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Hi there, please excuse me if I don't use the proper terminology while explaining my issue, I'm a bit new at building guitars.

I put together a bass and a neck from two different basses. It appears from my estimation, that the base of the new neck is 1/8th of an inch further away from the bridge than the original neck.

Here are the intonation issues I'm having. I can intonate the open E and the E at the 12th fret, but many of the frets in between are sharp.

Can I take off 1/8 of an inch off the base of the neck and remedy this issue? Since it's just an 1/8th of an inch, do you recommend I file it down as oppose to try and cut it with a hand saw? I wish I had access to a belt-sander, but I don't.

your experience and wisdom are appreciated
thanks

Seems to me you first need to determine the scale length of the neck by measuring from the 12th fret to the front edge of nut. After you get this measurement you double it and this will be your scale length. This measurement will be the distance you should have from your nut to the bridge.
From there you can either modify the neck pocket or the front of the neck if you need to shorten the length, or you can move the bridge forward.
If you need to make the distance longer you'll need to relocate bridge farther back.
The scale length is determined by the fretboard so to properly intonate, the distance from nut to bridge must be accurate.
IMO I'd move the bridge to the correct position but it depends on how far off the measurement is. If it's very small I might file on the end of neck.
Good Luck

The only other thing to add to Van's comments is that the saddles do not go exactly at the scale length but rather some additional distance which compensates for string stretch. Exactly what that additional distance is depends on the type of bridge, which is why I pointed you to the StewMac fret calculator in your other post. Experienced bass builders can also tell you how much compensation they use or you can measure another instrument with the type of bridge you are using.

I would suggest that you need a bit more through evaluation before strategizing any serious modifications. Some measurements would be nice - face of nut to center of 12th fret, and nut to saddle measurements on the G and E strings would be a good start. More details on the components we're dealing with could provide for more insight as well (are we talking about a Warmoth neck on a Fender body, an Ibanez neck on a Cort body?).

Then a more thorough appraisal of intonation trends in different areas. Open string in tune, in what direction and to what degree do notes read sharp or flat in the 1-4 range, 5-9, 10-15, and 16-up? With these areas at least roughly measured and described, this can provide a lot more useful data for others to help appraise your issues and prescribe an approach for solution without seeing the instrument.

Just don't start cutting anything until you're sure the problems are properly evaluated and a predictable strategy for solution in place.

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Thanks for the advice.

What I ended up doing was matching up the old neck and body with the new body I bought. I found that the distance between the end of the neck and the bridge on the new body was longer by about 1/8 of an inch. Since the truss access is at the headstock, I was able to trim 1/8 an inch off the bottom of the neck where it goes into the pocket. I then did the old toothpick and glue in the screwholes and redrilled and attached the neck.

It's got proper intonation now.

Thanks everyone!

You do realize the end of the neck has nothing to do with scale length?

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