Neck projection error

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lamanoditrento
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Neck projection error

Post by lamanoditrento » Tue Jun 20, 2017 1:35 pm

Hi All,

I recently closed the box on a small scale classical (604mm) and while waiting for binding glue to dry and popped a straight edge on the neck and to my horror found the neck projection instead of being negative was positive with a projection at scale length of 3mm.

Turns out that it doesn't matter if you carefully plane and sand a forward relief on the neck of the solera if you don't actually clamp down the neck while closing the box :oops:

So now with the 6mm fretboard, frets at 1mm and a 3mm action at the 12th making another 6mm at scale: I have a projection of 16mm. Approximately 5mm above the combined 8.5mm bridge & 2mm saddle height above the bridge I had intended.

The obvious answer would be to reduce the fretboard heigh at an angle from nut to the soundhole from 0 at the nut to 2mm at the 12th, right? Well the added complication is that I have already slotted and put a compound radius already on the fretboard (yes the one I fretted so much about on another thread).

So do I make a complicated jig for the radiused fretboard to sit upside down in to the drum sander at an angle or there something else I can do?

Would love to hear any suggestions, help or advice.
Trent

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kiwigeo
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Re: Neck projection error

Post by kiwigeo » Tue Jun 20, 2017 1:39 pm

Glue on the fretboard and then plane the neck and then re-radius and deepen or re-cut the slots?? Alternately make up a Gore style "wedge" to slip between the fretboard and neck.
Martin

simso
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Re: Neck projection error

Post by simso » Tue Jun 20, 2017 2:26 pm

Why not just pop the neck of cut and refit the neck (basically a neck reset)

Just out of curiosity why 8.5mm thick bridge, thats a little on the low side.

When I do a neck reset, I aim for about 1/2 inch clearance of strings to the body, I also replace the bridge if someone has been shaving it down to try and avoid having the neck reset.

Steve
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Re: Neck projection error

Post by Jeremy D » Tue Jun 20, 2017 2:57 pm

simso wrote:
Tue Jun 20, 2017 2:26 pm
Why not just pop the neck of cut and refit the neck (basically a neck reset)

Just out of curiosity why 8.5mm thick bridge, thats a little on the low side.

When I do a neck reset, I aim for about 1/2 inch clearance of strings to the body, I also replace the bridge if someone has been shaving it down to try and avoid having the neck reset.

Steve
Can you do that with a Spanish heel?
Jeremy D

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kiwigeo
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Re: Neck projection error

Post by kiwigeo » Tue Jun 20, 2017 2:59 pm

simso wrote:
Tue Jun 20, 2017 2:26 pm
Why not just pop the neck of cut and refit the neck (basically a neck reset)
I think he's built using Spanish method...a neck re-set will require popping the back off, shimming the Spanish foot and then re-attaching the back.
Martin

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Re: Neck projection error

Post by simso » Tue Jun 20, 2017 4:16 pm

Had not clicked he had a spanish heel.

Thats not a good option, I would then shave the fretboard down.

Steve
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Trevor Gore
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Re: Neck projection error

Post by Trevor Gore » Tue Jun 20, 2017 6:52 pm

kiwigeo wrote:
Tue Jun 20, 2017 1:39 pm
...Alternately make up a Gore style "wedge" to slip between the fretboard and neck.
If you do the wedge, you also have the head/neck shaft transition to consider, too. However, if your grain matching and glue lines are good, it's probably the neatest way out.

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Re: Neck projection error

Post by blackalex1952 » Tue Jun 20, 2017 7:32 pm

Trevor, can you clarify what you mean by the
head/neck shaft transition
please? -Ross
"Everything I say on the topic is based solely upon inexperience and assumption!"

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kiwigeo
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Re: Neck projection error

Post by kiwigeo » Tue Jun 20, 2017 9:12 pm

blackalex1952 wrote:
Tue Jun 20, 2017 7:32 pm
Trevor, can you clarify what you mean by the
head/neck shaft transition
please? -Ross
On Trevor's classicals he takes care of the positive neck rake by inserting a long wedge shaped piece of wood between the neck and fretboard (thick end of wedge at headstock). At the headstock end of the neck allowance must be made for the presence of the wedge.
Here's a pic of one of my Gore classicals showing the end of the wedge projecting out from under the fretboard.
IMG_0280.jpg
In this pic the end of the wedge has been trimmed flush with the face of the headstock before application of the headstock veneers. Ignore the MDF routing template stuck on top of the headstock veneers.
IMG_0297.jpg
Martin

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Re: Neck projection error

Post by johnparchem » Wed Jun 21, 2017 12:52 am

The wedge should work body-wise as the the top follows the neck with a Spanish heel construction. I think the issue will be the length of the neck as it has to take into account the wedge becomes part of the peg board. See Martin's picture. The wedge, nut position, nut width and peg head veneer transition would need to be worked out. A bit difficult when laying out up front.

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Trevor Gore
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Re: Neck projection error

Post by Trevor Gore » Wed Jun 21, 2017 9:50 am

blackalex1952 wrote:
Tue Jun 20, 2017 7:32 pm
Trevor, can you clarify what you mean by the
head/neck shaft transition
please? -Ross
What they ^^^ said!

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lamanoditrento
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Re: Neck projection error

Post by lamanoditrento » Thu Jun 22, 2017 8:31 am

Thanks All!

I will start thinking about a wedge.
simso wrote:
Tue Jun 20, 2017 2:26 pm
Just out of curiosity why 8.5mm thick bridge, thats a little on the low side.
The guitar is loosely based off the 'Torres 2' designs in Roy Courtnell's book and that is what is on those plans. I assume with such a small body, a reduced bridge height helped with reducing the mass.
johnparchem wrote:
Wed Jun 21, 2017 12:52 am
The wedge should work body-wise as the the top follows the neck with a Spanish heel construction. I think the issue will be the length of the neck as it has to take into account the wedge becomes part of the peg board
Yes as I have already veneered the headstock, I should be able to account for this with a higher nut? I am using planetary tuners so had cut my scarf joint at 15 degrees. Presumably the wedge will change the angle of the strings break but is there anything else I should consider?
kiwigeo wrote:
Tue Jun 20, 2017 1:39 pm
Glue on the fretboard and then plane the neck and then re-radius and deepen or re-cut the slots?
I might leave this as plan B. Good thing I had finalised the inlay design or I would have already done that.
Trent

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