force exterted on neck

[jakelock]

hi, i need a rough idea of the force that is exerted on a standard bass neck/truss rod, (21 frett, 4 string) any clue would help a lot, cheers

[Mike N]

Hi Jake, welcome to TalkBass.

Force on the neck would depend on a few factors, such as string type & gauge, and standard or drop tuning.

Assuming rounds and EADG tuning, my D'Addario rounds have the following tension.....

E - 36.5 lbs
A - 42.0 lbs
D - 51.3 lbs
G - 42.8 lbs

Now I'm not sure if you would simply add all four #'s together to get the total force exerted on the neck, or if you average the #'s, or what.

[Hambone]

Originally Posted by Mike N

Hi Jake, welcome to TalkBass.

Force on the neck would depend on a few factors, such as string type & gauge, and standard or drop tuning.

Assuming rounds and EADG tuning, my D'Addario rounds have the following tension.....

E - 36.5 lbs
A - 42.0 lbs
D - 51.3 lbs
G - 42.8 lbs

Now I'm not sure if you would simply add all four #'s together to get the total force exerted on the neck, or if you average the #'s, or what.

For this, you would add the figures for the total.

[MikeBass]

Originally Posted by Hambone

For this, you would add the figures for the total.

Umm, sorta.
Doing this is difficult because the force exerted is not at a right angle to the neck, but almost parallel to it. So it isn't as simple as just adding the totals.
I guess for simple discussions it would work.

[Hookus]

Originally Posted by MikeBass

Umm, sorta.
Doing this is difficult because the force exerted is not at a right angle to the neck, but almost parallel to it. So it isn't as simple as just adding the totals.
I guess for simple discussions it would work.

I would imagine it is somewhat less than the sum. But it would be a question more suited for an engineer. As was said above, the force is the string pulling from the bridge to the nut, not the force pulling the neck sideways. The amount of tension on the truss rod is small, since the vast majority of the string tension is absorbed lengthwise as compression on the neck, or compressing about two feet of pretty hard wood. Only a slight amount is applied sideways to the neck because the strings are not pulling through the center of the neck. This is why you can press or pull on the back of the neck slightly for a tremolo type effect. I bet you are applying no more than five or ten pounds of pressure, certainly nowhere near the two-hundredish pounds of string tension.


So, in answer to your question, not much force on the truss rod at all.