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VCOIL Plug Gauge (D/E) - UNF (STI) - Heli Coil Gauge - Right Hand - 3B - 1/2 x 20
| Thread Form | UNF (STI) |
| Size | 1/2 |
| Pitch | 20 |
| Gauge Type | Plug Gauge (D/E) |
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The ones our customers buy most.Description
The VCOIL Plug Gauge (D/E) UNF (STI) - Heli Coil Gauge, Right Hand, 3B, 1/2 x 20, is a precision go/no-go thread gauge built to support Helicoil installations and UNF threading checks. Designed for machinists and quality inspectors, it provides reliable, on-tool verification against ANSI/ASME thread standards.
- Thread Type: UNF (Unified National Fine) with a 1/2 x 20 size.
- Go/No-Go Design: Combines a go plug gauge (hand-screws into the thread) and a no-go gauge (scrap side) for clear pass/fail results.
- Scrap Marking: Scrap side is marked with a red ring for quick identification.
- Hand Orientation: Right Hand configuration for standard inspection procedures.
- Class: 3B accuracy class.
- Standards: Manufactured and assessed in accordance with ANSI/ASME thread standards.
- Application: Specifically used for Helicoil gauge inspections of UNF threads.
- Reference Temperature: 20°C reference for parts and gauges to ensure consistent measurements.
With its knurled body and clearly marked ends, this gauge provides confident handling and quick, at-a-glance evaluation during setup, inspection, or quality control. The go end should thread into the part by hand without excessive force, while the scrap side must not thread in more than two complete turns, ensuring any out-of-tolerance threads are promptly identified. This ensures Helicoil inserts meet required specifications, helping reduce rejects and maintain consistent thread quality across production runs.
Part Numbers
- Protool Part Number
- TC-19931
- 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-19931. 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 Viewing | 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 | 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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