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I am just in the process of finishing my current build, a parlour sized guitar, and for some unknown reason I decided to try and fit the neck after about 10 coats of finish (Liberon Finishing oil) and thought i would check that the neck is centered etc just encase it needs any tweaking at the heal before applying the last coats of finish and it was a good thing I did.

Now here comes the problem, the neck is no longer straight with the center of the body and needs a significant amount of adjustment to get it right. I have flossed the relevant heel and now things are straight, but the 12 fret (body join) is now noticeably no longer straight with the centre line of the body. I am guessing that the fretboard must have slipped during glue up, and for some unknown reason (i'm sure i have checked things several times) I have not realised.

I am trying to work out my options and as I see it there are a few possible routes.

1. As the guitar is for me ignore the problem, and when fitting the bridge off set it by the same amount (1mm ish) and move on to the next build.

2. Keep the bridge square and adjust the saddle to compensate for the problem.

3. Make a new neck.

This is very frustrating as i was so near finishing the build, but i am thinking that option 3 is the most sensible option.

Does anyone have any suggestions or other possible fixes that i have not thought of yet!

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Nick

Follow my musings on getting started in luthiery http://www.tredwellinstruments.co.uk

So the frets are not perpendicular to the centerline of the fingerboard? They are all parallel to eachother, correct? Not just a poorly cut slot, or fan frets?

That problem can happen during the tapering of the fingerboard, if the two tapered edges aren't equally offset from the centerline. Possibly during glue-up as well, but to get a whole mm difference between the ends of a fret would make more like 6mm difference between the ends of the board (that is, nut end offset 3mm to one side, and soundhole end offset 3mm to the other side), which if you shaved it straight again, would lose a lot of neck width... unless you glue the fingerboard to the neck before either of them is tapered. Another place it could happen is if you taper the board before cutting the fret slots, and cut them square to the tapered edge, rather than square to the centerline.

Which direction is it off? Does it make the saddle more slanted, or less? If less, then definitely keep it. Guitars have been built that way on purpose, putting the compensation slant in the frets instead of saddle But if it makes the saddle more slanted, then people might notice and wonder what you were thinking, but it's still just a visual problem. I'd take option 2 from your list.

Let's see some pics.

1mm sounds not very far out of whack. If all it means is ha the bridge will be off the centerline 1mm I'd chalk it up to experience, move on, and try not to repeat next time...

I wouldn't consider 1 mm to be off centre . Undetectable even to my mechanical eye. 1 cm yes. 1mm is a thick pencil line.

I did the same thing in my parlor. For some reason after the fretboard was slotted and glued on the centerline of the neck was off center of the guitar body. It was a tad less than 1mm so I wasn't too concerned about it but I did make sure the center line of the neck was exactly parallel to the center of the guitar body. When I glued my bridge on I made sure I centered it with the neck and not the body. I also ended up shaving just a touch off of the one side of the heel because I could see it was not quite centered. I did all this before finishing so you may just want to leave the heel alone.

I think as long as the centerline of the neck is parallel with the center line of the body I think it will be just fine. At least that is what I did and I don't have any issues with the guitar and how it plays.

Bob

Why not just fix the joint so the neck is correct?

Is this a bolt on butt joint or tenon joint? Or is it a dovetail? Any of those can be adjusted to shift the neck. If it's butt joint and bolts, just enlarge the holes a smidge and re-floss the joint. Or shave one side of the tenon, etc...

I usually do the initial fitting of the neck when the body has its first coat of sealer, and then do any minor adjusting as needed after finishing. How do other people deal with neck fitting?

Thank you for all the replies, I have taken a couple of pictures to help show the problem.

The centre line of the neck is lined up with the centre line of the body and the frets are perpendicular to the centre line of the fretboard as well.



but here is the issue



As you can see the fret at the body join is tilted downward on the bass side by around 1mm. Measuring from the top of the fretboard to the body, there is a 1mm difference in length between the two sides of the fretboard with the bass side being longer.

I'm currently thinking my option 2 is probably the best solution. Its a completely removable neck so if it really does not work, i can always make a new neck in the future.

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Nick

Follow my musings on getting started in luthiery http://www.tredwellinstruments.co.uk

It looks like you may have gotten the fret board skewed when you tapered it.

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Steve Smith
"Music is what feelings sound like"

Nick,

If as you say the centre line of the neck is lined up with the centre line of the body (and assuming that the centre line of the top matches that of the rimset) and the frets are perpendicular to the centre line of the fretboard as well, then the upper bout of the body must be marginally asymmetric to this centre line, hence your second picture. I'd claim this as a new "design feature" and fit the bridge based on the neck as you have it in picture one. It's a cosmetic issue.

If the visual mismatch annoys then it's a new body not a new neck that you need to build

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

I have more questions/suggestions...

Are you certain your fingerboard is correct? Measure from the nut to the last fret. They should be the same length. If they aren't, could be your frets are skewed which will cause all kinds of mayhem.

For curiosity, measure the squareness of the body to the centerline by the neck. It could very easily be off. In a perfect world, your frets will be exactly 90* to the centerline going from the tailblock to the center of the fingerboard. However, it is very easy to have the actual neck block not 100% square to the centerline in the mold when you assemble the box. So you can get that discrepancy in your picture if the frets are square to the line but the block is not. To me, that looks like what is happening.

I've seen it happen a lot lot lot.

If that's what it is, I wouldn't worry about it at all, just try to do better on the next one...

Are you sure the top is centered on the sides........???

Tom
I see Dave White has pointed this out...............given that I agree with his take on the problem. I'm slow on the draw today....!!!

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A person who has never made a mistake has never made anything!!!

This isn't at all the same problem I had so my input is void... Mine was just skewed to the treble side but everything was square. Something is clearly not square on yours. If I were to guess I would have to say the fretboard is skewed on the neck but you probably could correct it with the placement of the saddle or bridge.

But that is only a guess since i have only built one guitar. I will leave the knowing to those that do know...

Bob

Track it down one point at a time. Make sure the top is centered on the body. Make sure the neck is centered on a line through the body (I suspect your initial problem was just more finish build up on one side of the body than the other right at the neck joint). If those things check out, I suspect a fret board that shifted during glue up. They seem to want to do that. For what it's worth, I don't think you need to make a new neck at all, but you might consider a new finger board. I know it's a pain, but it's not the end of the world.

I agree with meddlingfool, you need to determine if the frets are perpendicular to the centerline of the neck by
measuring from the nut to the treble and base sides of the 12th (or whichever) fret. Your second picture suggests
that they may not be. If they are not, I'd replace the fretboard, or build a new neck if you can't get the board off.
If they are correctly placed, then I'd split the difference by sliding the bridge 1/2 of your difference off, then placing
the saddle off the remaining distance.

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Gene

Politicians and diapers must be changed often, and for the same reason- Mark Twain

How's the intonation? Does it play ok? If the answer is yes I agree with that meddling fool. Let it go and do better next time. Just my 2 cents

I don't believe it's complete yet...

Guys thank you all again for your advice, I have a very quick check on my way out the door to work this morning to make sure that frets are perpendicular to the centre line of the fretboard again and it looks fine, though I will double check this tonight when I have more time. I am going to go over all of the recommended steps and check everything out but i am guessing that it is either the fretboard slipped during glue up or as Dave mentioned that the body is asymmetric. Ill report back later.

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Nick

Follow my musings on getting started in luthiery http://www.tredwellinstruments.co.uk

So last night I checked things over.

The frets are defiantly perpendicular the the centre line of the fretboard.

The centre line of the body and fretboard line up.

It would therefore appear that either the body is not symmetrical or the fretboard slipped during glue up. Either way I don't think its a deal breaker just cosmetic. I think I will continue and get her finished and strung up and see what happens.

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Nick

Follow my musings on getting started in luthiery http://www.tredwellinstruments.co.uk

Is the top surface of the guitar perpendicular to the center line of the guitar? I agree that I think you are fine and will not be noticeable unless you point it out.

It is a beautiful guitar. Not to hijack the tread but what is the purling made of. What did you use for the black lines? It looks great. I did something very similar on my current build. I hope mine looks that good.

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EddieLee

Thanks Eddie the puddling is black veneer not sure what it is as I was given it but think it is dyed sycamore or similar and mahogany which was left over from the sides. I glued this up as a sandwich and cut strips.

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Nick

Follow my musings on getting started in luthiery http://www.tredwellinstruments.co.uk