Official Luthiers Forum!

Owned and operated by Lance Kragenbrink
It is currently Mon Aug 04, 2025 1:43 pm


All times are UTC - 5 hours


Forum rules


Be nice, no cussin and enjoy!




Post new topic Reply to topic  [ 16 posts ] 
Author Message
PostPosted: Tue Nov 10, 2009 10:50 am 
Offline
Koa
Koa
User avatar

Joined: Thu Feb 28, 2008 11:45 pm
Posts: 730
Location: Lincoln, NE
First name: Paul
Last Name: Burner
City: Lincoln
State: Nebraska
Zip/Postal Code: 68506
Country: United States
Focus: Build
Status: Amateur
I've hit a small problem in my current build and thought I'd get your input about what to do if you don't mind.

The guitar my son and I are building has a florentine cutaway - the first one we've ever done. I thought I had measured everything properly for the neck alignment - but the neck doesn't perfectly line up with the flow of my cutaway when I test bolt it to the body. It is possible that there is a problem with the size of the cutaway insert on my mold that all measurements were based off of - but I thought I had even checked all that. Anyway... the neck/fingerboard will overlap about 1mm+. That doesn't sound like much - but it is a good amount when everything is aligned.

I see that I have a couple options - but you may have others for me.

Here's what I'm considering:

1) Just change (sand) the taper of the neck/fingerboard to fit the body and see how things fall on the string spacing at the bridge. If things don't look right, I could try option #2.

2) Use a different bridge along with changing the taper of the neck/fingerboard. The bridge I intended to use was for a string spacing of 2.25". I could go with a more standard 2.125" spacing and adjust the neck taper a bit to make it fit to the body.

3) Since the amount I'm off is minimal, I could route the mortice channel a little bit wider allowing me to slide the neck over that 1mm. Or - I could trim off 1mm from one side of the tenon allowing the same movement of the neck. Either of these would put the neck slightly off center to the body.

I'd appreciate your thoughts/comments.

_________________
P A U L B U R N E R
Burner Guitars


Top
 Profile  
 
PostPosted: Tue Nov 10, 2009 11:44 am 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Tue Jan 04, 2005 10:03 am
Posts: 6680
Location: Abbotsford, BC Canada
Hi Paul,

My first guitar had a cutaway and I wanted a flush fit between the neck and body. Well I didn't get it right and I had an overlap of about 1mm. I decided to sand the fretboard and neck to flush it up with the body. That was a bad idea as it always stuck out to me. Very noticable.

I think Option #2 is what you want to do. 1mm is just over 1/32" so you'll need to change the width of the fretboard at the 12th by 1mm each side (2mm overall) and if you can lay that out at the 14th fret (assuming it's a 14 fret joint) I think you'll be able to get away with a 2 3/16" pin spacing on the bridge.

So just taper the fretboard, leaving the nut alone and adjusting the rest.

_________________
My Facebook Guitar Page

"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson


Top
 Profile  
 
PostPosted: Tue Nov 10, 2009 11:52 am 
Offline
Koa
Koa
User avatar

Joined: Sat Mar 07, 2009 7:56 am
Posts: 1825
Location: Grover NC
First name: Woodrow
Last Name: Brackett
City: Grover
State: NC
Zip/Postal Code: 28073
Country: USA
Focus: Build
If I'm understanding your problem correctly I'd just move the neck toward the bass side 1mm. You can even angle it a little so the bridge will still be centered.

_________________
I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/


Top
 Profile  
 
PostPosted: Tue Nov 10, 2009 11:52 am 
Offline
Cocobolo
Cocobolo
User avatar

Joined: Sat Oct 21, 2006 7:07 am
Posts: 280
Location: United States
There is nothing magic about having your bridge absolutely dead-center. If you can shift the lateral position a bit without dramatically changing how it will sit over the braces, I would chose that option. You can easily be off-center by 1/4" before it will be visually noticeable.

Been there, done that-with my first Florentine, I might add.... it turned out just fine [:Y:]

_________________
It's not the miles ahead, it's the stone in your shoe


In Markham,Virginia


Top
 Profile  
 
PostPosted: Tue Nov 10, 2009 12:00 pm 
Offline
Koa
Koa
User avatar

Joined: Thu Feb 28, 2008 11:45 pm
Posts: 730
Location: Lincoln, NE
First name: Paul
Last Name: Burner
City: Lincoln
State: Nebraska
Zip/Postal Code: 68506
Country: United States
Focus: Build
Status: Amateur
Rod,

Thanks for the reply. I am not going to change the 1.75" width at the nut - but only the angle of the taper to narrow the neck at the higher frets to make it fit the body better. Any suggestions on how to pull this off? I was thinking of clamping the fingerboard to a shooting board with the overhang being what I need to remove.

In my Option #1 stated above (and #2 for that matter), I am planning on doing the change to both sides of the neck to make it still look symmetrical.

The only difference in what I'm intending between #1 and #2 is a different bridge as I had already made one based on the 2.25" string spacing.

- - - - - - - - - - - - - - - -

Woody & Jon,

Thanks to you also. I will definitely consider this option as I don't have to mess with the neck/fingerboard that are pretty much ready to go.

_________________
P A U L B U R N E R
Burner Guitars


Top
 Profile  
 
PostPosted: Tue Nov 10, 2009 12:03 pm 
Offline
Koa
Koa
User avatar

Joined: Thu Feb 28, 2008 11:45 pm
Posts: 730
Location: Lincoln, NE
First name: Paul
Last Name: Burner
City: Lincoln
State: Nebraska
Zip/Postal Code: 68506
Country: United States
Focus: Build
Status: Amateur
Woody and Jon,

Is there any problem with the tenon not being a snug fit in the mortice on a 2-bolt neck?

I'm asking as I would either have to remove that 1mm+ from the tenon or route the mortice bigger.

I'm leaning towards making the tenon narrower to allow me to slide the neck over the amount I need. Would you see this a problematic?

_________________
P A U L B U R N E R
Burner Guitars


Top
 Profile  
 
PostPosted: Tue Nov 10, 2009 12:10 pm 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Tue Jan 04, 2005 10:03 am
Posts: 6680
Location: Abbotsford, BC Canada
Woody and Jon's suggestion is good.

If I were to do it that way, I'd take it off one side of the tenon and add a shim to the other side of the tenon.

_________________
My Facebook Guitar Page

"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson


Top
 Profile  
 
PostPosted: Tue Nov 10, 2009 12:32 pm 
Offline
Brazilian Rosewood
Brazilian Rosewood
User avatar

Joined: Thu Oct 06, 2005 1:05 pm
Posts: 3350
Location: Bakersville, NC
Focus: Build
Status: Professional
1mm is not a whole lot. I hate misaligned necks. Please don't take me wrong but that shortcut would account for visual poor joinery. Just cut the taper at the 14th fret and be done with it. I bet it may even make a more comfortable neck. If you align the neck center with the tail end seam but the neck is not centered and the neck block your bridge will look out of place and at a slight angle....
But before you do anything make sure the neck is centered. Sometimes the neck is slightly off center and the solution would be just to remove material from the tenon and move it over to the bass side.

_________________
Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com


Top
 Profile  
 
PostPosted: Tue Nov 10, 2009 12:46 pm 
Offline
Koa
Koa
User avatar

Joined: Thu Feb 28, 2008 11:45 pm
Posts: 730
Location: Lincoln, NE
First name: Paul
Last Name: Burner
City: Lincoln
State: Nebraska
Zip/Postal Code: 68506
Country: United States
Focus: Build
Status: Amateur
Peter -

THIS is why I love OLF! I wouldn't have thought about the heel alignment to the back seam of the guitar.... and visually that would have been a problem.

Now I'm back to changing the taper on the neck/fingerboard so it fits!

Thanks!

_________________
P A U L B U R N E R
Burner Guitars


Top
 Profile  
 
PostPosted: Tue Nov 10, 2009 12:48 pm 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Wed Aug 31, 2005 7:30 am
Posts: 1792
Location: United States
I wouldn't touch the fretboard taper, but would remove 1mm of material from the tenon so the FB is flush with the cutaway. Then glue a veneer the same thickness on the other side of the tenon so there's a good tenon/mortise fit. You neck will be slightly off centre at the upper bout, well by 1mm.
Since it's a cutaway nobody will ever notice, you may have to fuss a bit with the end of the fretboard and the rosette.
If you align your neck with the centre of the lower bout, the bridge should be off centre by very little (around 1/2mm). Not unusual at all, as Todd pointed out…

_________________
Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/


Top
 Profile  
 
PostPosted: Tue Nov 10, 2009 1:39 pm 
Offline
Koa
Koa
User avatar

Joined: Thu Feb 28, 2008 11:45 pm
Posts: 730
Location: Lincoln, NE
First name: Paul
Last Name: Burner
City: Lincoln
State: Nebraska
Zip/Postal Code: 68506
Country: United States
Focus: Build
Status: Amateur
Todd Stock wrote:
FWIW, you might measure the distance from body edge to edge of mortise, double that, and add to the mortise width...the sum should be the fretboard width at the body fret if mortise is centered. Compare with the distance from edge of body to center seam...should be the same as 1/2 of 14th fret fretboard width. If not, the mortise is off-center. Also worth checking if the center seam is actually centered before assuming the mortis is spot on. Obviously, also worth checking to see if tenon is centered on the neck as well..


Todd and all....

I am using my standard Almond Point heel on my neck - and not a flat heel. What this means is that there is an obvious visual reference to the center alignment of the heel to the back seam. I have bolted my 5-piece neck in place, and because of the laminations in the neck heel (without the cap yet), I can see that the mortice and neck are perfectly centered to the back seam. So, I suppose the good news is that things are "on center". I am now believing that any movement of the neck to compensate for my Florentine cutaway misalignment will cause a visual problem on the back of the guitar.

It appears that I may need to do the tapering route

_________________
P A U L B U R N E R
Burner Guitars


Top
 Profile  
 
PostPosted: Tue Nov 10, 2009 2:36 pm 
Offline
Brazilian Rosewood
Brazilian Rosewood
User avatar

Joined: Thu Oct 06, 2005 1:05 pm
Posts: 3350
Location: Bakersville, NC
Focus: Build
Status: Professional
Paul Burner wrote:

I am using my standard Almond Point heel on my neck - and not a flat heel. What this means is that there is an obvious visual reference to the center alignment of the heel to the back seam.



This is exactly what I was referring to. If Paul moves the neck away from the edge, then the center of the heel will no longer align with the center of the guitar. 1mm will not be noticeable in the taper and the string spacing may even be left alone.

_________________
Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com


Top
 Profile  
 
PostPosted: Tue Nov 10, 2009 5:50 pm 
Offline
Koa
Koa
User avatar

Joined: Thu Feb 21, 2008 8:57 pm
Posts: 1982
Location: 8.33±0.35 kpc from Galactic center, 20 light-years above the equatorial in the Sol System
First name: duh
Last Name: Padma
City: Professional Sawdust Maker
Focus: Build
Well Paul

You could always try using the neck widner. But me aint seen one of them for decades and wooden't know were in hecks to find one.

Sorry for making light of the situation...sometimes we just gotta laugh at our fumbles...and by the way...me have made this mistake a few times.

Is why me now save final shapeing of the neck till the end, cuz knowin me...me only gonna do it again.

blessings
the
Padma

_________________
.

Audiences and dispensations on Thursdays ~ by appointment only.



.


Top
 Profile  
 
PostPosted: Tue Nov 10, 2009 6:25 pm 
Offline
Koa
Koa

Joined: Thu Jan 24, 2008 2:13 am
Posts: 902
Location: Caves Beach, Australia
Well you have had a lot of good suggestions to which I am only going to add this
- Perhaps you could do a little of everything

eg
-move the neck across 1/2 mm which should not be noticable with the heel cap between
-narrow the neck 1/2mm each side
-check whether the bridge spacing needs modifying


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 16 posts ] 

All times are UTC - 5 hours


Who is online

Users browsing this forum: No registered users and 18 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
Powered by phpBB® Forum Software © phpBB Group
phpBB customization services by 2by2host.com