In fastener design, the "point" of the screw is often an afterthought, but it is actually one of the most critical factors in how that screw interacts with the pilot hole at assembly. For TAPTITE PRO® fasteners, the choice typically comes down to two options: the Standard Point or the SP™ (Short Point).
Choosing the wrong one can lead to two very different headaches—either a screw that won't align or a joint that risks stripping because it lacks enough thread engagement. Here is how to make the right call for your application.
The Standard Point: Your Baseline for Success
The standard point on a TAPTITE PRO® fastener is engineered with a specific taper to act as a stabilizer. This point finds the center of the pilot hole and "self-aligns" the fastener before the thread-forming lobes begin their work.
However, the length of this taper isn't universal; it scales with the size of the fastener to ensure optimal lead-in:
- M5 and Smaller: These fasteners utilize a 4-pitch lead-in point.
- M6 and Larger: These fasteners utilize a 5-pitch lead-in point.
The Benefit: This geometry significantly reduces the "end load", which is the physical force required by an operator or a robot to start the screw. By providing a longer lead, it reduces operator fatigue and eases assembly.
When to Use It: A standard point should be your default choice for steel applications and through-holes or deep blind holes in aluminum. If you have the room for the point to protrude or sit deep in the hole, the standard point provides the most consistent, ergonomic assembly experience.
The SP™ (Short Point): Solving the Shallow Hole Problem
The SP™ (Short Point) is a problem-solver for specific engineering constraints in non-ferrous materials, where depth is at a premium. Unlike the standard point, the SP™ remains a constant length regardless of the fastener size:
- All Sizes: All SP™ fasteners utilize a 2.5-pitch lead-in point.
The Function: In a blind hole, every millimeter counts. A standard point might "bottom out" at the bottom of the hole before the screw is fully seated. The SP™ allows for maximum full-thread engagement in a much shorter distance.
The Benefit: By getting more full threads into a shallow hole, you increase the stripping resistance of the joint. This is particularly vital in soft materials such as aluminum or zinc die castings where thread depth is the primary driver of joint integrity.
When to Use It: Use the SP™ when you are dealing with shallow blind holes in non-ferrous materials.
The Trade-Off
Engineering is often the art of the trade-off. While the SP™ solves depth issues, it requires more precision during the initial start of the assembly. Because the "lead-in" is 40% to 50% shorter than a standard point, the initial alignment isn't as forgiving.
Summary: Which One Wins?
- Standard Point (4-5 Pitches): Choose this for ease of assembly, lower operator fatigue, and better alignment in through-holes or deep holes.
- SP™ (2.5 Pitches): Choose this to maximize thread engagement in shallow blind holes in non-ferrous materials.
Have questions on your application?
Be sure to contact us and we’ll be happy to optimize an engineering plan for your assembly.