In a recent post, I touched on the differences between guitars costing $300 and $6,000. Besides the obvious differences, which you can see such as components and wood, I tried to stress the elements that aren’t always visible to the untrained eye. Specifically, I mentioned the nut and the subject of today’s The Dirty Secrets Of Guitar Building…Part 5: the frets.
I could write a book about installing frets, but that has already been done. Stewmac.com has a great book on the subject. Instead, my goal is to impart some of the details I feel are of critical importance.
Let me start with the fretboard itself. To begin with, an accurate fret job requires a precisely shaped fretboard. Since most fretboards have a radius from side to side, it’s vital this curve be generated accurately. Most fretboards have a consistent radius meaning, for example, 12 inches at the nut and 12 inches at the heel. However, conical radii (where the radius may be 12 inches at the nut and 16 inches at the heel) are also popular. Regardless of the style, it has to be precisely generated. Otherwise, the frets will lay down uneven. It doesn’t necessarily take a lot of skill to generate an accurate radius, but it does take frequent checks with an accurate template(s) along it’s length during the sanding process to gauge your progress. Start by using a precisely shaped radius sanding block and 80 grit paper. Once you have the curve generated precisely, switch to 120 grit just long enough to remove the 80 grit scratches. Then, do the same with some 220 grit. Don’t spend too much time sanding after you’ve achieved the correct radius and removed the previous grits scratches. Too much sanding will deform the shape and require you to start over. Don’t rush this step or you’ll be disappointed the first time you strum the guitar.
My homemade fretboard radius jig.
Sanding blocks work well, especially after using the fretboard radius jig.
Sawing the fret wire slots. I have found that even though you may think your saw and miter box are up to the task, it’s imperative that you test their accuracy on some scrap wood. The slightest play between the blade and the slots of your miter box will result in crooked frets. Make sure the saw fits snug. Also, make ABSOLUTELY certain the fretboard doesn’t move from side to side as you slide it through the miter box. It should move so that each slot is exactly parallel to the one you just cut. I like to saw my fretboard blank into a perfect rectangle that fits snug into my miter box before I slot it. Then, I saw it into the final, tapered shape after cutting the slots. I find it much easier to slide a perfect rectangle through the miter box than it is to do the same with a tapered shape.
The depth of the slots is very important as well. Since the frets will follow the radius, the slot has to do the same. Obviously, it can be very difficult to saw a slot which is curved from one edge of the fretboard to the other. However, this isn’t absolutely necessary. As long as each end of the slot is as deep as the fret wire’s tang, the center will most likely be deep enough. I check this with a feeler gauge that has been marked with the tangs depth. Check both ends and the center. If at any point the slot is too shallow, the tang will bottom out and cause the fret to bulge up from the fretboard’s surface.
Choosing fret wire. Boy, I really like stainless steel fret wire. You can really pound it in to a slot without damaging its shape. And it lasts a long time. However, it works best if you can install frets evenly and consistently so that you don’t have to do any leveling and recrowning. That’s where a fretboard with an accurate radius and slots, which have been cut to the correct depth, comes into play. Otherwise, your only other choice is 18% nickle wire that can be dinged if you hammer too hard.
Installing the frets. Stainless steel wire needs to be radius’d to match the fretboard exactly. Nickle wire can vary a bit since it will usually conform nicely to the radius. To install the wire, you basically have two choices; pound or press. I like to press. The results happen faster and are less prone to dinging. You can buy an arbor press, or do as I have done and make your own. If you have to hammer, buy the proper tool. Don’t use grandpa’s big old claw hammer. You’ll end up destroying the frets. And get some extra wire to practice no matter how you plan to install the wire. Some people like to glue the fret wire into the slot. I don’t. If you use a saw blade that is about the same thickness as the fret wire’s tang (about .023 inches) it should remain seated just fine. But you should test on some scrap just to be sure.
My homemade fret press.
Fret dressing. Besides angling the edges and rounding them off slightly, I really hate to level and recrown my frets. This only applies to new necks since refrets usually require this step just to get the frets to match. I have found that if I do a good job of making the fretboard and its radius, I don’t have to do much in the way of leveling. I like it this way because when I buy wire, I choose it for its profile. Leveling changes that. To check the accuracy of your fret installation, make sure the fretboard is level first. You’ll do this by adjusting the truss rod.
To check if it’s level, use a straightedge that’s been notched to clear each fret. This approach allows you to rest the straightedge directly on the fretboard and not the frets themselves. If you rest the straightedge on the frets while adjusting the truss rod, you’ll get an inaccurate reading of which frets are high and which are low. You want to adjust them not only in relation to one another, but to the fretboard as well.
Use a straightedge like this one from stewmac.com to check and adjust the fretboard level.
If you radiused the fretboard accurately and did a really good job of installing the fret wire, you’ll have very little (if any) leveling to do. And in my opinion, that is the goal. Up next: Neck thru, set-in or bolt-on… Does it really matter? Stay tuned.
#1 by Alcirnei Oliveira on January 20th, 2010 - 10:39 am
Congratulation.