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VCOIL Plug Gauge (NoGo) - UNF (STI) - Heli Coil Gauge - Right Hand - 3B - 1.3/8 x 12
| Thread Form | UNF (STI) |
| Size | 1.3/8 |
| Pitch | 12 |
| Gauge Type | Plug Gauge (NoGo) |
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The ones our customers buy most.Description
Introducing the VCOIL Plug Gauge NoGo for UNF (STI) – a precise, combined go/no-go gauge designed for Helicoil insert applications. Built for right-hand UNF threads at 1-3/8 x 12 with a 3B tolerance, it helps shops verify thread quality quickly and consistently.
- Combined Go/No-Go design: A single gauge that tests both the go condition (hand-screws into the thread) and the no-go condition (scrap side limits how far it can be turned).
- UNF (STI) thread form: Specifically calibrated for right-hand UNF threads, 1-3/8 x 12, with a 3B class tolerance to match Helicoil insert specifications.
- ANSI/ASME compliant: Manufactured and assessed according to relevant ANSI/ASME threading standards for reliable, repeatable measurements.
- Scrap marking with red ring: The scrap side is clearly identified by a red ring to prevent misreads during inspection.
- Right-hand orientation: Optimized for right-hand threads to support standard machining and assembly workflows.
- 20°C reference temperature: Measurements reference at 20°C to ensure consistency across parts and gauges in production environments.
This plug gauge supports efficient quality control by quickly confirming thread adherence and preventing misfits in Helicoil installations. Its knurled exterior and precision threading provide reliable handling and longevity, making it a dependable choice for manufacturing, assembly, and maintenance operations that rely on precise UNF threads.
Part Numbers
- Protool Part Number
- TC-19941
- Brand
- VCOIL
- Category
- Gauge
Need cutting data? Call 01732 887334 or email sales@protool-ltd.co.uk.
Delivery
Free UK mainland delivery on orders over £50 ex VAT. In-stock items ordered before 4:30pm are dispatched the same working day. Full delivery information.
Returns
14-day returns on unused stock items in original packaging. Special-order and bespoke tooling is non-returnable. Read our returns policy.
Technical Support
Over 30 years of machining experience behind the counter. Call 01732 887334, Mon–Thurs 8:30–17:30, Fri 8:30–16:30.
Trade Accounts
Credit accounts, contract pricing and scheduled call-off orders available for trade customers. Apply for an account.
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: VCOIL Plug Gauges UNF (STI)
View full collection →You are viewing TC-19941. Click any other SKU to view its full details.
| Product SKU | Size | Pitch | Price | Stock | Order |
|---|---|---|---|---|---|
| TC-19823 | No. 4 | 48 | £102.03 | In Stock | |
| TC-19824 | No. 6 | 40 | £102.03 | In Stock | |
| TC-19825 | No. 8 | 36 | £98.05 | In Stock | |
| TC-19826 | No. 10 | 32 | £98.05 | 7 days | |
| TC-19827 | 1/4 | 28 | £95.40 | 7 days | |
| TC-19828 | 5/16 | 24 | £99.38 | 7 days | |
| TC-19829 | 3/8 | 24 | £103.35 | 7 days | |
| TC-19830 | 7/16 | 20 | £108.65 | In Stock | |
| TC-19831 | 1/2 | 20 | £113.95 | 7 days | |
| TC-19832 | 9/16 | 18 | £123.23 | In Stock | |
| TC-19833 | 5/8 | 18 | £137.80 | In Stock | |
| TC-19834 | 3/4 | 16 | £169.60 | 7 days | |
| TC-19835 | 7/8 | 14 | £184.18 | 7 days | |
| TC-19836 | 1 | 12 | £221.28 | 7 days | |
| TC-19837 | 1 | 14 | £221.28 | 7 days | |
| TC-19838 | 1.1/8 | 12 | £221.28 | 7 days | |
| TC-19839 | 1.1/4 | 12 | £257.05 | 7 days | |
| TC-19840 | 1.3/8 | 12 | £166.95 | 7 days | |
| TC-19841 | 1.3/8 | 12 | £166.95 | 7 days | |
| TC-19842 | 1.1/2 | 12 | £194.78 | 7 days | |
| TC-19843 | 1.1/2 | 12 | £194.78 | 7 days | |
| TC-19923 | No. 4 | 48 | £121.90 | 7 days | |
| TC-19924 | No. 6 | 40 | £121.90 | 7 days | |
| TC-19925 | No. 8 | 36 | £116.60 | 7 days | |
| TC-19926 | No. 10 | 32 | £116.60 | 7 days | |
| TC-19927 | 1/4 | 28 | £115.28 | 7 days | |
| TC-19928 | 5/16 | 24 | £119.25 | 7 days | |
| TC-19929 | 3/8 | 24 | £123.23 | 7 days | |
| TC-19930 | 7/16 | 20 | £129.85 | 7 days | |
| TC-19931 | 1/2 | 20 | £136.48 | 7 days | |
| TC-19932 | 9/16 | 18 | £148.40 | 7 days | |
| TC-19933 | 5/8 | 18 | £165.63 | 7 days | |
| TC-19934 | 3/4 | 16 | £202.73 | 7 days | |
| TC-19935 | 7/8 | 14 | £221.28 | 7 days | |
| TC-19936 | 1 | 12 | £265.00 | 7 days | |
| TC-19937 | 1 | 14 | £265.00 | 7 days | |
| TC-19938 | 1.1/8 | 12 | £265.00 | 7 days | |
| TC-19939 | 1.1/4 | 12 | £308.73 | 7 days | |
| TC-19940 | 1.3/8 | 12 | £201.40 | 7 days | |
| TC-19941 Viewing | 1.3/8 | 12 | £201.40 | 7 days | |
| TC-19942 | 1.1/2 | 12 | £234.53 | 7 days | |
| TC-19943 | 1.1/2 | 12 | £234.53 | 7 days |
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