Have you ever wondered how precision holes in metal parts are perfectly threaded?
Taps are the unsung heroes in machining, essential for creating internal threads. But not all taps are created equal.
In this article, I’ll introduce you to the four commonly used types: Spiral Fluted Taps, Spiral Pointed Taps, Fluteless Taps, and Straight Fluted Taps.
What are Spiral Fluted Taps?
Spiral Fluted Taps are known for their spiral grooves. They’re designed to eject chips upward and are ideal for blind holes.
Features and Applications of Spiral Fluted Taps
Features
・Spiral flute
・Chips flow out against tapping direction (ejected from holes)
・Lower tapping torque and applicable for tapping to the bottom of holes
・Good cutting action
Applications
・For blind holes
・Materials where chips come out continuously in coil shape
These taps are perfect for materials that produce long chips, like aluminum and stainless steel. Their design reduces friction and increases the tapping speed.
What are Spiral Pointed Taps?
Spiral Pointed Taps have a pointed end that drives chips forward, suitable for through holes.
Features and Applications of Spiral Pointed Taps
Features
・Spiral point(Chip Drive)
・Pushes chips forward with low cutting torque
・Shallow and unique flute form provides strong structure
・Good cutting action
Applications
・For through holes
・Materials where chips come out continuously in coil shape
・High speed tapping
They are great for materials that create stringy chips. The design allows for faster tapping with less resistance.
What are Fluteless Taps?
Fluteless Taps, or Forming Taps, deform the material to create threads without cutting, leaving no chips.
Features and Applications of Fluteless Taps
Features
・Fluteless
・Taps do not produce chips
・Precise uniformity of tapped thread limit
・Excellent rigidity
Applications
・For both through & blind holes
・Materials with Formability
Ideal for ductile materials like copper, these taps produce stronger threads and are highly durable.
What are Straight Fluted Taps?
Straight Fluted Taps are the traditional taps with straight grooves, mostly used manually for precision.
Features and Applications of Straight Fluted Taps
Features
・Straight flute
・Strong cutting edges
・Applicable for various cuttig conditions
・Easy to re-grind
Applications
・For both through & blind holes (short thread depth only)
・Materials where chips come out in powder form
・Hard materials
They are best for short-run, manual threading in softer materials or for repair work.
Comparing the 4 Types of Taps
Each type of tap has its unique applications and advantages, based on material and hole type.
Decision Factors: Choosing the Right Tap for Your Needs
Consider the material, hole type, and the desired speed and finish when selecting a tap.
| Tap Type | Application | Material Characteristics | Hole Type |
|---|---|---|---|
| Spiral Fluted Taps | Lower torque, bottom-hole tapping | Long, coiled chips | Blind holes |
| Spiral Pointed Taps | High-speed tapping, chip forwarding | Continuous coil chips | Through holes |
| Fluteless Taps (Forming Taps) | Chipless threading, uniform threads | Good formability, displaces rather than cuts | Both through & blind holes |
| Straight Fluted Taps (Hand Taps) | Versatile, easy to re-grind | Powder-form chips, hard materials | Both through & blind holes (short depth) |
How to extend the service life of taps
Maintaining and extending the service life of taps is crucial in CNC machining, and one of the key factors in achieving this is the proper use of lubricants.
- Choosing the Right Lubricant:
The choice of lubricant depends on the material being tapped and the type of tap.
For example, for tapping softer materials like aluminum, a light, mineral-based oil is often sufficient. For harder materials like stainless steel, a heavier, sulfurized oil may be necessary.
Water-soluble oils are also popular due to their cooling properties and ease of cleaning.
- Consistent Application:
Ensure consistent and adequate lubrication during the tapping process.
The lubricant should be applied directly to the tap and the workpiece before and during the tapping operation.
This helps in reducing friction and heat, which are major causes of tap wear.
- Using Emulsions for Cooling:
In high-speed tapping or with materials that generate a lot of heat, using an emulsion (a mixture of oil and water) can be beneficial.
The water content helps in cooling, while the oil provides lubrication.
- Cleaning Taps Regularly:
After each use, taps should be cleaned to remove any metal particles or residues.
This can be done using a brush and a cleaning solvent.
Regular cleaning prevents the build-up of materials that can lead to increased wear and tear.
- Proper Storage:
Store taps in a clean, dry place, ideally in their original cases or a dedicated storage system.
This prevents them from coming into contact with moisture, dust, and other contaminants that can cause corrosion or damage.
- Using Lubricants with Additives:
Some lubricants come with additives like sulfur, chlorine, or phosphorus, which can provide extra protection against wear and tear, especially for taps used on tough materials.
- Monitoring Lubricant Condition:
Regularly check the condition of the lubricant.
Over time, lubricants can become contaminated with metal particles or lose their effectiveness due to breakdown.
Change or filter the lubricant as needed.
- Temperature Control:
In some advanced setups, maintaining a consistent temperature of the lubricant can further enhance tap life.
Cooler lubricants generally improve tap longevity by reducing thermal stress.
Conclusion
The right tap can make all the difference in precision machining. Whether it’s Spiral Fluted, Spiral Pointed, Fluteless, or Straight Fluted Taps, understanding their specific applications enhances the quality and efficiency of our work.
At Santanoo, we’re committed to not just providing top-notch machining services, but also sharing our expertise to help you make informed decisions for your machining needs.
