Sheet metal screw

1. A sheet metal screw, comprising:

a head end, an entry tip end and shank running between the head end and the entry tip end,

wherein the shank includes a first portion that runs from proximate the head end and toward the entry tip end and includes a self-tapping thread, and a second portion that runs from the first portion to the entry tip end and forms a self-drilling tip that is unthreaded, wherein the shank includes at least one flute on the self-drilling tip,

wherein a base diameter of the shank along the first portion is a substantially uniform diameter, and

wherein a base diameter of the shank along the second portion reduces in size when moving from the first portion toward the entry tip end to such that the self-drilling tip is defined as a tapered self-drilling tip;

wherein a taper angle of a primary portion of the tapered self-drilling tip is between five degrees and twenty-seven degrees;

wherein the at least one flute runs from the entry tip end, along the primary portion with the taper angle and toward the first portion of the shank;

wherein the self-tapping thread begins proximate the head end and extends toward the tapered self-drilling tip;

wherein the self-tapping thread includes a thread edge defined by a symmetric thread angle of between thirty and forty-eight degrees, and the thread edge is continuous and follows a trilobular thread edge profile in end view;

wherein the self-tapping thread is a double lead thread;

wherein the head end defines an enlarged head with a lower surface facing the entry tip end,

wherein the shank has the substantially uniform diameter at a location of joinder of the shank with the lower surface of the enlarged head;

wherein an entry tip segment of the tapered self-drilling tip is defined by an entry taper, and the entry taper is between one-hundred five and one-hundred fifteen degrees.

2. The sheet metal screw of claim 1 wherein an axial length of the entry tip segment is no more than twenty percent of an axial length of the tapered self-drilling tip.

3. A sheet metal screw, comprising:

a head end, an entry tip end and shank running between the head end and the entry tip end,

wherein the shank includes a first portion that runs from proximate the head end and toward the entry tip end and includes a self-tapping thread, and a second portion that runs from the first portion to the entry tip end and forms a self-drilling tip that is unthreaded, wherein the shank includes at least one flute on the self-drilling tip,

wherein the head end defines an enlarged head with a lower surface facing the entry tip end, wherein the shank has a substantially uniform base diameter along the first portion, including at a location of joinder of the shank to the lower surface, and

wherein the shank has a reducing base diameter along the second portion when moving from the first portion toward the entry tip end to such that the self-drilling tip is defined as a tapered self-drilling tip;

wherein a taper angle of a primary portion of the tapered self-drilling tip is between five degrees and twenty-seven degrees;

wherein the at least one flute runs from the entry tip end, along the primary portion with the taper angle and toward the first portion of the shank;

wherein the self-tapping thread begins proximate the head end and extends toward the tapered self-drilling tip;

wherein the self-tapping thread includes an asymmetric thread angle;

wherein the self-tapping thread includes a thread edge defined by a leading flank angle of between twenty and twenty-five degrees and a trailing flank angle of between ten and fifteen degrees, and the thread edge is continuous and follows a trilobular thread edge profile in end view, facilitating sheet metal penetration, and wherein the self-tapping thread is a double lead thread;

wherein an entry tip segment of the tapered self-drilling tip is defined by an entry taper, and the entry taper is between one-hundred five and one-hundred fifteen degrees.