09-13-2015, 07:33 AM
Hi Anthony,
I think the majority of commercial taps have ground flutes, for production it saves a step.
If you're milling the flute, I'd probably use the ball-end mill, the flutes would then have larger radii in the gulley, so less stress concentration (always a good thing!) where a regular endmill would put a corner / very small radius.
Thinking about the stresses applied to the tap, the bottom of the flute is where a stress fracture is likely to start before propagating helically along the tap, or at least that's how it's always looked to me, except when I've bust 'em by bending 'em...
After milling, you'll need to heat-treat the tap, I guess, that will probably leave the cutting edges in need of sharpening, a dremelloid with an abrasive stone or disc is a good low-budget way :)
I think the majority of commercial taps have ground flutes, for production it saves a step.
If you're milling the flute, I'd probably use the ball-end mill, the flutes would then have larger radii in the gulley, so less stress concentration (always a good thing!) where a regular endmill would put a corner / very small radius.
Thinking about the stresses applied to the tap, the bottom of the flute is where a stress fracture is likely to start before propagating helically along the tap, or at least that's how it's always looked to me, except when I've bust 'em by bending 'em...
After milling, you'll need to heat-treat the tap, I guess, that will probably leave the cutting edges in need of sharpening, a dremelloid with an abrasive stone or disc is a good low-budget way :)
Rules are for the obedience of fools, and the guidance of wise men...
(Douglas Bader)
(Douglas Bader)