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Baer Heli Coil Tap - Wire Thread Insert - Bottoming Tap (STI) - UNF - 7/8 x 14
| Thread Form | UNF |
| Size | 7/8 |
| Pitch | 14 |
| 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 - 7/8 x 14
When threaded holes take a beating, this Heli Coil Tap is your go-to tool for restoring strength and reliability. Specifically engineered to work with Heli-Coil wire thread inserts, it delivers clean, precise internal threads that stand up to the demands of repeated assembly and disassembly in challenging environments. The result is renewed hole integrity and a repair you can trust in critical applications.
Why this tap stands out
- Bottoming precision for blind holes — the bottoming geometry reaches the full thread depth, ensuring the insert sits properly and engages fully from top to bottom.
- UNF compatibility — designed for 7/8 x 14 unified National Fine threads, so you can confidently repair or reinforce holes that require a fine-pitched standard.
- Designed for durable repairs — engineered to produce strong, long-lasting threads that resist pull-out and wear, even in high-stress environments.
- Optimized for Heli-Coil inserts — precisely paired with coil inserts to restore original thread strength and torque capacity without compromising hole geometry.
- Built for repeated use — constructed to withstand routine tapping in a variety of materials, making it a dependable choice for shops and workbenches alike.
Ideal applications
Perfect for automotive, industrial, and workshop repairs where threaded holes have become weakened or damaged. Use it to:
- Rebuild stripped or worn UNF 7/8-14 threads in automotive blocks, engine components, and transmission housings.
- Repair threaded receptacles in machinery housings, brackets, and equipment mounts that require reliable load-bearing threads.
- Prepare clean, accurate internal threads for Heli-Coil inserts, restoring original strength and service life.
How it helps your workflow
With the Baer Heli Coil Tap, you gain predictable results time after time. The tap’s geometry creates consistent thread profiles, reducing the risk of cross-threading and ensuring the insert seats smoothly. That means faster repairs, fewer follow-up adjustments, and a durable repair you can rely on in the field or the shop.
Key specifications at a glance
- Thread type: UNF
- Size: 7/8 x 14
- Design: Bottoming tap (STI) for full-depth threads
- Application: Preparation for Heli-Coil wire thread inserts
Practical tips for best results
- Use proper tapping fluid to reduce friction and extend tool life.
- Keep the hole aligned to prevent thread distortion; slow, steady strokes help maintain accuracy.
- Clean the hole thoroughly after tapping to remove chips before installing the coil insert.
- Follow insert manufacturer guidelines for seating depth and torque limits to maximize strength.
Maintenance and care
After use, wipe the tap clean to remove metal shavings and inspect for any burrs or wear. Store in a dry, organized case to preserve edge sharpness and prevent corrosion. Regular inspection and careful use will extend the life of this essential repair tool.
Upgrade your repair toolkit with the Baer Heli Coil Tap and deliver durable, reliable thread repairs that stand up to real-world use. Whether you’re a professional machinist, a maintenance technician, or a serious hobbyist, this bottoming tap is built to help you reclaim threaded holes and keep equipment functioning at peak performance.
| Thread Form | UNF |
| Size | 7/8 |
| Pitch | 14 |
| Lead | Bottoming Tap (STI) |
| Thread Direction | Right Hand |
| Tolerance | 3B |
| Tap Diameter (D1) | 24.6 |
| Flute Length (L2) | 35 |
| Overall Length (L1) | 120 |
| Shank Diameter (D2) | 18 |
| Square Drive | 14 |
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-B3163. 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 | 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 Viewing | 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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