Neck blank prep -tenor

ChuckBarnett

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2nd build and trying to improve myself.

Doing a practice neck to refresh my memory (it's never been particularly good and lately it's not getting better!). The 3 different woods I will be experimenting with are mahogany --Philippine, African (Khaya), and Genuine (Honduran?) are all 7/8" or heavier. I built this practice neck from stuff I thicknessed down to 3/4" but it sure looks heavy. Bob Gleason says I should get the thickness close to working dimensions before doing the scarf joint.

Okay, here's the question: What do you shoot for in terms of thickness to get to the stage I am with this practice neck? And, perhaps, why that dimension?

Trying to not be nearly the pest I was with the first build...

Chuck Barnett
 

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For a tenor, depending on how much final shaping I want to do, I usually aim for a head stock thickness of ~12mm, a raw neck thickness of 14 -15mm at the first fret, and 17-18mm at the tenth fret.
Dressing can reduce these figures by ~1mm or so.
I cut the scarf at 19mm, which is the local DAR dimension of a standard quartersawn board.
For plain or unattractive head stock grain, I add a 0.6mm face veneer.
Some experienced players have rigid preferences for neck depth and profile, but thankfully, ukulele players are generally less pedantic than guitarists.
Consider a few opinions before deciding what your approach should be … non-ergonomic necks can impact on the appeal of otherwise well-built instruments.
 
For a tenor, depending on how much final shaping I want to do, I usually aim for a head stock thickness of ~12mm, a raw neck thickness of 14 -15mm at the first fret, and 17-18mm at the tenth fret.
Dressing can reduce these figures by ~1mm or so.
I cut the scarf at 19mm, which is the local DAR dimension of a standard quartersawn board.
For plain or unattractive head stock grain, I add a 0.6mm face veneer.
Some experienced players have rigid preferences for neck depth and profile, but thankfully, ukulele players are generally less pedantic than guitarists.
Consider a few opinions before deciding what your approach should be … non-ergonomic necks can impact on the appeal of otherwise well-built instruments.

Thanks for taking the time to help me with my question. I'll work on getting my head around what you have given me here. 😃
 
For a tenor, depending on how much final shaping I want to do, I usually aim for a head stock thickness of ~12mm, a raw neck thickness of 14 -15mm at the first fret, and 17-18mm at the tenth fret.
Dressing can reduce these figures by ~1mm or so.
I cut the scarf at 19mm, which is the local DAR dimension of a standard quartersawn board.
For plain or unattractive head stock grain, I add a 0.6mm face veneer.
Some experienced players have rigid preferences for neck depth and profile, but thankfully, ukulele players are generally less pedantic than guitarists.
Consider a few opinions before deciding what your approach should be … non-ergonomic necks can impact on the appeal of otherwise well-built instruments.

Based on what you suggest I think that the 3/4" thickness (~19 mm) for the blank is ballpark. The numbers to shoot for at various fret locations is down the road from what I was looking for, but certainly useful. My headstock veneer will be thicker since I'll have inlay on it.

My difficulties last time were about getting the nut location, 14th fret location and peghead thickness to come together. If you plane the headstock the distance from nut to 12 and 14 frets is pushed further out. Conversely, if you plane the top of the neck that distance grows longer. After that battle I decided for future building to forget things downstream and establish the nut location and thickness the back side of the headstock. Then work the rest out. It might be helpful for me to see what the methods are others use who actually know what they're doing with this process.
 
My difficulties last time were about getting the nut location, 14th fret location and peghead thickness to come together. If you plane the headstock the distance from nut to 12 and 14 frets is pushed further out. Conversely, if you plane the top of the neck that distance grows longer. After that battle I decided for future building to forget things downstream and establish the nut location and thickness the back side of the headstock. Then work the rest out. It might be helpful for me to see what the methods are others use who actually know what they're doing with this process.

Exactly... If you want to decrease your headstock thickness without disturbing the nut location you can sand down the back of the headstock. Obviously if your nut location on the neck gets shorter or longer, you have changed the location of the bridge longer or shorter in order to comply with your calculated scale length. This may move the bridge out of that "sweet-spot" location. Hope that helps. Of course you could change your scale length and fret interval to compensate and keep the same bridge location, but that is bit like the tail wagging the dog so to speak.
 
Exactly... If you want to decrease your headstock thickness without disturbing the nut location you can sand down the back of the headstock. Obviously if your nut location on the neck gets shorter or longer, you have changed the location of the bridge longer or shorter in order to comply with your calculated scale length. This may move the bridge out of that "sweet-spot" location. Hope that helps. Of course you could change your scale length and fret interval to compensate and keep the same bridge location, but that is bit like the tail wagging the dog so to speak.

Thanks for responding!

As I recall the issue of where I would end up with the bridge was of concern with that first build. I ended up adding a thin strip to the front of the bridge plate because I wasn't sure I liked where things would line up. (Clearly, that wasn't the best solution, but it's what I did at the time.)

I don't like that sort of situation. Hence my goal is to not be flying by the seat of my pants so to speak but think this stuff through more intentionally.

So I asked lots and lots of questions. Like I said I may not be fast but I sure am slow!
 
Placement of the bridge on the top is absolutely critical to the way the instrument will sound. Too far back and it will sound plinky. Too far forward and it will sound flabby. Determining this spot is what qualified acoustic instrument designers do. I am not a qualified instrument designer myself so I do what most people do and use a template from a reputable designer (whoever that might be - (Lloyd Loar where are you??? Dead I think). So I use Stew-Mac's old tenor template and it yields a fine sounding instrument. Their new tenor template below:

Fullscreen capture 422020 121742 PM.jpg

Note that measurements are not included on this template. I use a much older one that included all the critical measurements. However you can calculate where the center of the bridge plate should be by knowing the the measurement of the entire top from butt end to neck end which is exactly 12 inches. Measure the template (any size it doesn't matter) and determine the center of the bridge plate as a ratio of 12 inches.

Hope that isn't as clear as mud.
 
A few additions to the previously mentioned points:
The accurate placement of the nut (departure point) is necessary in preventing you from having to make further (ad hoc) scale adjustments.
After truing the neck and peghead face surfaces, mark the desired position of the nut accurately with two fine knife lines and do all subsequent measuring/positioning from the lower line. You will then be able to position, trim and shape the heel blocks roughly, before gluing them on. This is providing that your chosen heel block design does not include a stiletto tip, as you will need to leave enough surface area for even clamp force distribution. This tip from the 'School of Lazy Lutherie' negates a bit of rough carving and chisel work, but not the fun shaping bit.
If you intend to 'sink' the nut slot, do not do it until after the fret locations are marked out and checked for accuracy, as the nut slot position will then be difficult to relocate ... (it's OK to ask me how I know this to be worthwhile advice). Ukulele builders may not be bothered with this step, as it is a guitar 'carry-over' and requires a deeper nut.
You can then use a small block plane, Safe-T-Planer or thickness sander to complete whatever work you deem necessary to the back of the peghead, without changing any critical geometry.
If you choose to plane, check regularly to ensure that you are not 'wedging', as that can become an exercise in see-sawing that can result in removing too much wood.
If you opt for the quicker mechanised methods, ensure that you don't overrun and leave insufficient wood for a strong and smoothly shaped transition.
 
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Placement of the bridge on the top is absolutely critical to the way the instrument will sound. Too far back and it will sound plinky. Too far forward and it will sound flabby. Determining this spot is what qualified acoustic instrument designers do. I am not a qualified instrument designer myself so I do what most people do and use a template from a reputable designer (whoever that might be - (Lloyd Loar where are you??? Dead I think). So I use Stew-Mac's old tenor template and it yields a fine sounding instrument. Their new tenor template below:

View attachment 126235

Note that measurements are not included on this template. I use a much older one that included all the critical measurements. However you can calculate where the center of the bridge plate should be by knowing the the measurement of the entire top from butt end to neck end which is exactly 12 inches. Measure the template (any size it doesn't matter) and determine the center of the bridge plate as a ratio of 12 inches.

Hope that isn't as clear as mud.

Helpful as always, Sequoia! Thank you for the template concept. When I put that first one together I made sure that I was following the plan for scale length, etc. That's why I was concerned that I might have to redo the neck which I had put some time into. I am making a coupleneck templates.
 
A few additions to the previously mentioned points:
The accurate placement of the nut (departure point) is necessary in preventing you from having to make further (ad hoc) scale adjustments.
After truing the neck and peghead face surfaces, mark the desired position of the nut accurately with two fine knife lines and do all subsequent measuring/positioning from the lower line. You will then be able to position, trim and shape the heel blocks roughly, before gluing them on. This is providing that your chosen heel block design does not include a stiletto tip, as you will need to leave enough surface area for even clamp force distribution. This tip from the 'School of Lazy Lutherie' negates a bit of rough carving and chisel work, but not the fun shaping bit.
If you intend to 'sink' the nut slot, do not do it until after the fret locations are marked out and checked for accuracy, as the nut slot position will then be difficult to relocate ... (it's OK to ask me how I know this to be worthwhile advice). Ukulele builders may not be bothered with this step, as it is a guitar 'carry-over' and requires a deeper nut.
You can then use a small block plane, Safe-T-Planer or thickness sander to complete whatever work you deem necessary to the back of the peghead, without changing any critical geometry.
If you choose to plane, check regularly to ensure that you are not 'wedging', as that can become an exercise in see-sawing that can result in removing too much wood.
If you opt for the quicker mechanised methods, ensure that you don't overrun and leave insufficient wood for a strong and smoothly shaped transition.

Bazuku, you filled in some big gaps in answering my next question! I was stumbled on how the process should flow and now I see I'm on track after all. I have trued the two top surfaces (belt sander is my friend!) and felt that the next logical step was to set the nut location. And you confirmed that!

I am aware that the Safety Planer can get away from you -My first headstock veneer was double thickness because I wasn't proficient with it.

Very grateful! And grateful for this forum, as always.
 
I have trued the two top surfaces (belt sander is my friend!) and felt that the next logical step was to set the nut location.

Chuck,
The belt sander is a real time saver.
However, I'm always cautious to the point of checking any critical surfaces that come off mine with a straight edge... they're usually fairly good, but can sometimes show a bit of waving.
Neck face and peg head surfaces get a few well-aligned passes across a self adhesive 220 grit sheet, stuck to the machined surface of a cast iron saw table. I scribble light pencil lines across the face and sand until they fade. This must be done with the piece held dead flat (zero rocking). I used to run them across a bench planer (guitar), but for ukulele, this method seems more than adequate, and is less of a threat to the finger tips.
If they're at all rough you'll get a thick glue line... not a huge deal, but so easily avoided.


Have you had a look at Graham McDonald's Ukulele book? It is well laid out for sequential work flow, and is well worth the price for anyone interested in ukulele construction. There is a print version as well as an ePub version for immediate download. There is (was?) also a free chapter to assess.
 
Chuck,
The belt sander is a real time saver.
However, I'm always cautious to the point of checking any critical surfaces that come off mine with a straight edge... they're usually fairly good, but can sometimes show a bit of waving.
Neck face and peg head surfaces get a few well-aligned passes across a self adhesive 220 grit sheet, stuck to the machined surface of a cast iron saw table. I scribble light pencil lines across the face and sand until they fade. This must be done with the piece held dead flat (zero rocking). I used to run them across a bench planer (guitar), but for ukulele, this method seems more than adequate, and is less of a threat to the finger tips.
If they're at all rough you'll get a thick glue line... not a huge deal, but so easily avoided.


Have you had a look at Graham McDonald's Ukulele book? It is well laid out for sequential work flow, and is well worth the price for anyone interested in ukulele construction. There is a print version as well as an ePub version for immediate download. There is (was?) also a free chapter to assess.

As I recall, what I did last build was to put sandpaper on a piece of stone countertop that is actually flatter than my tablesaw table. Then I ran the neck across that in a similar fashion. Thanks for the reminder!

I got a different drill press (replaced the 1949 Craftsman) from when I built that first uke and realized that to use that Safe-T-Planer safely I would need to build a wooden table around the round cast iron table it came with. That and other things have kept me away from this build lately.

Never heard of that book, but I will look that up!

Cannot thank you enough!
 
What do you shoot for in terms of thickness to get to the stage I am with this practice neck? And, perhaps, why that dimension?



I work it at full thickness, including the scarf joint, which is usually 3/4”+, depends if I laminate the neck heel or not (usually I do). This measurement, plus 3 x 1/16” heel laminations put the neck heel right about the 2 1/2” heel block I use, minus the radius, plus the top and back. Basically, the thickness is based on the added up stacked neck heel.

I cut the scarf at full thickness, for a couple of reasons. Gluing surfaces are flat from the clean cut on the sliding miter saw. Ok, that’s the main reason. Doesn’t hurt that the joint is covered by a back strap. And, I have a volute, which is the other main reason.

Here’s a scrap neck that I keep to remind me of some stuff, a profile template to rough-in, and a neck in the finishing process.
4BAAE83B-19FC-47DE-93B1-A00AA1BFE5D3.jpg
 
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I work it at full thickness, including the scarf joint, which is usually 3/4”+, depends if I laminate the neck heel or not (usually I do). This measurement, plus 3 x 1/16” heel laminations put the neck heel right about the 2 1/2” heel block I use, minus the radius, plus the top and back. Basically, the thickness is based on the added up stacked neck heel.

I cut the scarf at full thickness, for a couple of reasons. Gluing surfaces are flat from the clean cut on the sliding miter saw. Ok, that’s the main reason. Doesn’t hurt that the joint is covered by a back strap. And, I have a volute, which is the other main reason.

Here’s a scrap neck that I keep to remind me of some stuff, a profile template to rough-in, and a neck in the finishing process.
View attachment 126289

Thanks!!

I remember something someone said early on about this stuff --that there are many ways to get it done. Indeed!

Based on what I'm seeing in the pics, a volute is some sort of ridge between the neck proper and the headstock. Why do you do this? Is there a preference?

I actually thought of heel laminations but haven't gotten that far. Still trying to get closer to the LMI plan for overall body depth at the heel. I'd think it would be eye-appealing to aim for equal segments in the heel. Is the lamination material the same as the heel camp and the fretboard binding? Looks great!
 
Thanks!!

I remember something someone said early on about this stuff --that there are many ways to get it done. Indeed!

Based on what I'm seeing in the pics, a volute is some sort of ridge between the neck proper and the headstock. Why do you do this? Is there a preference?

I actually thought of heel laminations but haven't gotten that far. Still trying to get closer to the LMI plan for overall body depth at the heel. I'd think it would be eye-appealing to aim for equal segments in the heel. Is the lamination material the same as the heel camp and the fretboard binding? Looks great!

There are many ways to do things, and I used to scarf at final thickness when I didn’t have a volute or a back strap. I tried to put the scarf joint at the bend so the joint “bends”. You asked not only for dimensions, but why, right?

I do a volute for a number of reason, mostly as a feature at this point. Visually, I like the transition between the back strap. Also, this is one of those solutions that address other issues, like strengthening the joint at its thinnest point.

The worst thing about neck heel laminations is the shape has to be even in all dimensions.
The best thing about neck heel laminations is the shape has to be even in all dimensions. Took me years to add that in.
Yes, the material is the same as the heel cap, and generally, lately, its the same as all of the bindings, including my radial rosette - Koa, on all my instruments (even Koa). But that’s another story.

Hope this helps.
 
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