Straight flute reamers can be very helpful and important in our work.
They help us on keywork, machining parts, modifying tools and more. They can be used to ream a key hinge that has an issue or to size it up for a larger steel (arbor). They can open the throat of a trumpet mouthpiece and have many other functions.
Straight flute reamers can be used either under power at low speed (in your bench motor) or by hand (in a pin vise or handle).
“Straight Flute” means that the flutes (the grooves that cut and clear material) are not spiraled, they run straight along the length. This reamer design is best for “through holes” (holes that go all the way through).
These cutting tools are used to slightly enlarge and finish holes to a precise size with a beautiful finish. Follow your twist drill with a reamer to bring a more perfect hole to a tighter tolerance.
Sizes 19 through 27 will work for most mouthpieces.