Jump to content

Notched straight edge shows subtle "bump" near 14th fret on fretboard??

Recommended Posts

Hi guys!

I'm new to this forum, and my reason for joining is simple. I've run into quite the (frustrating) conundrum while setting up for a fret level...I made my own notched straightedge, and attempted to use it to straighten the fretboard using the double action truss rod (trying on both my acoustic and electric, both of which need levelling). But no matter how much I adjusted it, the notched straight edge NEVER lied flat on the wood across the fretboard (ie always rocks up and down).

I even sanded the notched straightedges surface against a known precision straight edge, and still had the same problem. My theory is that the fretboards have slight bumps past the 14th fret (where the neck meets the body).

If this is the case, I think I would need to use radius blocks to reshape the fretboard. Has this happened to anyone? Can you provide any insight to this wannabe luthier? 

Many many thanks in advance!!


Link to comment
Share on other sites

Hi and welcome to the forum!

Since you have verified the straightness or your self made notched straightedge, it should be good for the task.

Especially on acoustics a hump where the neck meets the body is a very common issue. That may be due to the design, there's not too much wood under the fretboard over the body but the heel is a massive block. On electrics it's not that common yet plausible since the truss rod may not affect the entire length of the fretboard.

If you're refretting the guitars, a radius block can be used to straighten the fretboard. However, if you're just leveling and recrowning the frets, there's not much you can do. You can try to scrape the highest spot of the hump a tad lower, a one-sided razor blade is a good tool for that. The effect may be more cosmetic, though.

As we're talking about fret leveling, you can also use a standard straight edge to straighten the neck to the fret top level, leaving the bumps untouched. That way the frets would be lower at the hump area but if after leveling there's still enough metal left to call it a fret the result should be satisfying. A notched straightedge is a good tool for telling how bad the potential neck issues are and help to adjust the neck as close to straight as possible. If the hump is lower than a fret, i.e. less than 1 mm, filing the frets low at the problem area is a valid fix until it's time to refret the entire fingerboard.

Link to comment
Share on other sites

When I'm levelling frets, I don't use a notched straight edge - I only use a notched straight edge when I'm building the guitar and working with frets that have never been levelled. The reason for is that you want the frets to be level with each other and the fretboard itself doesn't matter.

So if you're doing a bog-standard fret level on a guitar, just use your regularly trust-worthy straight edge and adjust your trussrod the the frets are as close to level (with each other) as you can get them, then do your level and you should find that you remove much less material from the frets than if you get the fretboard itself perfectly flat with a notched edge because frets are often not hammered or pushed in evenly and fretboards were not always flattened properly before frets were installed.

  • Like 2
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...