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While cutting the slots on a new board my template came unstuck from the fingerboard. One slot is about .020" out of place. That is about one thickness of the kerf on the blade used to cut the frets slots. Is this enough to pull off the intonation of that fret. I think its around 10th or 11th fret. So that is one that gets used alot. But it is also still one of the larger frets spacings and would be a smaller percentage of the overall size of the fret.

Can I fill the slot with rosewood dust and CA. Is that a valid fix? Would it be visable next to the fretwire? Should I just scrap this fingerboard above?

Thanks for any comments...

Joe

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Joe

Hi Joe;

If this is a commission instrument, I would scrap the board and start over, if it's something you can live with as far as a fill and recut, I would still scrap the board. On a 10th fret or so, assuming 25" scale roughly, the intonation will be off as much as 20 cents sharp or flat on that fret if you left it at .020" off. percentages and accuracy is harder to calculate and is more critical as you narrow up the frets. Fingerboards are not that expensive, so I would just make a new one, but that's my opinion.

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Nehemiah Covey
www.coveysacoustics.com

I'm no expert, but here's my read.

If a fret is off by any amount, it will affect intonation. Whether it's enough to hear is another question. That depends a lot on the player and on the listener's ear. As for the player, a beginning to intermediate player will inadvertently bend a string a bit as he frets it due to less-than-perfect fretting technique, particularly as he moves further from the nut. The pitch shift from these unintended bends could easily have more of an impact than the 10th fret being off .02". Also, beginning to intermediate players will often deem a guitar to be in tune when a finer ear would say otherwise. Bottom line, the intonation problems created by the .02" could easily get lost among the numerous tuning/pitch issues that arise when a beginning to intermediate player plays the guitar.

On the other hand, I think an experienced player with good fretting technique and a decent ear would notice the .02" intonation issue immediatley.

If it were my guitar, I would fix it or replace it. It's not a big effort to fix, and even if the repair is unsuccessful, a new fretboard is not that big of a deal.

As for fixing it, I would start by cutting a slice of rosewood about the same width as the slot. I would probably make this just by using a handplane to take a moderately thick shaving from a piece of rosewood and then sanding it until it fits snugly in the slot. Then I would use white glue to glue the shaving in the slot, and clean it up after it dries. Then I would use CA and rosewood dust to address any gaps left over. If the repair is not super clean, the repair may be noticeable from the side of the fretboard. If so, I would probably use this opportunity to make a bound fretboard. Don't worry too much about whether the repair is noticeable from the top of the board; the fret should cover the repaired section. (But double-check to make sure that's true.)

If that doesn't work, a new fretboard is cheap and not that much work.

Please take pictures of the mistake and your repair.

You can judge a craftsman by how well he covers up his mistakes.

Ive done this a few times. I generally start again with a new blank. if it was ebony you could probably get away with filling the slot with ebony dust and superglue but in the case of rosewood I think the fill job would be harder to hide...depending on grain in the rosewood.

I'd probably fill the slot with a sliver the same size, cut the slot in the correct location and bind the edges. There would be no visible sign unless someone pulled the fret. I wouldn't want to trust dust and CA as it would be holding the fret tang on that side. A sliver of wood glued in would be better IMHO.

This is a personal guitar right Joe? If it were for sale, I'd just make a new board. EIR fretboards are pretty inexpensive. Now if it were Brazilian, that's a different story.

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So what actually happened? If the fingerboard came unstuck from the template, how could you cut another slot after that? And how accurately were you able to attach the fingerboard to the template after the mishap? In other words, are you absolutely sure the fret slots from 11 and up are not also out of position, relative to the first 10?

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Rian Gitar og Mandolin

Ha ha thanks guys. I was just cutting up some fingerboards in advance of my next few builds. This is not a commission of any sort. I prepped 4 fingerboards in the planer and decided to pull out the SM miter box and cut the slots too.

The first 3 worked flawlessly as did all the others I have done. When I got to the 4th one, I had used the same double face tape to stick the template to the first three. My template has a slight V at the mouth of each notch. This helps align the pin. Once pulled into pin and set agains the side of the jig, it is secured. When the double face tape failed, the template moved away from the pin just enough that the pin was in a small section of the V and not all the way in the groove. The slot was cut wrong. As wierd as it may seem, it looked off to me, so I stopped and check. It was off. Using the previous slot as a guide, I set the saw back into the kerf and moved the template back into place with new tape. I checked all the slots one by one and the template aligned fine. So I cut the remaining frets slots. The only one out of wack is the one mentioned. Its no biggie and I can just toss the board out, but I didn't want to toss it if it wasn't going to be noticeable. I think the boards cost me about $8 each in the rough.

I have a pretty good ear, so I think 20 cents off of A-440 would be very noticable to me. I don't want to risk a build not working over an $8 fingerboard. I may try to fill it in and see what it looks like, but I doubt I will use it for anything more than maybe some inlay practice etc.

Thanks,
Joe

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Joe

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Joe

Joe,

With your ear that will drive you crazier then the blown bridge pin spacing on my #4.


Steve