What pilot hole size should I use for small titanium threads (M2–M6)?

Enlarge titanium pilot holes 0.05–0.1 mm beyond standard to avoid tap breakage: M2 φ1.65 M3 φ2.55 M4 φ3.35 M5 φ4.25 M6 φ5.1. BJCJTi's workshop applies this rule across M1–M6 titanium threading ensuring smooth chip evacuation and consistent 6H-precision results for miniature fasteners.

What tap material and coating work best for titanium threading?

Use powdered high-speed steel (PM-HSS) taps with helical flutes for blind holes or straight flutes for through holes coating should be oxide DLC or AlCrN—never TiN or TiCN which increase galling on titanium. BJCJTi selects these tool specs to protect thread quality in small titanium alloy screws and bolts.

What spindle speed prevents tap breakage when threading titanium?

Keep speeds low: M2–M3 at 200–300 rpm and M4–M6 at 300–500 rpm since high speed shortens tap life and snaps the tool inside the hole. BJCJTi's machinists run reduced RPM with peck feeding and frequent retraction protecting tiny M3-and-below taps that are especially brittle.

Which lubricant should be used for titanium thread tapping?

Use plain water standard emulsion or machine oil—never extreme-pressure or sulfur-based cutting oil which aggravate titanium sticking. BJCJTi relies on adequate correct lubrication plus a chamfered entry and coaxial spindle to produce clean gauge-passing small titanium threads without seizing.

How does BJCJTi ensure precision and consistency in titanium thread production?

BJCJTi controls every variable—enlarged pilot holes PM-HSSDLC tooling low RPM correct lubricant chamfer and coaxial setup—then verifies with gono-go gauges at 6H precision. With 15+ years of titanium machining experience and CNCthread-extrusion lines the company delivers consistent miniature TC4 threads for medical and electronics buyers.

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What is the best way to make small threads on titanium alloys?

2026-03-30

I’ll show you exactly how to make small titanium alloy threads (M1–M6) in the most practical way—ready for immediate use on the factory floor. Drawing on hands-on experience from the workshop at Baoji Chengjin Titanium Industry, this guide is straightforward, no-nonsense, and helps you avoid common pitfalls.

What is the best way to make small threads on titanium alloys (1)

What is the best way to make small threads on titanium alloys (2)

How do you make small threads on titanium alloys?

1. First, remember this:

Use a small-threaded titanium alloy drill bit, work slowly, use plenty of lubricant, enlarge the pilot hole, and ensure smooth chip removal—and you’re basically all set.

2. Material Characteristics

High elasticity; tends to spring back after cutting, which can easily jam the tap

Poor heat dissipation; heat accumulates at the cutting edge

Prone to sticking, chipping, and tooth breakage

Small taps (M3 and below) are very brittle and break easily under pressure

3. How to Drill Pilot Holes

The standard pilot hole should be slightly enlarged; otherwise, the thread will be too tight and the tap is likely to break.

M2: Standard pilot hole φ1.6 → φ1.65 for titanium alloy

M3: Standard pilot hole φ2.5 → φ2.55 for titanium alloy

M4: Standard pilot hole φ3.3 → φ3.35 for titanium alloy

M5: Standard pilot hole φ4.2 → φ4.25 for titanium alloy

M6: Standard pilot hole φ5.0 → φ5.1 for titanium alloy

Rule of thumb: 0.05–0.1 mm larger than the standard

What is the best way to make small threads on titanium alloys (3)

What is the best way to make small threads on titanium alloys (4)

4. How to Choose a Tap

Material: Powdered High-Speed Steel (PM-HSS)

Flute Type: Helical flutes for blind holes; straight flutes for through holes

Coating: No TiN! No TiCN! Recommended: Oxide treatment, DLC, ALCRN

V. Spindle Speed (Very Important): Must be slow!

M2–M3: 200–300 rpm

M4–M6: 300–500 rpm

High speed = Short tap life = Tap breaks off inside

5. Tapping Methods

Blind holes: Use the peck-and-drill method, advancing a little and then retracting to clear chips.

Through holes: You can tap continuously, but be sure to retract the tool frequently.

6. Lubrication Must Be Adequate

Without the right oil, you simply can’t make small threads in titanium alloy.

Do not use extreme-pressure tapping oil or sulfur-based cutting oil: use plain water, standard emulsion, or machine oil.

7. Key Operating Points

The hole must be chamfered; otherwise, the tap will chip as soon as it enters.

The spindle must be coaxial with the workpiece and must not wobble.

Do not apply excessive torque, as the titanium alloy may seize up.

After tapping, check with a go/no-go gauge; 6H precision provides the most consistent results.

8. How to Troubleshoot Common Issues

Tapping tool broke: Speed too high, chip buildup, pilot hole too small

Threads stripped: Tool sticking → Change oil, reduce speed

Passed the go gauge: Pilot hole too small → Enlarge it next time

Failed the no-go gauge: Pilot hole too large → Reduce it by 0.05

9. A Simple Summary

Enlarge the pilot hole just a little, reduce the spindle speed by more than half, use plenty of extreme-pressure lubricant, and frequently retract the tool while using a pecking feed method—this will ensure smooth machining of small threads.