I’ve lived with an annoying string buzz on my AR371CE archtop since I bought the guitar six years ago. I should have taken it to a luthier but never got around to it. If your guitar buzzes only on certain strings when playing only in certain positions, it might be due to a high fret or two. The intelligent solution is to take your guitar to someone who knows what they are doing. But if you, like me, sometimes lack that common sense, here’s what I did to fix my buzzing and what I would do differently in the future.
The first thing is to diagnose the problem. There are many reasons for buzzing and not all of them have anything to do with your fret height. A fret rocker is a great tool to see if a fret is too high compared to its neighbors. But I’ve used the StewMac string height gauge and I’ve seen videos of people using credit cards. You need a tool with a straight edge that spans 3 frets but not four. The StewMac style fret rocker has four unequal sides that can be used on ukuleles to basses.
I already knew two of my frets were high in spots but not on all strings. A fret rocker was still essential to monitor the progress when I decided to fix this myself. If I had needed extensive fret leveling and re-crowning work done, I would not have attempted this myself. But I felt moderately comfortable working on two frets.
StewMac has a video describing all of the different types of files they sell for fretting. Many of their files are for special purposes, for example for leveling frets before crowning or crowning frets after they have been leveled. Others are multipurpose such as the three-corner file favored by many luthiers.
The first mistake I made was to purchase inexpensive copies of StewMac tools from Amazon. A set of fret tools I purchased cost me under $15. It would have been over $75 from StewMac for better quality and better-designed items. My rationale was I doubted I will have level frets of any of my instruments ever gain. This is the first time I thought it necessary to fix a string buzz by leveling a fret in the nearly sixty years I’ve played guitar. If I were going to do this for a living or even occasionally (for example because I was buying new instruments) I would go for the quality. That said, the only tool I would definitely go for would be the StewMac three-corner file. (I’ve owned several three-corner triangular files but all but the smallest nut files were lost or given away when I sold my shop tools before moving south. Although you can buy a triangular file from a home or hardware store, the edges of the StewMac files have been ground smooth so you don’t accidentally gouge your fretboard or an adjacent fret).
The inexpensive fret kit I bought had a fret rocker, two polishing stones that I used in place of a file for leveling, string spreaders, and fingerboard protectors. Those were all adequate even if the StewMac items were better. The kit also included a crowning tool which I decided not to use after I examined it.
I checked the relief on my neck and made some adjustments to the truss rod before I did anything else. I set the truss rod so the neck was nearly flat with just a bare hint of relief.
I used the Fret Rocker to identify where high frets are located. I used a marker to indicate which frets were high and under which strings since only the second through fourth-string were off. I worked from the lowest high fret to highest, doing one at a time.
I should have marked the position of the floating bridge with masking tape. Because I didn’t do this, the bridge moved while I was working on the frets and I had to reset the bridge placement and intonation when I was done.
I loosened the strings but did not remove them. The loose strings allowed the floating bridge to move out of position.
I used the String Spreaders I bought to move stings out of the way of the area were high frets are located
I used a combination of masking tape and metal fret protectors (Fingerboard Guards Protectors) to protect fingerboard while filing the frets
If I were to do this often (or ever again) I would get a StewMac triangular file. However, of the tools I had, I used the two grinding stones to file the top of the frets, checking frequently with the Fret Rocker to see if I had removed enough from the top of the fret.
I did not like either the Fret Crowning File that came in the Fashionroad kit. I used the grinding stones instead. This is where the triangular file would have done the same job.
I marked the top of the fret with a marker and attempted to round the fret with the above tools. The goal is to remove all but a narrow band of the blue mark from the fret, leaving the “landing area” (very top of the fret that is marked) so no additional material is moved from where fret has been leveled. In practice, I had a difficult time seeing if I had removed enough or too much because of Macular Degeneration vision impairment.
I used a series of Micro Mesh Soft Sanding Pads from 1500 and working up to smooth the rough frets after crowning as above.
I also adjusted the pickup height, lowered the action and reset the position and intonation of the floating bridge.
When done, the AR371 played much better. The major buzzing problems are fixed.