Switching Necks - Changing the Scale

[Runewalker]

Maybe some Nutz can help me on this issue:

On some builds and customizations I have had to trim the neck heel to maintain the proper scale. They have all been conventional 25.5" scale necks. For example, I put an Ibanez 24 fret on an ESP body. The ESP had a fretboard overhang on its 24 fret neck, the Ibanez heel was flush with the fingerboard cap. The ESP was contured like a Stat neck; The Ibanez was square like a Tele. So I had to "make" the overhang with some careful sawing and shape the Strat type conture. No complaints everthing worked wel because I carefully measured form the mid point of the saddles' travel rangeto the nut to reestablish the 25.5" scale. If I had just installed the neck the distance from saddle to nut would have been about 25 7/8".

Ok, I know, get to the point.

The point is I am about to build an exotic hybrid that will irritate the purists. I am taking an SG bolt on body (which already crosses the line for the purists) and adapting a 25.5" scale neck to it. Why? Lets just say I have my reasons.

I have a 24 Fret neck, so I have plenty to work with. Intial measures indicate I will have to cut at either the 22 1/2 fret position or right on the 23 fret. The issue is that SG and Les Pauls have staggered posts for the tuneomatic, ie, the post on the high E is closer to the neck than the post on the low E. Whereas the strat bridge is square to the perpandicular plane of the neck (alright! Geometry!, remember that?)

So the question is:

Where do I start the measurement from to the nut:

• From the low E post,
  
• From the High E post
  
• From the midpoint between D and G?
  

Any ideas?

Anyone done this before?

Thanks

[JohnH]

I suppose the difference in post positions is to make a first pass correction for intonation, so you dont need to use up all of the adjustment range of the saddles just to get to roughly the right place.

Heres a suggestion: measure edge of nut to saddle on top and bottom strings of all of the guitars that you have which you are confident are correctly intonated, be they Strats LPs whatever. This measurement should be consistent for all guitars and depend only on the action height and string gage that you want to use. That should give you a reasonable clue, and put you within range of correct adjustment on the saddle.

I had a look at my guitars.

My Hondo has 25 - 9/16" at the high E string and 25-11/16" at the low E. My Shergold is pretty much straight 25-1/2", but may not be correct

[Runewalker]

After pondering this I realize there was a simple solution that depended on access to a Gibson or Gibby type. Just measure that one and find out where the 24.75" point is located. Duh.

Heres a suggestion: measure edge of nut to saddle on top and bottom strings of all of the guitars that you have which you are confident are correctly intonated, be they Strats LPs whatever. This measurement should be consistent for all guitars and depend only on the action height and string gage that you want to use.

This idea is logical. However, I seem to find small differences in string lengths between guitars for the same tone string, which surprised me. Funny that the low E is 26" or slightly longer in a 25.5" scale. I don't think I was expecting that. Of course the lengths on the same string tone will be different between the LP and strat scales. I don't have enough LP types to check between guitars. Of course I always say I don't have enough of all types of guitars.

But I am working on that!

[wolf]

Runewalker
I've got a Gibson SG Standard. Want the dimensions on that?

[JohnH]

I would think that since the neck has been designed with frets spaced out for a 25.5" scale, then the info you need would be based on measuring other correctly setup guitars with 25.5" scales. This may mean that Strats are a better reference than other SG's - I understand most SG;s have a 24.75"scale? - (I dont know for sure).. I would think the scale length is critical , more so that the design of the bridge, since the string doesnt know what piece of metal it is being bent over.

regards

John

[Runewalker]

Wolf: John's right, the SG is 24.75" and I am converting to a 25.5: scale. However, I do appreciate the offer, and what might be helpful is to measure from the nut face (edge closest to the first fret to whatever point on the tune-o is at exactly 24.75" On my LesPaul that point is the leading edge of the low E saddle.

I think I was over thinking this. When I have done this with strats I generally pick the midpoint of saddle travel.

John's idea of measuring string lengths among guitars, did give me a sample that I could interpolate.

I need to make sure that the longest string is covered by the range of saddle travel, which is smaller in a tuneomatic than a Strat bridge.

Thank W and JH.

[RJB]

According to all the setup guides I've read, the "scale" length is nut to saddle on the high E string. the other saddles are adjusted longer to compensate for the increasing string diameter.

My 2¢, is to set the high E saddle to roughly 1/3 travel and install the neck at the scale length there. That should give adaquate adjustability for all the strings. I would also measure nut to 12th fret as 1/2 scale length to verify what that length actualy is for that particular neck.

[Runewalker]

According to all the setup guides I've read, the "scale" length is nut to saddle on the high E string. the other saddles are adjusted longer to compensate for the increasing string diameter.

RJB: I have not run accross any sites on setups dealling with this ?, and don't have a setup book. But after reading you post I measured a couple of 25.5" guitars and the high e was right at 25.5. Measured a les Paul and it was 24.635" at the high E. So this is trending (albeit with a small sample size) your direction.

Thanks

[RJB]

Here's a setup page to get you started.
www.fender.com/support/setup/stratsetup.php
This basically follows the guidelines from Dan Erlewine's book.

Just remember, the scale length is determined by the placement of the frets on the neck, not where the bridge is located. If you just drop a neck on a body, and don't have the bridge placement matching the neck scale it will not be in tune past the first couple of frets.

Also when you do the intonation, don't rely on the 12 fret note compared to the 12th fret harmonic. I had a Squier that passed that test fine, but when checked with the "scale" length was off almost 3/16"!!!! Amazing the difference THAT made. A chromatic tuner is much better. Compare the open string in tune to the 12th fretted note. Then adjust intonation accordingly.

Happy building!!

[eljib]

Check out www.guitarplansunlimited.com and click on the LP/Strat Morph plans. It's a LP body fitted with a 25.5 neck. The plans cost $15, but maybe it's worth it to get the dimensions right.

Hope that helps.

[GuyaGuy]

RW,

scale length is most precisely determined by measuring the distance between the middle of the nut to the middle of the 12th fret and doubling this. this will give you the exact overallscale length, regardless of where the saddles are positioned. (after all they're shifted to accomodate tuning, esp the bass strings which are moved toward the nut because of their chunkiness.)



was that what yr asking about, RW?


also, read dan erlewine's guitar player book for info on scale, accomodating string types, etc.

[Runewalker]

GG:

"scale length is most precisely determined by measuring the distance between the middle of the nut to the middle of the 12th fret and doubling this..."

Why the middle of the nut and not the faceing edge (nearest the first fret? Middle of the nut would introduce variance between guitars, since nut sizes vary: Vintage strats at about 5/32", LesPauls at about 1/4" and Floyds at 3/8".

I can buy the measure to the 12 fret and double.

was that what yr asking about, RW?

The thread responses have been great. I am experimenting with different scale converstions: conventional Gibson type 24.75" converting to 25.5" and conventional strat types converting to 24.75".

Why?

This got started when I grafted an Ibanez neck onto an ESP body, the respective type had different heel and overhang characterics.

Now I am going a little wacky an putting a Jackson sharky on an SG style body. It looks pretty wicked, but I have have been told I don't have enough hair for a neck like that. Of course that is just the neck/body, the electronics are also tending to the alternative. But of course. this is GNutz.

RW