Wiseman HSS WHIT (ME) Split Dies – Model Engineer Whitworth Right Hand Thread

Wiseman HSS WHIT (ME) Split Dies are manufactured from High Speed Steel (HSS) and designed for cutting new external Model Engineer (ME) threads, as well as repairing, cleaning and restoring damaged or worn existing threads.

These round split dies feature an adjustable design, allowing minor adjustments to the thread fit when used with a suitable die stock. They are particularly useful for model engineering, precision machining, miniature mechanical assemblies and restoration applications.

Model Engineer Whitworth threads feature a 55° Whitworth thread profile with rounded crests and roots. The ME thread series commonly uses fine pitches of 32 or 40 threads per inch (TPI), depending on the specified size and application.

These fine-pitch threads are traditionally used in model steam engines, miniature locomotives, model boilers, small mechanical assemblies and specialist engineering projects where relatively fine threads are required on smaller components.

Designed for right-hand thread cutting, these split dies are suitable for producing and restoring Model Engineer Whitworth threads on rods, studs, fittings and other externally threaded components.

Key Features

• High Speed Steel (HSS) – Durable construction for reliable thread cutting and maintenance.

• Model Engineer (ME) Thread Form – Designed for Model Engineer Whitworth external threads.

• Right Hand Thread – Standard clockwise tightening thread direction.

• Adjustable Split Design – Allows minor adjustment of the thread fit when used with a suitable die stock.

• Round Die Construction – Designed for use with compatible die stocks and die holders.

• 55° Whitworth Thread Profile – Features rounded crests and roots.

• Fine Thread Pitches – Commonly available in 32 TPI and 40 TPI configurations.

• Thread Cutting & Restoration – Suitable for producing new external threads and restoring existing threads.

• Model Engineering Applications – Particularly useful for miniature machinery and precision components.

Applications

Suitable for:

• Cutting new Model Engineer Whitworth external threads.

• Repairing damaged or worn ME threads.

• Cleaning and restoring existing external threads.

• Model steam engine construction and maintenance.

• Miniature locomotive and railway model engineering.

• Model boiler fittings, where the thread specification and applicable safety requirements permit.

• Precision engineering and small mechanical assemblies.

• Manufacturing miniature threaded rods, studs and fittings.

• Restoration of vintage model engineering equipment.

Recommended Use

Select the correct Model Engineer Whitworth split die diameter and thread pitch. ME threads are commonly specified in 32 TPI or 40 TPI, and the exact pitch must match the intended component.

Secure the die in a compatible die stock or holder, ensuring the adjustment screws are correctly positioned. Prepare the workpiece to the appropriate diameter and apply a suitable chamfer to help the die start squarely.

Apply a suitable cutting lubricant and rotate the die clockwise to cut the thread. Periodically reverse the die slightly to break and clear chips where appropriate for the material and cutting conditions.

The adjustable split design allows minor adjustments to the thread fit. Check the finished thread using a suitable thread gauge or correctly specified mating component.

Extra care should be taken when cutting fine threads on small-diameter components to avoid excessive cutting pressure or damage to the workpiece.

Important

• Suitable for Model Engineer Whitworth (ME) right-hand external threads.

• Features a 55° Whitworth thread profile.

• Common ME thread pitches include 32 TPI and 40 TPI.

• Not interchangeable with BSW, BSF, BSB, BSP, metric or Unified threads unless the complete thread specification matches.

• Adjustable round split die for cutting and restoring external threads.

• Requires a compatible die stock or die holder.

• Select the correct nominal diameter and TPI before use.

• Thread Reference: Model Engineer Whitworth (ME) thread series.