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Hesh recently spoke about leveling frets with precision, which is an attainable goal for a professional shop.

But basement builders like me don't have a professionally-equipped shop and aren't about to invest in one for what we do, but we do want to do the best job we can with the tools at our disposal.

Hesh mentioned his shop's sanding beams to be true to within .0005" per, roughly, a foot. Yikes! That's half a thousandth! I don't happen to own such a beam, but I do have some aluminum sanding t-bars and a aluminum carpenter's level. I can make an attempt to flatten these a bit (scary sharp) on my granite surface plate. Any idea if that would get me, the amateur luthier, 'into the game'?

And any other insights we home builders might be able to use?

Thanks!

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Peter Havriluk

It’s not that hard. My leveling beam is a foot long 1”x1” square steel tube from Home Depot. I flattened one side on Stickit sandpaper stuck to a sheet of 1/4” plate glass. Stickit paper on that side of the beam finishes it off. It’s truer than I can measure.

Aluminum moves a lot with temperature changes. I don’t know if that would cause you problems or not.

I still use the plate glass for larger surfaces like the beam or a plane base, but for scary sharp, I did move to a surfaced granite block. Handling the glass plate so much was worrying my toes. That was the “scary” in scary sharp.

I've been using the same aluminum level for 45 years. It is plenty flat. A super precise bar loses its precision after you attach a strip of sandpaper to it and start grinding away. A good fret level job is more about technique.

Getting the SM leveling beam was game changer for me and my fret work but there's no reason why can't true one up on glass as mentioned. the .005 is probably even overkill really. But it is nice for sure. BTW the leveling beam has many other purposes too.

There is an interesting article in American Luthiery #113 by Mark French on how to make flat beams by abrasive rubbing of 3 flat-ish surfaces against each other systematically. A mathematically flat plane is the only possible shape common to three flat surfaces.

https://www.search.luth.org/making-a-tr ... nding-bar/

Find a local machinist and make your own leveling beams it's easy to do.

Purchase 1 X 2 aluminum tube stock (it's rectangular but called tubes by the industry). Cut one length that spans the 1st through the 12th and a second length spanning the 12th through the last.

Borrow or access a certified surface plate (machinists have them, we have them too). Put self stick 3M paper 120 grit on the plate and mark up both narrow sides of the beams with red marks-a-lot market.

Sand, floss, burnish the beam on the plate with the 120 paper on it being sure to move around the plate and not stay in one spot. When the red is gone repeat. Now remove the paper from the plate and go 220 and repeat. Now your beams are accurate to what the plate is accurate to over their spans. I'm home now so I can't measure my beams or I would.

You only need two beams and they can be made very inexpensively and these are more accurate than any commercial offering. Many of the commercial offerings have some flex in them and that's an absolute deal killer. We will be bearing down at times so no flex permitted.

I have 120 on one side of my beams and 220 on the other and that gets me where I want to go. I have longer beams for basses and shorter beams for mandos.

A short beam is also useful to nix ski ramps on Fender style bolt on necks.

Regarding Durero's post yes that's a machinist technique and I believe how surface plates are maintained too with three of them. We find that none of this is necessary and our beams are accurate enough to achieve any possible action settings that we have ever been asked to do in the tens of thousands of guitars that we have repaired.

As far as maintaining the beams accuracy we used to check ours on the surface plates every year and then after ten years of no movement we stopped. They seem to hold their true for a very long time.

Yep I use mine all of the time as mini surface plate to flatten nuts and saddle bottoms or put a bevel on a bridge pin so it does not catch the string ball.

As long as you are making your own beams, you can also true up L and T shape extrusions for use as under-string levellers.

We don't. We don't use them and don't see any need for them. We also never, never, never spot level it's the entire fret plane for us or nothing at all. Strings see the entire fret plane so that's how we have learned to see it too.

I know people do use them Josh but they are not in our religion....

The only time we address say a single fret is when it's loose then we reseat, clamp and glue and Dave also invented a tool made from a spring loaded Awl that has a grove to ride on the crown of a fret. It's pressed into the fret usually the end that is loose and at some point the spring releases with a bang and the fret is power seated. We then glue. If it won't stay down we clamp and glue.

You're right anything can be trued up on a surface plate and the hope is that it has zero flex so it stays that way.

I don’t do full fret levels with Understring beams. I do use a short understring beam, only occasionally and in particular circumstances.

A scenario where I might use it is where:

- The instrument already has a perfect or very good fret plane except for slight ski-ramp in the upper frets and levelling the whole board would mean unnecessary removal of height from frets 1 - 12 and
- The instrument is mostly well setup and not requiring much adjustment and
- Client is price-sensitive

In this scenario I can use the short understring beam before removing the old incoming strings to nix just enough of the ski ramp that the axe plays well at the desired target action. Then remove strings, quickly recrown frets 18-21, restring and setup and get customer out the door for the price of a setup within the amount of time a setup nominally takes. Using the understring beam to deal with the ski ramp means I can test as I go and remove the minimum necessary to play clean without spending any more time than necessary, so customer goes away happy and I’m able to still bill at my standard rates.

Check out what Music Nomad has to offer. There beams a bit more cost effective than Stewmac especially if you qualify for discount.

https://www.musicnomadcare.com

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Get a quality fret rocker first, in the 10 to 15 USD mark. Cheap ones are not straight. A bad rocker and a long beam are a recipe for disaster when you start.

Start with a 6 inch beam. Flatten it on a known flat surface like a 3/4 inch granite kichen top and use 300 grid. Begin on used guitars, not new builds and make the fretboard perfect. If the neck is good you can get an action of 1.2 mm and lower this way. Work slowly, with method, don't grind of much.

A fret rocker is not for leveling frets it's a quick check and should never be used for anything other than finding high frets. Leveling should always be done addressing the entire fret plane at once.

6" is too short and only used professionally for the 12th through the last and inducing fall away. At a minimum you need a beam that spans the 1st though the 12th and a short one for the 12th though the last.

Alwin your information is incorrect. Are you a professional who works in the trade? Please read what I wrote earlier in this thread.

So I offer again you can make your own beams, we do out of 1 X 2 aluminum tube stock cutting to length and safing the edges on the ends and sides. Some self stick 120 and 220 and a visit to a machine shop offering to buy lunch for a couple hours use of a calibrated surface plate (we have our own) and you can produce beams accurate over their spans in flatness to 0.0005" quite easily.

Use magic marker, we like red Marks-a-lot as "bluing" to check progress. When you remove all the red in one short session the beam is level.

Additionally I used to be tasked with doing this same set-up annually to check if the beams are changing over time and with use. After checking for about 6 years annually and seeing no movement we don't check anymore it was not productive they stay pretty flat.

Be sure to flip the beams and turn them around periodically to reduce errors from technique and/or the plate.

This produces a set of beams that may only cost $10 for two of them if you find a machine shop that appreciates you are guitar makers or repair folks.

Murray McCloud who we have not heard from for a while and I hope he's OK is an OLFer who offered these beams made how we do for sale at reasonable prices.

With this said our method of producing beams is way cheaper than the StewMac beam which is excellent by the way and has more heft which can be a good thing than ours.

Question for the pros - I have an old trash guitar with extremely un-level frets that I've decided will be my first patient. I have a piece of a small extruded aluminum I-beam that I flattened on my granite counters and no feeler gauges fit underneath - seems good enough for a first try.

I leveled the frets yesterday and holy crap, there is a lot of crowning work to do on some frets. I got all the wear out of the cowboy area at about the same time as I started to touch the scattered low frets (7, 8, 12).

Is there any special step when frets are so uneven? Or same as always, just crown it til it looks like a fret again? Seems obvious but I don't want to miss something.

Having uneven frets is not unusual. After frets are level use a Sharpie, or similar, to put a mark on the top of each fret. Crown the fret until only a thin mark is left in the middle of the fret. Finally polish the frets and do your setup.

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Steve Smith
"Music is what feelings sound like"

Before crowning, the first step is to get the frets level. A red sharpie also helps this process. Mark the top of the frets then use your sanding beam until all frets have been touched by the sander. It is helpful to have a long beam to keep things even. Mine is 18” long so there is never a high section of frets when I’m done.

If your frets are really uneven you may have to lower the high ones a bunch. If they are really bad, you might need to pull the frets and level the fretboard.

Yep, I've got them level - obviously my question could be more clear.

Because they started so unlevel, some frets have a wide flat top and some have been barely kissed. Others now have flat tops of irregular width from bass to treble, because their radius is clearly inconsistent - some were bashed down at the ends and some were not totally seated (but glued in place so do not move). I did get the neck as close to straight as possible before I started.

Given that I'm doing this over several days I figured I would ask if there's any special considerations for crowning, given how strange things look at the moment.

With a red sharpie, mark the tops flats and then crown until you have a fine red line showing. The top of the fret is the only thing that contacts the string so make the fine lines equal and you will be fine.

So there is more to doing quality fret work than the tools you use and/or just leveling things. Half the guitars out in the wild have bad necks with more relief on the treble side and less on the bass side.

There is also the issue of working smart with an example being how you described the cowboy chord area being the most divioted.

Experienced luthiers know how to manipulate the truss rod and neck shape so we can concentrate on the bad areas and don't have to spend our lives recrowning to a great extent areas that are still in relatively good shape.

The "bluing" or in this example red Marks-a-lot marker it not just something you work to remove. It's a road map to how to approach the work piece AND a time tested indicator of varying degrees of success.

So my posts above describe the use of 1 X 2 aluminum bar stock that is very stiff and over the ten years that we checked our beams every year on a calibrated surface plate the beams did not move at all. The notion that the level set leaves us when you put sand paper is not accurate unless you used poor quality paper and you have not tested the paper over it's span and randomly only adopting papers that are made consistently. We found Saite and 3M gold to be suitable. You also can cancel out many of the errors in the paper simply by turning your beams around when using them frequently....

So yes in the small builder build an acoustic guitar world marking the neck, using a level or similar thing that you have checked for flatness can get you by.

In my world it won't get you by with guitars that require greater accuracy such as one I did this morning an 18" Heritage jazz box with 14's.... yep that's 14's that the player a MSU professor wants uber low action. Folks levels here won't get you to where he wanted to go and that's why we only use very accurate tooling. Accurate need not cost much at all though you can make your own. We did.

Also one of the many comments I read above that is also incorrect in my experience is using a foot long beam. Your primary beam needs to span the 1st through the 12th and then you need a shorter beam to go from the 12th to the last. You never, never, never spot level that's not accurate and remember a string is a natural straight edge too.

The cost of making these beams is mouse nuts when you purchase your bar stock and do it yourself. That's what I did and when I was an apprentice approaching 20 years ago one of my first tasks was to make 4 sets of beams for our shop so I spent a couple of weeks on the surface plate.

So back to the bluing it's an indicator of the level set AND an indicator of the crown. It's also an indicator of relief too..... I had a hell of a time trying to get someone here a few years ago to understand what the "line" is that the bluing leaves and that we don't want to break. When we mark the fret the red will be as wide as the level part of the fret. If you hogged off a lot of the crown the red could be as wide as the fret wire.

With our crowning files we remove the flat top and replace it with the.... "crown" of the fret which is a gentle curve with a very narrow top in the center of the fret. The narrow top is the line. When properly crowned there will be a think red line unbroken over the length of the fret that remains and on both sides of the line the ink will be gone and the fret gently curves downward hence the term crown. We want to preserve the narrow, red line.

So when we just level all the frets and recrown and call it a day a lot of things that are not great may remain and even cause issues.

When the guitar is strung up and under string tension how the neck responds will be as individual as the wood that it was constructed out of. The relief level on the bass side may revert to less than the treble side and the treble level of relief may increase.

So the first thing we do before diving in is to observe the neck under full string tension, tuned to pitch and in the playing position. Then we make a mental note of its shape so we can change that shape if we want later.

So back to the red marker. Once we remove all the marker from all the frets which is not how I do it by the way and more on this in a minute. You may think you leveled the fret plane. You haven't because again under string tension it will change and even the strings you use will have variables that we can address.

If the neck I observed before starting to do the job has more relief on the treble side and less on the bass side which 50% of necks off the bench have I want to reverse this and reshape the fret plane for better playability. Once things appear to be level I remember my mental note of the fret plane and will now begin to do additional leveling while either pulling or pushing gently the head stock with my fingers while using the long beam. The neck is also resting on a fulcrum now half way between the 1st and the 12th.

For example once it's level or appears level but I want to remove relief from the treble side I pull the head stock gently toward me upward while leveling ONLY the treble side of the neck and counting strokes. I may go 6 strokes additional with 120 paper. This only hits the first several frets and the frets after 10 or so and reduces the height of these frets effectively raising the middle frets that had too much relief. Now relief has been reduced on one side only.

Likewise in this example I also want to also add relief to the bass side I push the headstock gently downward with my finger tips and only use the beam with 120 paper on the bass side hitting frets 4 through 9 or so and this mills in more relief on the bass side.

All the while before I begin the final shaping I also have used a short beam with tape on one end to raise that end on frets 12 though the last frets to mill in "fall-away." Higher action acoustic guitars may not benefit from fall-away but nearly all electric guitars AND guitars with bolt on necks greatly benefit from fall-away.

So it's not as simple as some posted above to do professional level fret work. We can shape the neck anyway we want including delaying the need in some cases, not all for a neck reset by reducing the height of the first frets and leaving the last frets full height.

And again I can add or remove relief at will anywhere I want. This, buy the way the shaping of the fret plane should really be a required activity for any builder who sells their wares. Some shops do these things and they are some of the highest quality instruments you can buy or that are produced these days. By doing these things I mean relief where you want it and fall-away.

Not breaking the red line with recrowning is difficult and comes with experience. Dealing with heavy recrowning is difficult and I get tired now a days so my business partner and friend Dave Collins recently invented the Fret F**** which is a motorized crowning tool that works fantastic and speeds up recrowning perhaps 5 times or more for us.

Others may make what they do and what they use work but it's impossible to compare results over the Internet and I know from experience that very high quality fret work is in very high demand by many players but the acoustic crowd is not where the need is the greatest and you can get by with using levels, counter tops, whatever.

Now take the action down and see how low you can get before every note on the neck remains clear as a bell with no slight sizzle or worse developing as you lower the action. Be sure to play every note with a moderate attack too. You may not like low action but millions of people do and it remains the single most common request that we receive daily.

FYI a high precision fret dress takes me about 2 hours doing all things mentioned above and that also includes a full set-up where I take the nut slots down and do other set-up things to the guitar.

Getting the scratches off the frets is something that hobbyists rarely do well and it is a bit difficult too and that's another conversation. As is fret ends and what shapes are decent and the many shapes that suck. Even the bevel angle is key to get right or that greaseball weekend wedding player that I use as an example here may come into your shop complaining that the string slips off his Les Paul fret ends because the prior shop that refretted his ax over beveled the ends. Fret ends can not be added to by the way if you remove too much material....

Most of all though fretting and quality fret work is an art and my friend John Hall has a saying that applies here - you do not know what you do not know until you know it.

Daniel if I can help you please PM me I am happy to help.

Thanks Hesh - I have no illusions about yielding pro-level work on my first try! I am honestly wondering if I should have started with easier patient, rather than the most farked up instrument in the house. Time to get out the file and be patient. If I can get a job that plays well and doesn't look like absolute trash, i'll be pretty stoked. Then I'll do it again a time or two.

My medium-term goal is to do a level/crown/polish on a mandolin I want to sell - It's one of those $4-500 ish things so not really worth enough to pay a pro for the job but I wouldn't feel right selling it on reverb/Mandolincafe in its current condition. Then fix my 25-year old carvin bass, etc etc....

Daniel you are doing great and I applaud you. It's great to see folks here venturing into repair work and even more importantly wanting to actually do a quality job or as good as they can with what they have.

The mando is the same and in some ways I find them easier. Usually less material is removed since there is less material to remove... Smaller frets I seem to be able to crown faster too. I don't do fall-away either on mandos so that saves a step as well. I use a beam that spans all frets at once. The smaller frets sand and polish faster too in my experience.

Ping me if you need any help Daniel and again good going for wanting to learn this stuff.

Wanted to add for Daniel an important set-up spec for a mando.

The nut slots are as per my toot on setting up an acoustic guitar, very low.

With slots done and relief set I set mandos at <3/64th" on the treble side and <4/64th" on the bass side. We are fretting 6 - 8 strings at once so they need to be very low like a 12 sting guitar. The slightest hint of rattle is usually OK for players who have to compete with a banjo when they dig in.

Got a followup for future newbies.

I ordered a couple different crowning files from Amazon, not wanting to spend big bucks (yet). One curved diamond file labeled "baroque" and one safe-edged triangle.

I was not able to get decent results with the diamond file. Even the smallest radius seemed too large. My experience is extremely limited though, so the problem likely lies with me. I sent this file back.

I used the triangle and got something usable. The safe edges work well but I almost wish they were a little smaller - it made it difficult to work with the small mandolin frets. Again my inexperience is speaking here, smaller safe edges may have yielded a messed up fingerboard. Both the guitar I started on and the mandolin I did next had a lot of material removed on some frets, so it took a long time to get them back to something resembling round.

The mandolin now plays better than ever before, and the frets look normal even though I can find some unevenness on the profiles if I look closely for it.

I may try one of the nicer files for future work - both the Stewmac Z file and the Music Nomad diamond (that has no diamonds in the center strip) look interesting, and though they are pricey at $80-90 that's still 1/3 the price of a good fret leveling job here.