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This is a followup to my other post on fretting under tension. I'm in the process of trying to compare some of my building methods to what others are doing. So my next question is on fretboard fall away, where additional taper is added to the tongue of the fretboard over the body. For those of you who do this, how much taper and what information are you using to determine that. Also interested in hearing from those who don't use any taper.

For the record I always radius and level my fretboards after the guitar is on the body, so to eliminate any slight hump in the fretboard that might develop when the neck is glued on the body. I have always worked with a fretboard that is dead flat from end to end with no taper.

Thanks in advance for the replies.

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Josh House

Canadian Luthier Supply
http://www.canadianluthiersupply.com
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House Guitars - Custom Built Acoustic Instruments.
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I use a 28' radius top (all braces) glued to a flat rim. The fall away of around .040 happens automatically with the correct neck angle that yields a 1/2" string height in conjunction with a 3/8" bridge, action set .090 bass, .070 treble...

Fall-away is desirable to me and as such on new guitars that I built or have built my process results in approx. .015" of fall-away from the 12th to the last fret. The idea is to free up the string plane from any offending and interfering frets especially for the countless folks out here who desire low action.

In the repair world when doing a fret dress milling in fall-away is often the first activity of the fret dress as well. On Fender-style bolt-on necks they are well known in the biz for developing a bit of a ski ramp with the frets over the body. For players who want low action.... this ski ramp needs to be milled away or it will be the limiting factor dictating a hard stop on action lowering.

Back to new builds: Fall-away can either be milled into the neck during the leveling process prior to fretting or built into your geometry by your methodology for how you build the upper bout and I wrote a bit about this on my site in a toot called "flattening the upper bout."

For me fall-away is desirable and something that is a plus in the final set-up.

I also like .015" fall away. Check out Frank's thoughts and method;
http://www.frets.com/FretsPages/Luthier ... fret3.html

Chuck

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Josh, I put some masking tape under the end of the fretboard, so it creates a slight ramp when the neck is attached. Then I level the fretboard. Then I fret, and level the frets, all with the tape in place. Once complete, take off the tape, and then you have your fall away when you glue down the fretboard overlay. Two layers of tape seems to be about right. it is placed right under the 20th fret, or thereabouts. This is with a 25' radius, where I have already flattened the upper bout. Just use enough tape to get a barely perceptable ramp, and you'll be good to go.

Jason

Not meaning to hijack the thread, but does a guitar with a raised neck and floating fingerboard need fallaway seeing as the whole fretboard acts as a single entity?

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"I am always doing that which I cannot do, in order that I may learn how to do it."
Pablo Picasso

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My take is that the desired fall away will depend a lot on the neck attachment system. A glued dovetail and extension seems to move less than some designs of a double tenon bolt-on. The goal for me is to get slight fall away under tension to allow for further settling down the line. This assumes you are not using a fully supported extension like Trevor has in his book.

With my Bourgeios-type double tenon system I seem to need a little more fall away which I actually build into the upper bout. Probably 1/32" unstrung which hopefully winds up in that .015 range under tension. I always level with the neck bolted on and will then fret to maybe 10 and support the headstock and add weight to the upper bout to simulate string tension and see what the junction and extension is doing. I can still fine tune things with sanding that area and extension if necessary and then fret.

The people at the store where I sell and who helped me with the evolution of my instruments saw a little fall away as really important on a new instrument and any rise in the extension was a deal killer.

The tape trick Jason mentioned is a great idea.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

I vote no.

I programmed in a .01" fall away into the fretboards of my electrics but discovered the neck simply doesn't bend at the joint where I expected it would. Since then I cut the fretboards according to a theoretically perfect compound radius design and the result has been a consistently more playable instrument.

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

I don't do it.

We fret the FB before its attach like Martin and many others, this I admit causes a slight downward bow of the FB extension -- for us this is a positive design feature since presses the extension tight to the sound board.

As a side bar I have a lot of Martin factory finger-boards here in the shop -- they are all made on CNC machines and they are all .015" thicker on the extension end than the nut end -- go figure?

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Ken Cierp

http://www.kennethmichaelguitars.com/

It's a "feature" not a defect....

Regarding fall-away for archtops it depends... What it depends on is the sort of archtop AND the individual player as well.

For example an acoustic archtop may have to compete with a band and since it is not amplified players may have to be a it heavy handed. By the way this is what led to the idea of amplifing a gutiar in the first place.

Many jazz players, not all, prefer higher action which if high enough can make the idea of fret board fall-away a bit moot. OTOH these days archtops may be found producing many types of music with all manner of players requiring what they require that can include uber low action in which case fret board fall-away may be very necessary.

In the last several years I am finding myself addressing ideas and notions with much more of an eye on who the payer is, what do they play, and how they play it - the individual style. As such set-ups can be as varied as we human bags of mostly water....

I try to not have any fall away. I don't really see the point in it especially for a cutout. Seems to me that as you go down the neck the action gets higher and higher anyway so why the fall away? Having said that it tends to happen anyway but I've been trying to eliminate it. I've been building true flat tops lately and trying to get rid of fall away by 'bending' the top right from the UTB to the neck block. I may try an arched UTB as well. In many of my old books they say that it's desirable or at least acceptable but I never really understood why? Is it something to help with future distortions of the string plane due to string tension?

Seems to me that as you go down the neck the action gets higher and higher anyway so why the fall away?

That observation (and for the most part I agree but fretting and angle have to be taken into account) is why I suspect


As a side bar I have a lot of Martin factory finger-boards here in the shop -- they are all made on CNC machines and they are all .015" thicker on the extension end than the nut end -- go figure?

I have a call in to an engineering contact at the Martin factory -- I'll let you know what he says.

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Ken Cierp

http://www.kennethmichaelguitars.com/

The reason for a little fall away, is so that over the years, as the string tension works away at folding the guitar in half, the fall away slowly disappears, and hopefully stabilizaes back to level. If you look at a guitar where the ramp has developed from the neck/body joint, you are just trying to build in the inverse of that ramp, so after settling, it's level. The guitar may never move, but it's cheap insurance to build in some fallaway up front in anticipation of that movement. Some of the repair guys would probably be able to comment on how often they see the 14th fret ramp/hump start to appear, and after how many years.

I am pretty sure on average, as the guitar ages and the dome increases and the sound hole area begins to get a little concave -- the angle of the neck seemingly moves toward the sound-board and the strings get higher off all along the FB. Wouldn't the fall-off fall farther or at least the same?

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Ken Cierp

http://www.kennethmichaelguitars.com/

What you are describing is correct, but also think of the 14th fret joint as a bit of a hinge point. The rim in the upper bout gives a little, allowing the entire neck attachmemt to move. Since the fretboard extension is glued down, it has no choice but to hinge at the 14th fret, giving rise to the ramp. My thinking on this has been that when that eventually happens, the fallaway will allow it to level out, and then I also make sure I dont short change myself on saddle height, so that the bottom of the saddle can be sanded, bringing the overall string height back down as well, to address that issue. Failing that, you are into neck reset territory.

Thanks for the response -- honestly my questions were rhetorical, in the 40 or so years I've been doing this I have never seen a situation where having the finger board taper down a few .000" where it would have made any difference what's so ever in a neck set requirement. That does not mean it couldn't happen. Once the nut end of neck gets above the sound board plane bad things are happening and you may be right the it may appear that there is hinging at the 14th fret but I am not getting the geometry where a slight slope will matter in the big picture.

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Ken Cierp

http://www.kennethmichaelguitars.com/

Neither do I. I can't grasp this hinge concept when the heel, heelblock and body are essentially locked together in that region. On a non cutaway- who cares - fall off , no fall off - no biggie. On a cutaway, I aim for straight all the way.


Sent from my iPhone using Tapatalk

I do have another thought (imagine that!) regarding this term "fall away." I suspect that its really not a process meant as a prophylactic measure but rather a tweaking operation to get an initial neck joint and set right on the money. Simply an adjustment to one of the several variables that can be used to get that finger board straight edge test to hover just over the bridge (I read where builder really obsess over this measurement). And I don't think its a bad thing -- if memory serves, David Russell Young illustrated such a process in his book years ago. And many classical makers do it as a matter of course.

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Ken Cierp

http://www.kennethmichaelguitars.com/

For us fall-away has nothing to do with prophylactic measures (if you had any idea how much restraint I am exercising here knowing how to photoshop all manner of stuff and people into a full body condom you would thank me for NOT doing so.... )(perhaps not too.... . Nor are we addressing and attempting counter future upper bout distortion, body joint humps, etc.

Instead I'm am going to give you guys a hint here hoping that this can be of value to many on the OLF.

It's not about belaying the eventual need for a neck reset, body joint humps, or a partridge in a pear tree. Good guesses though!

What is "related" to why some folks mill in fall-away is Mr. and Mrs. player, desired action, and eliminating limitations of a specific instrument. It also may, I say may have something to do with a player's technique and attack.

Any takers? The first one to correct guess is the weiner and wins a tub of OLF lard....

Start by explaining who's --- for us? I look forward to reading your views and opinions regarding this terminology

Also:

adjective: prophylactic

1. synonyms: preventive, preventative, precautionary, protective, inhibitory "prophylactic measures"

noun: prophylactic; plural noun: prophylactics
1. synonyms: preventive measure, precaution, safeguard, safety measure;

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Ken Cierp

http://www.kennethmichaelguitars.com/

Thinking about the hinge idea I would think that would make it worse over time unless the tongue was free to slip with the distortion. If it's fixed (glued) then I would thing that distortion would actually cause a hump. I would also think that too much fall away could be a problem with back buzz though the amounts that you guys who do it report are indeed very small.

So let me think out loud here... I'm guessing that for those who impart fall away they aim to have slight relief from the nut to the body joint (or a determined fret mark) and then a slight drop to the end of the fret board. As a player approaches the fall away... I don't know I can't think of anything...

So here is my exchange with the Martin factory Engineer regarding why their finger boards are actually thicker on the extension than on the nut end (counter to the fall away concepts). The explaination makes perfect sense!!

Hi Mark,
Wondering if you have some technical insight regarding an observation I made regarding Martin Factory specs for fingerboard thickness. There seems to be a trend with some boutique makers to taper the extension end of the fingerboard (calling it fall off or fall away) making it slightly thinner -- there are all kinds of, frankly non convincing explanations as why this is a good thing.

So here's my question -- if my measurements are correct Martin does just the opposite the loose boards I get from the factory and the ones glued in place are actually thicker on the extension end than the nut end -- I'd like to know the reasoning behind that design strategy.

Any information that you or others can provide would be appreciated.

Thanks in advance,
Ken

Hi Ken,

We put a taper of roughly .010 from the nut end to the very end of the fingerboard. The reasoning is that the radius on the fingerboard thins out the edge of it as the overall width changes from (narrow at the nut end) to (wide at the very end). By increasing the thickness throughout the length, it helps keep: side dots centered to the bottom edge of the fingerboard, the end fingerboard from cupping due to fretting, proper bridge height/fingerboard drop.

I hope this answers your question.

Thanks,

Mark

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Ken Cierp

http://www.kennethmichaelguitars.com/

Yep makes perfect sense. Another way to view it would probably be that they are maintaining the same height at the edge of the fingerboard all the way down it's length.

Interesting. I always put side dot's in after the radius for this very reason. But none the less the dead center of the board will be thicker at the bridge end. But that is probably ok since you are closer to the saddle at that point and any fretted notes there will have a larger angle.

There is nothing that I appreciate more in seeing is when we want to know something and someone goes to the source and actually asks! Good going Ken!

My read of the reply is a bit different though and I don't see it as counter to the fall-away concept. I most certainly could be wrong too, I am rather good at being wrong by the way...

Anyway what I am understanding from Martin's reply is hat they are addressing the question about the boards thickening and verifying same listing some reasons why.

But in the greater context of how Martin builds guitars they also flatten the upper bout removing any radius which also creates fall-away automatically. This is how I build my own stuff too and have a toot on my site called "Flattening The Upper Bout" that discusses why it's done to achieve fall-away with some added benefits such as not having to do any unnatural acts to get the fret board extension to lay nice and flat in that region.

By flattening the upper bout fall-away is engineered into Martin's designs although thickening the fret board can counter this to some degree too.

Martin does mention "fret board drop" which is also fall-away perhaps.

So my read of this communication is not that Martin does not do fall-away and again I most certainly could be wrong.

Regardless though why we (our shop) induce fall-away and many others do too has everything to do with how strings vibrate, players play, desired action, and removing one limiting factor that can prevent an instrument from being set-up with the desired action.

Fall-away also very much benefits electrics and in our repair world anyone who does much in the way of repairs will know about the Fender style, bolt-on necks and the "ski-ramp" that often happens (most of the time by the way...). This rising of the fret board over the body becomes one of the most profound limiting factors in these guitars to achieving buzz-free low action. So any fret dress of this style of instrument at least for our shop starts with milling away the ski-ramp. The same holds true for acoustics as well although we rarely see them ski-ramp what we do see is the absence of fall-way which in an of itself becomes a limiting factor to low action as well.

So fo us, meaning our shop and many pro Luthiers who I know personally who do this too fall-away gets you a couple of things. First it helps to eliminate the limitations from getting low action that not having fall-away can't do. Much of this is science having to do with the strings and how and where they vibrate and how the waves travel, react, etc. I'm going to ask Dave to come along and explain this part knowing as I do that he understands it better than I.

Additionally as we all know players have different styles, levels of attack, picks, no picks, Robin Hood arrested development, etc. So the players and how they play is part of this answer too in that an instrument with no fall-away may be perfectly fine for some players and absolutely unworkable for others.

I watched a client with a new Breedlove last evening use his thumb to pull the low e out about 3/4" and then let it slam into the frets..... This guy needs fall-away.....

I'll ask Dave to weigh-in here when he can and shed more light on how the strings vibrate and fall-away. We have a "mono-cord" set-up on a surface plate that he uses for these kinds of experiments.

By the way for builders we can't always know who will end up with an instrument that you or I built. Having fall-away will permit different set-up possibilities that not having fall-away will not permit. That's why I do it when I build my stuff as cheap insurance against that one player who thinks that they are Robin Hood....