A lot of you have been waiting for this penultimate step of our guitar aging project, so let’s do some damage!
Welcome back to Mod Garage. Today we’ll continue to work on our aging project, and some of you might be wondering why there was such a long break. The reason is simple: suboptimal timing from my side. The last part of this column was in the middle of autumn, and I wanted you to do the following steps outside (if possible) and not on the kitchen table. Wintertime is not the best time for such a challenge but now is a good starting point, so let’s go!
We’re almost done with our project, can you believe it? In this installment, we’ll take care of the color, talk about fading, and we’ll crack the lacquer—something a lot of you have been waiting for—before we add some dings and dongs in the last part of this series, which is the final touch before we put it all together again.a
We also have an advice column on aging from my friend and colleague Matthias “Matti” Meyer, from the German-based Bassart Guitars. Matti is one of the best pro agers I know. Please follow his advice and recipe for aging wood at the end of this column—we will need these tools in the next and final part of this project.
Aging the Color
Over time, the colors on guitar bodies start to fade, and depending on the type of color and the paint-job method itself, discolorations can show up. The two main factors are if the guitar was exposed to ultraviolet light and if the paint job is all intact. A famous example is the Gibson Les Paul goldtop guitars with the golden color turning greenish, or the Gibson sunburst Les Pauls losing the red color of the sunburst spray job over time. But Fender guitars also suffer similar problems.
What we want to mimic is an old nitro lacquer, but with our Harley Benton guitar we have two problems:
- The mustard color is not a real TV yellow, as discussed before. TV yellow is much lighter, so even when we find a way to fade the color, it won’t look like a faded TV yellow, but a faded mustard yellow. We can’t change this easily, so we must work with what we have and love it for what it is rather than hating it for what it’s not.
- It’s not nitro lacquer on our Harley Benton but a modern, not-so-thin, ultra-durable poly lacquer. In a technical way, this modern lacquer does a much better job than any vintage nitro stuff regarding protection of the guitar. The downside is that we can’t make poly look like nitro when aging; it will only be an approximation. But again, it is what it is, and we’ll make the best out of it.
If you have the time, exposing the guitar to direct sunlight for some weeks or months will cause a fading of the color to a certain degree. Over the years, I’ve seen the oddest attempts to do such things, including regularly placing the guitar inside a home solarium. Using artificial UV light is also an option but building a well-working construction for such a big object, like a set-neck guitar, is not easy and you’d need a lot of UV lamps for that. Such devices are often used to make yellowed plastic materials look shiny white again. An overspray with the correct color is also an option. but a lighter color on a darker one is always difficult to do—especially with a semi-transparent color like TV yellow. And I doubt it’s worth the time and money. Not everything is doable and this falls into that category. But we’ll do other things to make it look old and cool, so leave the color as it is.
Let’s begin. As usual, grab your steel wool and abrasive cloth to break the shine of the high-gloss lacquer, and don’t forget the backside of the neck. The difference can be seen in Photo 1 (before) and Photo 2 (after).
Aging the Lacquer
This is what a lot of you have been waiting for and today we’ll finally do it: cracking the lacquer!We all know the look of cracked lacquer on vintage guitars, which is part of their special appearance and charm. On vintage guitars this happens over time, the softener disappears, and the paint starts to crack. Here again, facing that our Harley Benton is poly and not nitro-painted, we must follow a different route to get a good result.
Generally, there are two basic methods to do this:
- Mimicking the cracks by using a razor blade to cut the cracks into the paint.
- Using a combination of heat and cold to crack the lacquer.
In both cases this is only the first step. Next, we’ll have to make the cracks more visible, but first things first.
I decided to use the second method: using heat and cold to crack the lacquer. Please note, this will take some time and patience to do it right: It won’t be done in 15 minutes. You don’t need much for this, just a heat gun and several bottles of cooling spray. The process is easy but safety first: Only do this outside, wear gloves and goggles, and place a bucket with cold water or an extinguisher near you … a heat gun gets very hot!
You can’t do this in one step, and you’ll need to work in smaller areas, one by one. Heat up the first area with the heat gun and be careful—you only want to heat up the lacquer and not melt or burn it. If you want to intentionally add some burned spots, a heat gun is the way to go, too. Depending on the type and thickness of the lacquer as well as the power of your heat gun, it can take some time until the lacquer is ready to crack. Start to heat it up from a distance and not with the heat gun directly on the guitar, checking the temperature of the lacquer from time to time with one of your hands. Never put your hand directly under the heat gun! Take the guitar body and your hands away from the gun when you check the temperature. If you feel that it’s not hot enough, keep heating it up until it’s good to go.
There are no rules set in stone because it depends on the things mentioned above. So, you have to try and see what works on your guitar. If you think the lacquer is hot enough, take away the heat gun and immediately spray the heated area with the cooling spray to create a sudden temperature gradient. You’ll likely have to repeat the process several times until the lacquer starts to crack, and usually you can hear when it cracks, which is a good sign. Work your way all over the guitar and crack it area by area. I needed approximately 90 minutes and four bottles of cooling spray until I was finished (Photo 3).
Does it look the same as cracked nitro lacquer? No, it’s not the same cracking pattern because of two reasons. On a nitro-lacquered guitar, the cracking happens because the softener disappears over time, which is a completely different thing. Poly is hard as glass and will never lose its softener. So, the vintage guitars of the future, let’s say in 100 years from now, will look much different compared to today—no more cracks. The second reason is that only in the middle of the spray is the lowest possible temperature not on the edge of the spray. But it’s the same ballpark, so don’t worry.
After you’re done with the entire guitar, let it cool down for some time before we start to make the cracks more visible. Again, there are different ways to do this. I prefer to use a strong black tea or coffee. Warm up the guitar slightly and dip some paper towels into the black tea or coffee before covering the guitar with them. Let them sit there for some hours before you remove them. The moisture will creep into the cracks, coloring them slightly, so they are more visible. This is a permanent process: The cracks will not lose their color again over time. On poly-lacquered guitars, I’ve also seen and tried alternative methods like using Coca-Cola, potassium permanganate, coffee grounds, stains, and more. The tea/coffee method works great and with good results and is, of course, harmless. But feel free to try other methods if you want to experiment, there’s no law against it.
After removing the paper towels, let it dry for some time before removing any residues from the lacquer using a dampish paper towel. Then, heat up the guitar slightly and let it cool down again. And voila, done! You can see the cracks are now brighter in Photo 4.
Congratulations, we are only one step away from finishing our aging project! Next, we’ll add some dings, dongs, and scratches, which is a lot of fun and a great way to individualize your guitar.
That’s it for now. Next month we’ll do another cool guitar mod, so stay tuned. Until then ... keep on modding!
Teatime: How to Age Wood at Home
Matthias Meyer of Bassart Guitars
Hi PG readers,
Did you ever wonder how it’s possible to add a special gray and dark color to the exposed wood on aged guitars? Here is my recommendation for how to do this with some simple household stuff you already have.
You will need: vinegar essence, water, black tea, steel wool, paper coffee filters, and some jars.
First, twitch a good handful of steel wool and put it in a jar. Next, fill up the jar with vinegar essence, close the jar, and let it sit for one or two days. The reaction of the steel wool and the vinegar will result in iron(II) acetate, which you can use as a dye. Use a cone-shaped paper coffee filter to percolate the liquid into a new jar and you hold the panacea in your hands. By adding some water, you can mitigate the dying effect and it’s easy to make some different aging dyes this way, from very dark to light gray.
Now it’s teatime. Make a strong black tea by using 6 to 8 tea bags in a pot, let it cool down, remove the tea bags, and pour the tea in a new jar.
One way of aging the exposed wood is to use the tea first, immediately followed by the iron(II) acetate (wet on wet technique). For a different effect and color, use the tea first and let it dry before applying the iron(II) acetate. Or use both liquids individually without the other one. It all depends on your personal taste and, of course, the wood itself. Before applying these liquids directly to your precious instruments, you should try to practice the process on some wood scraps you have lying around. Different woods react in very different ways and often the aging process needs one or two days before it becomes visible.
I hope you enjoy experimenting with this process. Cheers!
—Matthias “Matti” Meyer
Luthier Dave Helmer shows you how to cure buzzy strings, bad intonation, gnarly frets, high action, and other common troubles with off-the-shelf axes.
Guitars are the best. We love them. It’s fun to fall in love with a guitar at a store, buy it, and proudly bring it home. But we’ve all been there … where after a month that new guitar is just not playing as good as it was before. As guitar players, we know what feels good and what feels bad when it comes to playability. Maybe you have setup preferences that you like on all your guitars, or maybe you want to experiment with changes to your setup?
With a few tools, you can perform a handful of tasks that will make your new axe play better and stay in tune. This article is for folks who already know how to tighten loose parts, raise and lower string saddles or bridges, and adjust their truss rods—though I’ll share a tip on how to check it with even more accuracy.
Is that big bulky stock nut uncomfortable on your hand? Let’s trim it down and reshape it. If the action feels high and the neck looks straight, I’ll show you how to lower the action. And haven’t we all swapped out pickups and wondered, “Do they really sound better, or do I think that just because they’re new?” Before you swap your pickups, I’ll share some pickup-height measurements that might make you change your mind.
But wait! There’s more. With everything feeling and playing great, does moving into the upper register start to sound out of tune? Intonation is very easy to check and adjust. When you go to vibrato or hold a note, do the frets feel “sandy”? Are the fret ends rubbing against your hand while you play? Let’s flush and polish those up.
To be clear, we’re not swapping out anything on your new guitar: We’re simply refining the setup. Be sure to go online to see eight videos I made showing various processes covered in this story.
Begin the Beguine
There is an order of operations for best results. Neck relief is the first item to dial in, followed by getting the nut slots cut to the proper depth. After that, setting your string and pickup heights is in order. The final step is setting intonation.
Fret polishing is its own event and can happen anytime between string changes. Getting the frets feeling comfortable and well-polished will take some time and attention. You’ll also need some specialized tools as well as some that can be found in most households. Check the box for my list.
Tools You’ll Need
All of the specialized tools in this list are available through online suppliers, including StewMac and Amazon.
- 6" Ruler with measures in 64ths
- String action gauge [Photo 1]
- Miscellaneous screwdrivers
- Allen wrenches
- Radius blocks
- Understring radius gauges (with the radius on the bottom and the top)
- Fret-end dressing file
- Micro-Mesh sticks [Photo 2]
- Tape (low tack)
- Cotton swabs
- Paper towels (blue shop towels preferred)
- Clean cotton rags
- Nut files [Photo 3]
- Stikit sandpaper
- Tri-Flow lubricant
- Feeler gauges
- Simichrome polish
Polishing the Frets
Let’s start with the most Zen of these tasks: fret polishing.
Tape off the fretboard using low-tack tape, exposing only the frets. De-tack each piece of tape on your clothing or maybe a rag—I use my jeans or my sweatshirt. Making it less sticky helps prevent pulling finish off a maple fretboard or the neck. Taping the fretboard also prevents putting any cross-grain scratches into it while you file and polish. You can choose to tape off the entire fretboard or work your way down one fret at a time. Dealer’s choice.
One thing to note about tape, any tape: Even when you de-tack it, you do not want to leave it on overnight. If that happens, rub the tape with your finger, which will break the surface tension. Then carefully pull the tape off from a corner, making sure you’re pulling it off at an angle and not at a straight line with the fretboard edge.
Every fret end has a small burr on the corner from the initial fret job. The fret-end dressing file has a non-marring smooth side for rounding the fret end, and a safe square edge for getting into the corner of the fret end. So, take the fret-end dressing file, use the squared off-side, and file both corners of the fret end [Photo 4].
How to Polish Frets
Here’s how easy it is to polish and smooth frets.
One or two strokes is all you’ll need. Then, using the non-marring side of the file, slightly round off the fret ends. [Photo 5].
With the file positioned vertically, file downward to make the fret end flush with the edge of the fretboard [Photo 6].
For a nice, rounded-off look, polish the frets using the same rounding motion from the previous step, working through all three grits of the Micro-Mesh stick [Photo 7].
Photos 8 (top) & 9 (bottom)
Then, polish both the sides and the top of the frets [Photos 8 and 9]. Using a soft cloth and Simichrome, buff every fret. This will give you a great shine and help prevent oxidation. Now it’s time to remove the tape and condition the fingerboard if it needs it.
Note: Every fret has two fret ends to clean up and polish along with the fret itself. This is a fair amount of handwork. If you’ve never done it, you will get tired and need a break. Take that break. Take multiple breaks. Let the process take however long it requires without rushing. If you’re new, do all the fret polishing over a weekend or a few days. It should be fun, not painful. If it is difficult, call your local luthier and hire them to do it for you.
Adjusting Neck Relief
Neck relief refers to the slight amount of concave bowing intentionally created in the neck of a guitar or bass by adjusting the truss rod. For the safety of the guitar, be sure to slack the strings before doing any adjustments to the truss rod. Neither you nor your guitar needs to be tense during this process.
Before whipping out an Allen wrench for the truss rod, start by sight-checking the neck’s straightness. You can sight the neck with the guitar on its back, but I like to put it on edge and look at it that way. It’s easier to see how much curve there is when the guitar is on its side. I feel like gravity plays tricks on my eyes when I sight the neck with the guitar on its back. When I play the guitar, it’s on its side anyway, so looking at it from this vantage point is best [Photo 10].
Tune the guitar to pitch, put a capo on the first fret, and press fret 15 with your left hand. With your right hand, take a feeler gauge and check the gap at frets 7 through 9 (left-handed players, flip your hands around) [Photo 11].
From the top of the fret to the bottom of the string, the gap is usually anywhere from .003" to .012", depending on the feel you are going for. The feeler gauge should fit just between the top of the fret and the bottom of the string. The string shouldn’t move. This will tell you how much “relief” is in the neck. If you find this challenging, keep going—this will take some practice.
When dialing in the relief, I go back and forth between adjusting the truss rod and the string action. Getting the strings low and playing clean on a budget axe can be a challenge. Usually the fretwork isn’t that great, and in the upper register the frets can be unlevel, causing buzzes and clanks. If you need to raise the string action to get the notes to play clean, some fret leveling may be in order. (For more on fret leveling, go online to our article “About Fret Leveling,” from the December 2007 issue.) For good energy transfer, the neck should be as straight as possible. If the neck is straight and the frets are not level, the strings will buzz with low action.
In general, the flatter the radius on the fretboard, the straighter you can get the neck with the truss rod adjustment. On a fretboard with a 12" radius, you should be able to get .005" relief, and on a vintage 7.25" radius board you may need as much as .014" relief. The only way to get better at checking and setting relief is practice.
Refining the Nut
String buzzes, pinging noises when you tune, strings sticking in the slots, and too much string motion in the nut slots are all indicators of trouble. Before getting out the sandpaper and Micro-Mesh sticks, be sure you know if your guitar’s nut is TUSQ or bone. TUSQ is softer, so you should leave TUSQ nut slots a little higher. This leaves room for the TUSQ to wear without causing buzzing on the first fret. With bone, you can cut the slots lower, because it holds up to string wear.
How to Shape Your Guitar's Nut
Watch as Dave Helmer sands down the back half of a nut and creates a smooth finish.
The back side of the nut is usually very bulky and could often stand to lose some material to be more comfortable on your hand. So, let’s start there. Tape off the neck and headstock around the nut using a few layers of tape to protect the headstock face and fretboard. Then, slack the strings and pull them to either side of the nut.
Sand a bevel into the backside—the side closest to the headstock—of the nut using P320 and P400 grit Stikit sandpaper on a flat sanding stick. The bevel should start at the back of the nut and come forward about one-third to one-half the thickness of the nut [Photo 12]. Use P320 for most of the sanding and switch to P400 for the last 5 to 10 strokes.
Next, take a fresh Micro-Mesh stick and work through the various grits to buff/round over the bevel you’ve sanded into back of the nut [Photo 13], so it looks and feels good.
Photos 14 (left) & 15 (right)
TUSQ nuts are often tall, and the strings sit deep in the slots. Wound strings require 50 percent of the diameter of the string to sit in the nut slot, with the other 50 percent above the top of the nut surface. The plain strings should be flush with the top of the nut. Take a look at the wrong appearance [Photo 14] and the correct look [Photo 15] for properly seated strings.
How to Sand Your Guitar's Nut
Our luthier shows you how to use a radius block and sand down a nut.
Use a radius block that matches the radius of your fretboard. With P320 and P400 grit Stikit sandpapers, use mild pressure to sand down the top of the nut. Sand a bit and check your progress by setting the strings in the slots and putting a little tension on them. Tuning to pitch isn’t necessary. Use the P320 for most of the sanding, and switch to P400 when you are close to the 50/50 height for the wound strings. The radius block sanding will leave a flat, sharp edge on each side of the TUSQ nut [Photo 16]. To round over the sharp edge, use the sanding block and Micro-Mesh stick.
Use the coarse grit of a Micro-Mesh stick to round over and blend the bevel from the back into the top of the nut. Work through the grit gauges until it’s smooth. There is a fine balance between the bevel at the back of the nut and the top radius of the nut. Go back and forth between the two steps to get a nice, finished look and a nut that functions at optimal levels.
… And Refining the Nut Slots
Nut height is the distance from the top of the first fret to the bottom of the string. A good height on the wound strings is about .020", and for the plain strings about .015". Measuring this gap with a feeler gauge can be tricky because of the fretboard radius. Many repair folks do this by eye and feel, based on experience. It takes some practice. A good check: At pitch, fret the third fret and check for a small gap between the string and the top of the first fret.
How to Widen Your Guitar's Nut Slots
A diamond file can make quick work of deepening and widening nut slots.
The bottom of the string should be sitting on the bottom of the front half of the nut slot [Photo 17]. File down each nut slot to its proper depth using the corresponding nut file. There are diamond nut files on the market in multiple sizes to accommodate many string gauges. Make sure to keep your strokes straight. The standard-toothed files have less sizes and usually require rolling them from side to side to get a well-fit string.
Next, using a proper-sized file, round over the bottom back half of the nut slots down, toward the face of the headstock and away from the strings. This will allow the strings to move freely during tuning or bending, while still having support from the front half of the slot.
How to File D and G String Slots on Guitar
The D and G nut slots require special attention on 3x3-style headstock configurations.
On guitars with 3x3 headstock configurations, the D and G strings need the back half of the slots feathered out away from the center, so the string has a direct path to the tuner post. Using a file that is one size bigger than the string and rolling it side to side on the back of the nut slot will give the string a straight path to the tuner post. Photo 18 is my illustration showing which slots need feathering.
Additionally, use pencil lead to lubricate the slots. Just get in there with the point of a pencil and mark the slot with its graphite. You might also put a drop of Tri-Flow on the front of the string tree. Tri-Flow will run down the string, so take a cotton swab or cloth to clean up any excess. Tri-Flow has Teflon in it, so you don’t need much.
Adjusting String Action
First, find your string height by measuring the string action at the 17th fret on a Fender-style guitar and at the 15th fret on a Gibson-style instrument.On electric guitars, action can range from 3/64" to 3/32", depending on the player’s comfort. My preferences are 1/16" on the treble side and 5/64"on the bass side on both Fender- and Gibson-style guitars measured at the appropriate fret.
How to Adjust Guitar Action
Here’s a look at how our author adjusts the action.
Always loosen the string tension before making action adjustments. This will save wear and tear on the small bridge components. Take either a 6" ruler or a string action gauge and set it on the frets. Measure from the top of the fret to the bottom of the string [Photo 19].
If the action is high, you will lower that string’s saddle or that side of the bridge. If it is low, you will raise it. Make sure the individual saddles are sitting square and upright to the face of the bridge. You do not want them sitting at an angle or leaning over. This will cause buzzing.
The bottom of the strings should match the radius of the fretboard when measured with an understring radius gauge [Photo 20]. Start your adjustment with the outside strings, working toward the center. On Fender-style guitars, set the two outside strings to the height you want and have the middle four strings a bit higher than that. Bring the gauge up from underneath and just touch the two outside strings. Then, bring the strings down a little at a time until the radius matches.
On a Gibson-style Tune-o-matic, the saddles are not individually adjustable. So, if the radius doesn’t match, the saddles will need to be filed. To do this, I recommend using toothed nut files and a rolling side-to-side motion. Do a little work and check your progress. Remember to slack your strings when adjusting the saddle or bridge up or down.
Changing Pickup Height
Finally, let’s take a look at pickup-height adjustment. First, to check pickup height, use the two outside strings again. Press the top wound string on the last fret and measure the distance from the top of the pole piece to the bottom of the string [Photo 21]. This distance can range from 3/64" to 1/8". My preferences are 1/16" on the treble side and 5/64" on the bass side.
Adjusting Guitar Pickup Height
Dave Helmer walks you through the process of adjusting the height of your guitar’s pickups.
On most styles of pickups, there are height adjustment screws on either side of the pickup to raise or lower it. The closer the pickup gets to the strings, the more present string frequencies become. If you get too close, the magnetic pull can affect the string’s vibration and you may hear some strange sounds as you go into the upper register.
On Strats, the neck pickup is regularly set too close, and at the 12th fret and above, the low E and A can sound choked, honky, and not clear. Lowering the neck pickup with a screwdriver usually solves this issue.
If you can’t get your guitar accurately in tune, you might need to check its intonation. Adjust all saddles as far back as possible so every string will play flat at the 12th fret. You will adjust the saddles forward, gradually making the octave play sharper until it’s in tune with the open string [Photo 22].
Adjust Your Guitar's Intonation
With a tuner and a screwdriver, Dave Helmer shows you how to adjust your guitar’s intonation.
Depending on your vibrato style, experiment with intonating the plain strings slightly flat. Use your ear and do what sounds good. Sometimes, the plain strings can have perfect intonation, but playing with vibrato can make them sound sharp.
To fine-tune intonation, the individual bridge saddles must be adjustable. Once the intonation is set, recheck the string radius using the understring radius gauge and adjust as needed. The radius can change as the saddles come forward during intonation.
Tri-Flow is great for lubricating saddle parts. Put a small drop on the saddle-height adjustment screws and capillary action will suck it in. Adjust the saddle up and down a few times to coat the threads. Clean up any excess with a cotton swab or cloth. Put a drop or two onto a cotton swab and apply the Tri-Flow to the top of each saddle where the string rests. This will help strings move freely during tuning and after any bends or vibrato.
And that’s it! For a relatively small investment in tools and time, you’re now ready to supercharge your new guitar—and maybe your long-treasured axes, too.