VÖLKEL Thread Repair Workshop Kit BSF 1/4 – BSF 1/2

Use this workshop kit for repeated V-COIL repairs across the stated size range when a damaged internal thread must be rebuilt rather than only cleaned. The decisive selection points are repair size BSF 1/4, insert length where stated, and the tools included in the kit.

VÖLKEL Thread Repair Workshop Kit BSF 1/4 – BSF 1/2

Features and applications

Use this workshop kit for repeated V-COIL repairs across the stated size range when a damaged internal thread must be rebuilt rather than only cleaned. The decisive selection points are repair size BSF 1/4, insert length where stated, and the tools included in the kit.

BSF identifies a British Standard Fine thread used where a finer Whitworth thread series is specified. The kit should be selected by the component thread, available wall thickness, and the required installation workflow. Check the thread designation, tool stage, holder guidance, lubrication, and inspection method before work starts.

Applications

• repairing damaged internal BSF 1/4 threads with the V-COIL repair process
• workshop and maintenance repairs where the original screw size should remain usable
• component repair in housings, covers, brackets, flanges, and similar metal parts
• selection by thread size, insert length, included tools, and required inspection method

Benefits

• kit structure keeps the repair workflow connected to BSF 1/4
• coordinated preparation, STI tapping, insertion, and checking steps reduce the risk of mixing tools from different sizes
• insert repair can retain the original screw size when the component condition allows controlled preparation

Application limits

• A repair kit only works when the damaged component can be prepared correctly; replace the component or use a different repair method if alignment or remaining wall strength is not sufficient.

Step by step

1. Identify the damaged thread and confirm that the kit is the correct repair size for BSF 1/4.
2. Secure the component so the preparation tool can follow the original thread axis.
3. Prepare the damaged hole with the drilling or cleaning step required by the kit workflow.
4. Cut the STI receiving thread with the included or specified repair tap.
5. Clean the hole and remove chips before the insert is installed.
6. Install the wire thread insert with the correct inserting tool until the seating position is reached.
7. Remove the tang where the selected insert system requires that step.
8. Check the repaired thread with the mating screw or inspection method used in your process.

Used together with

Each component in the kit has its own VÖLKEL item number for reordering.

• STI Short Machine Tap ISO 529 Form D HSS-G - BSF 1/4 x 26: item 03253
• STI Short Machine Tap ISO 529 Form D HSS-G - BSF 5/16 x 22: item 03255
• STI Short Machine Tap ISO 529 Form D HSS-G - BSF 3/8 x 20: item 03256
• STI Short Machine Tap ISO 529 Form D HSS-G - BSF 7/16 x 18: item 03257
• STI Short Machine Tap ISO 529 Form D HSS-G - BSF 1/2 x 16: item 03258
• STI-Twist Drill, 6.6 mm: item 00066
• STI-Twist Drill, 8.3 mm: item 00083
• STI-Twist Drill, 9.9 mm: item 00099
• STI-Twist Drill, 11.5 mm: item 00115
• STI-Twist Drill, 13.0 mm: item 00130
• V-COIL Inserting Tool No. 9: item 08009
• V-COIL Inserting Tool No. 11: item 08011
• V-COIL Inserting Tool No. 12: item 08012
• V-COIL Inserting Tool No. 14: item 08014
• V-COIL Inserting Tool No. 15: item 08015
• Tang Break Tool No. 9: item 07009
• Tang Break Tool No. 11: item 07011
• Tang Break Tool No. 12: item 07012
• Tang Break Tool No. 14: item 07014
• Tang Break Tool No. 15: item 07015
• V-COIL Wire thread insert Free running type S BSF 1/4 x 26 - 1.5 D: item 08363
• V-COIL Wire thread insert Free running type S BSF 5/16 x 22 - 1.5 D: item 08365
• V-COIL Wire thread insert Free running type S BSF 3/8 x 20 - 1.5 D: item 08366
• V-COIL Wire thread insert Free running type S BSF 7/16 x 18 - 1.5 D: item 08367
• V-COIL Wire thread insert Free running type S BSF 1/2 x 16 - 1.5 D: item 08368

How to choose

Confirm BSF 1/4, the insert length, and every included tool before starting the repair.