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Baer Heli Coil Tap - Wire Thread Insert - Bottoming Tap (STI) - UNF - 9/16 x 18
| Thread Form | UNF |
| Size | 9/16 |
| Pitch | 18 |
| Lead | Bottoming Tap (STI) |
| Thread Direction | Right Hand |
| Tolerance | 3B |
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Baer Heli Coil Tap - Wire Thread Insert - Bottoming Tap (STI) - UNF - 9/16 x 18 is a precision cutting tool designed to create robust, repair-ready internal threads for Helicoil wire thread inserts. Built to deliver consistent results, this bottoming tap cuts cleanly to full depth, ensuring a reliable foundation for high-load fasteners and critical assemblies.
Designed for UNF threads and a 9/16 x 18 size, this tap excels in automotive, manufacturing, and maintenance projects where damaged or stripped threads threaten performance. The bottoming geometry reaches the very bottom of the hole, producing complete threads from the first cut to the final turn. That means stronger inserts, improved load distribution, and fewer insert failures in tough operating environments.
Key benefits and how they matter:
- Full-depth threading — The bottoming design engages every thread from top to bottom, ensuring the Helicoil insert seats properly and delivers the maximum holding power.
- Reliable thread reinforcement — Ideal for repairing damaged threads or reinforcing soft metals where standard taps would leave weak, shallow threads.
- STI-driven performance — Engineered to pair seamlessly with Helicoil wire thread inserts, providing a dependable path to durable, repairable threads in a variety of materials.
- Versatile UNF compatibility — Optimized for UNF threads, specifically 9/16 x 18, making it a go-to choice for modern fastener schemes in automotive, machinery, and equipment maintenance.
- Professional-grade durability — Built to withstand repeated use in workshop settings, delivering consistent results you can trust on every project.
Practical use scenarios:
- Repairting stripped or damaged holes in engine blocks, cylinder heads, or mounting flanges where strong, repeatable threads are essential.
- Reinforcing aluminum housings, transmission cases, or brackets that experience frequent load cycling and vibration.
- Preparing holes for Helicoil inserts in repair-then-reuse applications, ensuring a secure grip for bolts and studs.
Tips for best results:
- Use proper cutting fluid or light oil to reduce friction and extend tap life during cutting.
- Align the tap square to the workpiece to avoid cross-threading and ensure true thread formation.
- Clean chips frequently; a clogged thread can compromise insert seating and performance.
- Pair with the corresponding Helicoil insert tooling to streamline installation and achieve a clean, secure reinforcement.
Whether you’re a shop tech tackling routine maintenance or a professional fabricator restoring critical components, the Baer Heli Coil Tap - UNF 9/16 x 18 Bottoming Tap is built to deliver durable, accurate internal threads that stand up to demanding applications. It’s more than a tap—it’s a reliable pathway to lasting thread integrity and gear-ready performance.
| Thread Form | UNF |
| Size | 9/16 |
| Pitch | 18 |
| Lead | Bottoming Tap (STI) |
| Thread Direction | Right Hand |
| Tolerance | 3B |
| Tap Diameter (D1) | 16.1 |
| Flute Length (L2) | 29 |
| Overall Length (L1) | 104 |
| Shank Diameter (D2) | 12.5 |
| Square Drive | 10 |
What time are Protool open?
We are open Monday to Friday between 8:30am and 5pm.
Do you offer Free Next Day delivery?
Yes! We offer Free Next Day delivery via Royal Mail Tracked 24 on all orders over £50 ex VAT*. We also offer Free DPD Local Next Day delivery on all orders over £100 ex VAT*.
We also offer the following:
- Royal Mail Tracked 24 — £5.90 (FREE on orders over £50 ex VAT*). Order before 4:30pm for next day delivery. No signature required.
- DPD Local Next Day — £8.00 (FREE on orders over £100 ex VAT*). Standard next day delivery to UK mainland addresses.
- Royal Mail Special Delivery — £12.50. Guaranteed delivery before 1pm the next working day.
- DPD Saturday Delivery — £25.00. Must be ordered on Friday before 4pm. Pre-12pm delivery.
For delivery to Scottish Highlands & Islands, Northern Ireland, Republic of Ireland, or overseas locations, additional charges apply. Please see our delivery page for full details, or call us on 01732 887 334.
*T's & C's and exclusions apply. Please see our delivery page for more information on all our services.
Full Range: Baer Heli Coil Taps - Wire Thread Insert - Bottoming Tap (STI) - UNF
View full collection →You are viewing BAER-B3160. Click any other SKU to view its full details.
| Product SKU | Size | Pitch | Tap Diameter (D1) | Flute Length (L2) | Overall Length (L1) | Shank Diameter (D2) | Price | Stock | Order |
|---|---|---|---|---|---|---|---|---|---|
| BAER-B3151 | No. 4 | 48 | 3.5 | 13 | 53 | 4 | £14.86 | 5 days | |
| BAER-B3152 | No. 6 | 40 | 4.3 | 13 | 53 | 4.5 | £14.86 | 5 days | |
| BAER-B3153 | No. 8 | 36 | 5.1 | 17 | 62 | 5.6 | £14.86 | 5 days | |
| BAER-B3154 | No. 10 | 32 | 5.9 | 19 | 66 | 6.3 | £14.86 | 5 days | |
| BAER-B3155 | 1/4 | 28 | 7.5 | 19 | 69 | 8 | £9.77 | 5 days | |
| BAER-B3156 | 5/16 | 24 | 9.3 | 20 | 76 | 10 | £10.84 | 5 days | |
| BAER-B3157 | 3/8 | 24 | 10.9 | 22 | 82 | 8 | £11.13 | 5 days | |
| BAER-B3158 | 7/16 | 20 | 12.8 | 24 | 84 | 9 | £14.86 | 5 days | |
| BAER-B3159 | 1/2 | 20 | 14.4 | 25 | 90 | 11.2 | £16.89 | 5 days | |
| BAER-B3160 Viewing | 9/16 | 18 | 16.1 | 29 | 104 | 12.5 | £28.50 | 5 days | |
| BAER-B3161 | 5/8 | 18 | 17.7 | 29 | 104 | 14 | £35.14 | 5 days | |
| BAER-B3162 | 3/4 | 16 | 21.1 | 29 | 104 | 14 | £43.03 | 5 days | |
| BAER-B3163 | 7/8 | 14 | 24.6 | 35 | 120 | 18 | £62.05 | 5 days | |
| BAER-B3164 | 1 | 12 | 28.2 | 37 | 127 | 20 | £62.05 | 5 days | |
| BAER-B3165 | 1 | 14 | 27.8 | 37 | 127 | 20 | £62.90 | 5 days |
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