Official Luthiers Forum!

If you want to put a large shell inlay into a fingerboard, how do you cut through it to open up the fret slot? ...Jeweler's saw? ...fret saw? ...and how do you put in the fret without cracking the shell?

A fret saww will work if in good shape. Personally I plan for where possible and make that piece in two pieces. but it is common to inly prior to slotting the fretboard and slotting through the inlay

Here's where cnc really shines. You can cut the pocket for the inlay just shy of the fret slot, so that the shell or inlay comes only within a hair or two of the slot, yet is still covered by the fret. This way, the fret tang is seated against the fretboard and not the pearl, which will also make removal & replacement of the fret easier someday.
Without cnc, I like Michael's idea of planning for the slot when cutting the pearl so you don't have to cut through it.

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

What Michael said. To avoid cracking the pearl, make sure you use a triangle or square file to chamfer the slot / fingerboard top edge well (which you should do on all the slots anyways), and don't press or hammer the fret in too firmly and you shouldn't have any problems.

<edit> Don, CNC is cheating

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Rian Gitar og Mandolin

If you must cut across an inlay,it's best to camfer the edge before you press the fret in to keep from chipping the inlay.And be very carful to not put too much pressure on the inlay as well.Shell is very brittle and can crack or chip when fretting the board.It's best to not sit the fret on the inlay if possible.It's also important to use well seasoned fretboard material as the shrinking of the wood can raise and crack large inlays as well.

If you saw through it use a fret saw that is small not that big saw that StewMac sells for slotting boards. Use one that's like a razor saw. Start your sawing so that you are sawing off the shell at the point across the board or the back edge. Not the front edge or you will chip or crack it or pull it up. Do only forward strokes and whipe the saw blade after each stroke with a rag or paper towel to remove any chips from the saw teeth as that can cause the saw to bind. Go slow and steady being careful to not let the saw slide so don't go to hard. You don't want to mess up the shell at this point of the game and don't force it. Besides tapering the slot you can flatten the barbs on the fret tang where they meet the shell. If the shell is wide and you have to flatten alot of barbs then glue in the fret with CA or hide glue. I also fill the fret slot with johnsons paste wax before gluing the inlay so the fret slot doesn't fill with CA and make it even harder to slot and the wax helps with the sawing some when through the shell.