7. Protect the top around the fingerboard.
I like to lay on a section of 5” wide low-tack masking tape, and tape a sheet of .005” steel shim stock over the wide tape. The wide tape Stewart-MacDonald now sells is perfect for the job -- low tack and not likely to lift even delicate old finish. The shim stock is easily cut with regular scissors, and will protect against a slip with fret saw or file. Here, I'm using some low-tack blue masking tape I found at a surplus shop:
8. Heat & remove frets. I hold the soldering iron on the fret for about 10 seconds and bite under the fret with flush cutting end nippers. When the fret is hot enough, the cutters lift it easily with a little pressure. I slide the iron along, heating the fret as I bite under it with the nippers. The nippers tend to hold chips down against the fingerboard. If the fret is particularly obstinate, or the fingerboard is very flaky, I have a second pair of nippers ground dull, so I can give a second “bite” to raise the fret out gently. I’m not pulling upward, just squeezing the nippers to wedge the fret up and out.
If you look closely, you should be able to make my fret pulling nippers and the soldering iron just behind:
As I reach the other end of the fret, it should come out cleanly:
If all went well, I have removed the frets without pulling up any chips of fingerboard. If the frets didn’t come out cleanly, then it’s time to glue down the chips. I leave the chip in place, and run thin superglue under it. I spray superglue catalyst (accelerator) on a broad putty knife, and using firm pressure, “iron” the chip in place. Keeping the knife moving and pressed down, I avoid sticking the knife to the fingerboard. I’ve found that it is much easier to clean out the small amount of glue that might run into the slot than it is to prevent the spill, so I just ignore that problem for now.
Sometimes tiny chips fall out and disappear. I fill these little holes with medium viscosity superglue mixed with a bit of the appropriate color dust or lampblack. A little catalyst dabbed in the hole ahead of the superglue helps the fill harden very quickly. (Catalyst applied on top of the superglue is more likely to cause the fill to turn white in spots.) In any case, I glue back all chips before starting to sand the fingerboard level, even if the filled areas are eventually to be sanded through.
These frets came out quite well, leaving only little trails at the very edge of the fret slots where the barbs on the fretwire tang pulled through:
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