Neck angle

[vinceg]

Hi, how do you calculate the neck angle? Is the Tundraman calculator reliable or is need other factors like string action?
http://www.tundraman.com/Guitars/NeckAngle/index.php

[mistermikev]

disclaimer: I have no idea.  New builder here and wondering much the same... perhaps if I bump you one of these kind and knowledgeable folks will chime in.  

Here's what I have read so far...pretty much everyone is going to tell you that the only reliable way to do this is to layout your specific items on paper.  Since it is the year 2018 I'd say as long as you take a calipers and measure you could do this more accurately in a graphics program.

 

my guess is you could lay things out on a flat plane, then see how far off your bridge would be.  that distance is your 'rise' and your scale length is your run.  rise/run = slope. 

then figure out the length of contact in your neck pocket... that is the adjacent and we probably want to know the height of the opposite or "what is the armount of rise in that neck pocket from front to back) so... tan(slope) = opp / adjacent

adjacent * (tan(slope)) = opposite.

 

there are probably better explanations and perhaps easier methods so perhaps my sloppy explanation will invoke them.

 

[komodo]

Most builders will not even start a build until they have the actual bridge in hand. You must already know what scale length you will use. Nothing beats an actual full scale drawing, even if it's just a side view of the intersecting planes much like the drawings on the tundraman site mentioned. Don't overlook the fact that you bridge will have some adjustment to it, but don't rely on the adjustment to reach your height. Try to hit your optimal arrangement but with a little adjustment up AND down so you can fine tune it. Hope this makes sense.

[Andyjr1515]

On 5/12/2018 at 12:19 PM, vinceg said:

Hi, how do you calculate the neck angle? Is the Tundraman calculator reliable or is need other factors like string action?
http://www.tundraman.com/Guitars/NeckAngle/index.php

I agree with @komodo

There is nothing wrong from a trigonometrical point of view with Tundraman's calculator, but there are a lot of areas where, in practice, things can be a little bit different and the cumulative effect is dramatic.

Almost all of my builds are through-necks and I always - as @komodo says - make sure I have the bridge and fretboard blank in my possesion and the planned fretwire dimensions first. 

I'm sure there are better ways than I do it, but basically I draw the critical points full size.  It only needs a few lines drawn with a decent length steel rule.  The critical thing is knowing how much practical saddle adjustment is available to start with.

Probably more drawing than actually needed (but it helped me also envisage how deep the pickups needed to sit) but here is one of my drawings:

 

In the above photo:

 

Trust me - it's quicker to draw it than to explain it!

• the hatched fretboard represents the total height of the fretboard and frets combined. 
• The pivot point - as Tundraman says, this is the point at which the neck joins the body - can be seen as the dot a few inches to the right of the fretboard end
• The line broken by dots at the very top is the string, giving me the required action height target at the fretboard end and originating at fret height only at the nut
• the short line on the left hand side with the writing next to it is where the top of the saddle needs to be at its lowest adjustment position (sitting below the string line a touch to give me a 1mm or so wiggle room)
• The full line immediately below it is the 'zero angle' line, parallel with the tops of the frets
• The ^ at the left hand side is at the scale length and, vertically, is where the bottom of the bridge (ie the top of the body) needs to be
• Joining a line from the ^ to the pivot point, gives me the required neck angle

[komodo]

Another thing is that when you do this exercise, you will be able to visualize the geometry of the guitar better. Doing topdown drawings, or even 3D CAD stuff only gets you so far. Nothing beats the real world experience of the ACTUAL angles on paper, or in the case of the body size and shaping, a full sized mockup to hold in your lap and see how it feels. Hell, even a flat cutout of cardboard is better than nothing for that.