Bolt on Mortise and Tenon - Follow up Question

[Nahil.R]

Sorry I wasn't sure how to add this question to my other post so i opted to start a new one.

Thank you all for the advice on making the final adjustments from the tenon side, it worked great.

My follow up question is about the plane between the neck and body joint.

The neck protrudes by just under 1mm over the height of where it joins the body ... The connection should flush shouldn't it?.

What can I do to fix this issue to have a seamless fit?

Any help would be greatly appreciated.

Thanks,

Nahil.

[Skarsaune]

If the neck is protruding 1mm above the sound board, you need to examine the joint for what is interfering.

Two likely suspects are: the bottom of the tenon is hitting the bottom of the mortise pocket, or the bolts are hitting the through hole before the neck is fully seated.

Solutions could include taking a bit off the bottom of the tenon, and opening the bolt holes for a bit more clearance to the bolts.


If the neck is protruding 1mm above the side of the body, your tenon is bottoming out before the heel is contacting the side.


Pictures would be very helpful.

[Nahil.R]

Originally Posted by Skarsaune

If the neck is protruding 1mm above the sound board, you need to examine the joint for what is interfering.

Two likely suspects are: the bottom of the tenon is hitting the bottom of the mortise pocket, or the bolts are hitting the through hole before the neck is fully seated.

Solutions could include taking a bit off the bottom of the tenon, and opening the bolt holes for a bit more clearance to the bolts.


If the neck is protruding 1mm above the side of the body, your tenon is bottoming out before the heel is contacting the side.


Pictures would be very helpful.

Sorry I haven't bothered trying to figure out how to upload photos yet.

You were absolutely right, the tenon was bottoming out ... I removed slithers incrementally and managed to get it to where its meant to be. Thanks for the guidance.

Nahil.

[Neil K Walk]

Do you mean that your tenon is too "tall" for the mortise?

I have been there myself. I am no luthier but here's what I did:

1: chiseled away at the bottom of the tenon so that it is closer/slightly under the length of the mortise. It takes a little "artistry" to match with hand tools but it's not something that I like to trust to power tools like routers that have a tendency to "drift."

2: ream out the holes for the bolts in the neck block to accommodate any change in alignment. There will be "play" in the vertical alignment but the fretboard will act as a "stop" when it comes time to do the final neck installation.

3: use rubber washers against the head of the bolt (inside the body) to absorb any potential shocks.

[Nahil.R]

Originally Posted by Neil K Walk

Do you mean that your tenon is too "tall" for the mortise?

I have been there myself. I am no luthier but here's what I did:

1: chiseled away at the bottom of the tenon so that it is closer/slightly under the length of the mortise. It takes a little "artistry" to match with hand tools but it's not something that I like to trust to power tools like routers that have a tendency to "drift."

2: ream out the holes for the bolts in the neck block to accommodate any change in alignment. There will be "play" in the vertical alignment but the fretboard will act as a "stop" when it comes time to do the final neck installation.

3: use rubber washers against the head of the bolt (inside the body) to absorb any potential shocks.

Thanks for the advice I really appreciate it.

Now I am trying to get the 'cheeks' on the around the tenon to fit flush with the body (flossing away)

I am worried that I may be headed for an issue where the tenon is actually protruding too much to allow the cheeks to rest against the guitar sides then I have no idea what to do! the bolt insets are not set very deep in the tenon so theres not much room for wood removal the? Maybe I will need to try and add some depth on the mortise itself so it has room to accommodate the tenon.

Anyone have any advice what the best course of action would be?

Thanks,

Nahil.

[Neil K Walk]

Originally Posted by Nahil.R

Thanks for the advice I really appreciate it.

Now I am trying to get the 'cheeks' on the around the tenon to fit flush with the body (flossing away)

I am worried that I may be headed for an issue where the tenon is actually protruding too much to allow the cheeks to rest against the guitar sides then I have no idea what to do! the bolt insets are not set very deep in the tenon so theres not much room for wood removal the? Maybe I will need to try and add some depth on the mortise itself so it has room to accommodate the tenon.

Anyone have any advice what the best course of action would be?

Thanks,

Nahil.

I came up against that as well. I ended up taking a rasp and file to the end face and whittling away at the mass of both wood and steel. Things got quite hot!

Moving forward, it's always best to design a 1/8" difference between the depth of the mortise and the "height" of the tenon. It's also a good idea to save the "flossing" for the fine tuning of the angle and use a rigid file for when you have to be more aggressive in removing material.

BTW, I also struggle with keeping things visually centered. I made the mistake of carving my neck before setting the angles. Next time I build a guitar from scratch I will be gluing the fretboard to the unfinished blank and then carving afterwards so that I have a better reference when setting the angle.