Neck Angle

[mr smits]

Hey all,

This applies to an electric guitar I'm finishing up. It needs a shim in the pocket, and I'm deciding between a .5 and .75 degree shim. The .75 seems to feel better and play better, but the strings get this upward curve near the neck pickup where they almost banana up toward the bridge.

My questions are: is this normal? My concern is the .75 degree shim might be putting torque on the neck and warp it over time. Is this a legitimate concern, or is only an aesthetic issue? Is a curve near the bridge pickup up toward the bridge okay?

I hope this makes sense. Hard to explain...!

Thanks!

[Greg Mirken]

No; does not make sense. I can't imagine any way a tapered shim in the neck pocket could induce a curve anywhere.

[mr smits]

Using "it" was a bad idea. I rewrote the sentence:

the strings get this upward curve near the neck pickup where they almost banana up toward the bridge.

[mr smits]

Also, when bending strings, there is more tension with the .75 degree shim. Would this due to more downward pressure on the bridge? It's pretty annoying the amount of tension! Makes the guitar feel stiff instead of buttery.

[Taffy Evans]

Hi, maybe I'm not understanding this properly, but, I would think that the strings would always be straight or flat, if under tension. The pull of the magnet in a pickup can affect the movement of a string, if too close. It would have to be pretty strong to pull the strings into a banana-like curve.

Changing the neck angle would change the break angle of the strings over the bridge saddles, I would have thought, and in turn, increasing or decreasing downward pressure on the saddles and the stiffness "feel" of the strings.

Just a thought Taff.

[mr smits]

It's hard to explain, and it might even be an optical illusion. But it's like this image:

https://www.mylespaul.com/attachments/firebird-taper-jpg.469867/

Basically as the string goes toward the bridge, it appears to curve slightly like a banana.

[Roger Häggström]

Use a long ruler or a non-metal nylon string and see if the strings are straight. If bent, adjust the magnetic pickups further away from the strings.

[Paul Verticchio]

If the neck has fall away engineered into the highest frets (14-22) it MAY create the optical illusion of curved strings to the novice or inexperienced tech.

I’ve not experienced that in 40+ years in the craft.

The laws of physics will not allow a motionless and “uninfluenced” string under proper tension to bend as described.

[Russell Vance]

Thanks Paul,

I was just about to say that - its not the string that is bent and eyesight/glasses or illumination may be influencing what appears to you.    This rabbit has gone way too far down the rabbit hole.  Check your skinnys:  10 -17 which aren't affected at all by the pickup magnetic pull and you'll get the picture.  Anyway, back off yr pickups and have a look if you are still not convinced.   After that, you need to start looking for things like "ski slope" takeoff at the end of the FB or 14th fret "kink" (a Fender specialty) and a whole bunch of other stuff that cannot be corrected with a shim or a neck angle adjustment screw ( a fashion accessory on most Fenders that have them).

Adjustment of saddle heights on "standard"  string through (think Strats or Tele's) within a 20/40 thou bandwidth are unlikely to do much to the actual 'stiffness' of the action ( some may disagree here but I don't care much as the physics and geometry beats out perception every time),  String height above the fret will.  Also floating the trem will, etc etc. 

Try to think of the neck as three positions in space, not related to the body:  The nut, the bridge saddles and the 22nd fret  and then introduce the various string ellipses subscribed from the first to (roughly) the 15th fret into this system.  The effect of the truss rod is only over the first 12 - 15 frets as well, so don' t get sucked into thinking the ski slope over the last 10 frets can be influenced by the rod.  

These are a few things that greatly influence whether an electric will play or feel good and these days we are more likely to "drop away" the frets from the 15th onwards rather than bother with fiddling with truss rod and action adjustment on necks that are past their use by date. 

Hope this helps, and Paul and I have around 70 years of doing this stuff and will eventually get get good at doing it ( and explaining it). 

Regards. 

Rusty.