MIMF

I've bound a fretboard with a darkish wood, similar in shade to the neck wood. To set it off I'd like a thin white purfling type line between the board and the neck. I should have thought of this before and attached it to the binding, but didn't. Now I'm thinking that if I glue a sheet of fiber veneer between the board and the neck, the reveal will be the thin line.
My question is, will the sheet of fiber (0.010") be a weakness that might cause the fretboard to separate from the neck at some point? Unless someone here knows, I'll do a test on scrap and tear it apart to see where it breaks.

Why not rout a small recess in the bottom of the edge of the fingerboard, say 1/4 inch wide, and deep enough to take the veneer or fibre. glue it in at same time as you glue fingerboard. I did this on my last one and it works well

The fiber is plenty strong, especially for such a large joint.

Thanks Bob and Barry. I hesitate to try to route it hand held as it's already slotted and radiused, so maybe a good excuse to mickey-mouse a routing table. If it fails, then I can just glue it with a sheet of fiber. But it will be awhile - I still have to do the head stock before I attach the fret board.

If you're worried about the fiber not holding you could sandwich a piece of maple veneer between the fretboard and neck. That would be a nice contrast and keep it all wood.

Thanks Ryan - that's a good alternative. I took Bob's suggestion to heart and made a very simple routing table using a generic workmate stand. The fence pivots on a screw and clamps on the other end.
This test piece has a 1/4" wide by 0.012" depth like I will do on the fretboard, but that again will be awhile until I get the headstock done.