetail neck doesn't seat - Photos

Post by Blake Porter »

Wow! So many great replies. I had no idea about chalk fitting, etc.
I've been pouring over each reply and watching videos.
Grateful to each of you!
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