Screw Points & Thread Styles

Screws come in a variety of drive styles, thread styles, head styles and length to suit most fastening needs.  Today we will be looking into point/thread styles.

Point/Thread Styles

The point styles on a screw serve the purpose of tapping, cutting or drilling through the desired material. There are five main screw point categories:

1. Tapping screws – tapping screws get their name because they “tap” their own mating threads.  Some tapping screws require a hole while others are self-drilling. They are identified by a designation of its thread and point:

   1. Type A Point

   2. Type AB Point

   3. Type B Point

   4. Type BP Point

   5. Type 17 Point

2. Thread cutting screws – thread cutting screws are self-tapping screws that create new threads in existing holes.  Often used in wood and plastic.

   1. Type F Point

   2. Type 1 Point

   3. Type 23 Point

   4. Type 25 Point

   5. Type 17 Point

   6. Type BF Point

   7. Type G Point

3. Thread forming screws – thread forming screws provide a tighter hold because it mates with zero clearance.

   1. Tri-round Type TT Point

   2. Type C Point

   3. Type CA Point

   4. Type PT Point

   5. Type Hi-Lo Point

   6. Low Root Point

4. Self-drilling screws – Self-drilling screws eliminate the need for hole preparation.

   1. Self-Piercing Point

   2. Self-Drill Point

5. Machine & Tapping Screws – uniform threads designed to fasten into uniformly threaded nuts or threaded holes.

   1. Header Point

   2. Dog Point

   3. Rolled Point

   4. Pinch Point (rounded)

   5. Nail Point (pinched)

   6. Cupped Point

   7. Round Point

   8. Cone Point

   9. Type U Drive Point