Think & Tinker, Ltd.
CNC router bits and carbide cutting tools with tutorials and technical guides
We will be closed Nov. 23 and 24.
Have a Happy Thanksgiving.

Todd Reith

(Reith Guitars, Custom Luthier)
Reith Guitars is only about 25 miles north of our Colorado facility in Palmer Lake. Ironically, it has only been within the past year that Todd has started incorporating PreciseBits into his production processes. During that time, he has helped us refine the design of some of our existing tools and has been instrumental in the creation and testing of tools that are only now starting to show up in our catalog. Many of Todd's designs that incorporate mother-of-pearl (MOP) or other shell products require to use of tools much finer than our standard 0.0313" dia. shell cutter.
Chevy emblem
Seen from the side, this stylized Chevy emblem clearly shows the multiple passes used to cut down through the 0.0625 in. (1.59mm) thick MOP. Since none of the inside corners required a small radius, Todd used a 0.0313" MOP cutter*.  His cutting strategy was to run his spindle at 24KRPM and plunge 0.020 in. (0.5mm) into the shell with a 6 in./min. (153mm/min.) infeed,
  1. cut the first pass at 12 in./min. (305mm/min.),
  2. plunge 0.020 in. (0.5mm) deeper,
  3. cut the second pass...

This process would be repeated until the part was cut from the surrounding material

* MS3I8-0313-010F 3-flute chipbreaker shell cutter

From here things get a bit more dicey. Part of the design demanded engraving characters with a stroke width of 0.022 in. (0.5mm). Since the 0.022 in. bit* is only 35% as strong as the 0.0313 in. tool used above, a far more conservative cutting strategy was called for. To engrave the "MILE CLUB" in the "wings", again using 24KRPM, the cutter was plunged 0.010 in. (0.25mm) deep at 5 in./min. (127mm/min.) infeed, then he
  1. cut the first pass at 10 in./min. (254mm/min.),
  2. plunged 0.010 in. (0.25mm) deeper,
  3. cut the second pass...

This process would be repeated until the the characters were carved to the desired depth.

* MM3I8-0220-009F 3-flute fret cutter

Chevy emblem pocket
Notice how well the Chevy emblem fits into the pocket cut into the wings.
 Just enough space to allow glue to seep out as the "cross" is pushed into place.
About as close to "zero glue line" inlay as you can get!

Chevy emblem pieces
individual pieces of the pattern
All of the pieces that would be inlaid into the finger board are shown at left. The larger Chevy "cross" figure at the bottom would be used as fingering dots  and the assembled/filled logo would be inlaid at the top of the fingerboard.    Inlaid into fingerboard
logo inlaid at top of fingerboard