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Old 06-19-2016, 09:50 AM
Hot Vibrato Hot Vibrato is offline
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Default Compression Fretting vs Planing the Board

I was on this thread: http://www.acousticguitarforum.com/f...d.php?t=433522 and someone mentioned that the only way to correct a bowed non-adjustable Martin neck is by compression fretting. I chimed in and said that compression fretting is a crude and imprecise way of doing it, and that far better results can be attained by planing the fingerboard. Then the vintage purists piled on, claiming that the guitar would be ruined or devalued by planing the board, and that no responsible luthier would ever dream of planing the fingerboard on a vintage Martin.

I've been doing repair work and fret jobs professionally for 21 years, and I always do them the way I was trained - plane the fingerboard until it's perfect, and then install the frets. The results have been wonderful, and my clients are always thrilled with the appearance and playability. Every Martin refret I've done plays at least as good as a brand new Martin. It never occurred to me or my clients that I was being irresponsible.

I've been familiar with the concept of compression fretting as long as I've been in the business, but it never occurred to me that it's a good idea. Why would you fix a wonky fingerboard by trying to force it into submission by wedging oversized fret tangs into the slots, when you can simply plane it out and know for a fact that it's perfect? I understand the idea of maintaining originality, but keeping a badly planed or warped fingerboard original, simply for the sake of originality, is insane. Is planing a few thousandths of an inch off the board here and there really such sacrilege?

I haven't seen much written material on the subject of compression fretting. The guys on the other thread were shocked that I don't know much about it, and that I wasn't aware that all the important luthiers do it that way (is this even true?). Is there an American Lutherie article that I've overlooked? A chapter in a book somewhere? For those of you who do compression fretting, in what cases do you feel that it's inappropriate to plane a board, and when is it okay?

Last edited by Hot Vibrato; 06-19-2016 at 10:02 AM.
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Old 06-19-2016, 10:06 AM
charles Tauber charles Tauber is offline
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Are your customers happy with the work you've done for them? Have you ever had someone complain about the work you've done to level/refret their fingerboard?

If not, carry on: it then isn't an issue, except in on-line discussion forums.

If so, you might want to consider their complaints and change methodologies accordingly. Same as any other service provided.



How many luthiers does it take to adjust neck relief?

10: one to adjust it and 9 to say, "Oh, I do it differently".
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Old 06-19-2016, 10:10 AM
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I feel I have to post up this video here, without comment.

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Old 06-19-2016, 10:12 AM
Hot Vibrato Hot Vibrato is offline
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Quote:
Originally Posted by charles Tauber View Post
Are your customers happy with the work you've done for them?
They love my work. I get emails, texts, phone calls just gushing about how much they love their guitar now.
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Originally Posted by charles Tauber View Post
Have you ever had someone complain about the work you've done to level/refret their fingerboard?
Never. Not once in 21 years and hundreds of fret jobs.

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Originally Posted by charles Tauber View Post
How many luthiers does it take to adjust neck relief?

10: one to adjust it and 9 to say, "Oh, I do it differently".
Good one! It's funny because it's true...
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Old 06-19-2016, 10:23 AM
Tico Tico is offline
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If they care the fingerboard wood is not planned so it stays at its original thickness no matter how un-straight the old guitar's unadjustable neck is, shouldn't they similarly care that the fret work replicates what was original?
I don't think this compression fretting process is 'authentic'.

I don't know, just asking.
Seems inconsistent to me.

Here's how it looks from where I'm sitting ... pick your poison:
1. Non-original fretboard thickness
2. Non-origional fretting
Or
3. A fully-original guitar that's hard to play.

I'm not arguing for or against anything, and don't have a dog in this fight.
I just have trouble understanding what I see as this apparent inconsistency when it comes to what is or isn't acceptable to keep a guitar suitably 'vintage' or 'original' yet playable, and not locking it up (unmolested but unplayable) up in a museum case.

Last edited by Tico; 06-19-2016 at 10:31 AM.
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Old 06-19-2016, 10:29 AM
Hot Vibrato Hot Vibrato is offline
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Originally Posted by Tico View Post
If they care the fingerboard wood stays at its original thickness no matter how un-flat the unadjustable neck is, shouldn't they similarly care that the fret work replicates what was original.
Compression fretting is not 'authentic'.
I'm not so sure. Martin invented the concept of compression fretting. I suspect that back in the day, they would plane the boards flat, and then install frets with oversized tangs to backbow the neck somewhat, and it would then (theoretically) go int a slight forward bow when put under string tension.

Sometimes you have to do a fair amount of planing to correct neck bow, but usually, it's just a few thousandths of an inch. Therefore the additional height of the new fretwire often makes up the difference in lost fingerboard material.
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Old 06-19-2016, 10:44 AM
Hot Vibrato Hot Vibrato is offline
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Quote:
Originally Posted by Tico View Post
I just have trouble understanding what I see as this apparent inconsistency when it comes to what is or isn't acceptable to keep a guitar suitably 'vintage' or 'original' yet playable, and not locking it up (unmolested but unplayable) up in a museum case.
You and me both. Many of my clients could be considered 'vintage snobs" (although I'd never call them that), and nobody has ever protested against me planing their fingerboards when it's time to refret. It seem that everyone has an opinion on what's acceptable when it comes to maintaining originality. Thankfully, my customers aren't as neurotic about it as some people are.
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Old 06-19-2016, 10:51 AM
Tico Tico is offline
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So far, to me, it sounds like one of those things where even the experts disagree.
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Old 06-19-2016, 11:08 AM
John Arnold John Arnold is offline
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I have had guitars where the fingerboard had been planed so much that the neck was uncomfortably thin near the nut. Typically, those were Martins where the neck was thin at the nut from the factory.
I have planed plenty of fingerboards in my earlier years, but the concern I outlined is real, and will tend to affect playability and vintage value. Also consider that reducing fingerboard thickness will make the neck less stiff, and may contribute to more neck bowing in the future. It is a similar argument that is often raised when shaving a bridge to lower the action. A thinner bridge can allow the top to belly more.
A third alternative (which I have mainly used on wartime ebony bar Martins and the later square tube reinforced Martins) is to remove and reglue the fingerboard with hot hide glue. A caul with a slight curvature is used so that the neck has a small amount of back-bow before restringing. If done carefully, it may not even require new frets.....provided the existing frets have sufficient height. A simple fret leveling may complete the job.
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Old 06-19-2016, 11:16 AM
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I want to be clear on a few points from the other thread...

I never said some planing a fretboard was always inappropriate. I did say I wouldn't expect it to be the first or only approach. Compression fretting may be used in conjunction with planing, assuming planing is appropriate for the situation.

When dealing with vintage necks there are variables such as rosewood fretboards, ebony fretboards, boards that have been refretted multiple times, steel T-bar necks, ebony reinforced necks, square tube necks. All these things affect stiffness. Planing all necks flat and not taking these other issues into account could result in unfavorable changes in relief with the neck under tension.

As John points out, removing the fretboard, inducing some back bow, and regluing with HHG is another solution that doesn't remove wood and is generally accepted by vintage Martin buyers. Richard Starkey was the first to explain it to me, although he probably wasn't the first to use it.
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Old 06-19-2016, 11:30 AM
Hot Vibrato Hot Vibrato is offline
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Quote:
Originally Posted by John Arnold View Post
I have had guitars where the fingerboard had been planed so much that the neck was uncomfortably thin near the nut. Typically, those were Martins where the neck was thin at the nut from the factory.
I have planed plenty of fingerboards in my earlier years, but the concern I outlined is real, and will tend to affect playability and vintage value. Also consider that reducing fingerboard thickness will make the neck less stiff, and may contribute to more neck bowing in the future. It is a similar argument that is often raised when shaving a bridge to lower the action. A thinner bridge can allow the top to belly more.
A third alternative (which I have mainly used on wartime ebony bar Martins and the later square tube reinforced Martins) is to remove and reglue the fingerboard with hot hide glue. A caul with a slight curvature is used so that the neck has a small amount of back-bow before restringing. If done carefully, it may not even require new frets.....provided the existing frets have sufficient height. A simple fret leveling may complete the job.
It's funny that you responded to this thread so soon. Your name came up in the other thread I mentioned, because someone said that you advocated compression fretting. I replied that I had seen your work and you did indeed plane the board at least in that one case. It was a D-18 that was shipped to you from a guy in Tulsa, probably in the late 90's. You replaced a chunk of missing top, and you also did a refret (and maybe a neck reset - I can't remember).

Your method of removing the fingerboard and regluing with an induced back bow makes sense. Of course, there would be a fair amount of finish touchup on the neck afterwards. Do the vintage purists complain about that?

To be honest, I've never removed a fingerboard on a vintage guitar that was of any value. It sounds a bit scary. Hide glue can sure be stubborn, even with plenty of heat. Do you ever have problems with the mahogany or rosewood splintering and causing cosmetic damage? Any tips to avoid this?

How many extra hours of work do you figure for removing the fingerboard, regluing it, and overspraying (or otherwise touching up) the neck?

BTW - How much curvature are we talking about with your fingerboard caul? Could you post a pic of it?
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Old 06-19-2016, 11:40 AM
Hot Vibrato Hot Vibrato is offline
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Quote:
Originally Posted by Todd Yates View Post
When dealing with vintage necks there are variables such as rosewood fretboards, ebony fretboards, boards that have been refretted multiple times, steel T-bar necks, ebony reinforced necks, square tube necks. All these things affect stiffness. Planing all necks flat and not taking these other issues into account could result in unfavorable changes in relief with the neck under tension..
You can't just plane it flat and expect it to be right under string tension. The way I was trained is to induce "simulated string tension" on the neck, and re-check the results several times during the procedure with the guitar actually strung up. This method is discussed extensively in both of Don Teeter's The Acoustic Guitar books, and in Dan Erlewine's The Guitar Player Repair Guide. FWIW compression fretting only gets a passing mention in those books.
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Old 06-19-2016, 11:50 AM
Tom West Tom West is offline
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Just to throw another log on the fire. When I first started building in the 70's I used a book written by David Russell Young,in it he advocated a solid steel non-adjustable truss rod that was 1/4" by 1/2". When making these necks one had to make sure there was back bow built in so that the board would end up with a reasonable relief when strings were tuned to pitch. If one use a perfectly flat board you ended up with excessive relief. This just supports what John A. is saying about using a caul to build in back bow to re-glue an existing fretted fretboard. While these neck were solid and usually were quite stable it was a pain in the butt and the jump to adjustable rods was a relief for myself.
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Old 06-19-2016, 12:28 PM
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Quote:
Originally Posted by murrmac123 View Post
I feel I have to post up this video here, without comment.

I'm a bit confused here because the first thing he does is level the fretboard and then does the compression fretting. So it's still leveling the fretboard which would be removing fretboard material and essentially thinning the neck.
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Old 06-19-2016, 01:13 PM
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I would like to mention a couple of things here which might be of relevance.

Firstly, AFAIK , the original frets on vintage Martins were .037" high. I could be wrong here, but what I do know is that .037" was the fret height on every Martin I ever owned up until approximately two years ago, when out of the blue, and with no prior announcement, I discovered to my surprise that the fret height on my new Martins had suddenly became .043". ( I have a theory as to why this change came about btw, but modesty prevents me from disclosing it}.

The happy consequence of this increase in fret height is that it is now makes it at least possible, ( if perhaps not ideal), to sand the correct relief into the fret tops themselves (always assuming you have the correct jig to implement this, and know how to use it to get the desired result). For .005" relief, which is pretty well what most players want, it would mean that the 7th fret would still be the old height of .037", and the first and fourteenth the new (improved ) height of .043"... give or take a thou.

Obviously, sanding relief into frets which start out at .037" high would not be feasible.

It may well be, of course, that the vintage diehards actually want to retain the old fret height of .037", and would spurn the idea of refretting with .043" wire, in which case my suggestion will be of no use whatsoever. I am simply offering this as a possible alternative to compression fretting or fretboard planing.

Last edited by murrmac123; 06-19-2016 at 01:22 PM.
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