{"product_id":"wiseman-hss-bsp-left-hand-split-dies-british-standard-pipe-parallel-lh-thread","title":"Wiseman HSS BSP Left Hand Split Dies – British Standard Pipe Parallel LH Thread","description":"\u003cp data-pm-slice=\"1 3 []\" style=\"text-align: center;\"\u003e\u003cspan\u003eWiseman HSS BSP Left Hand Split Dies are manufactured from High Speed Steel (HSS) and designed for cutting new external BSP (British Standard Pipe) parallel left-hand threads, as well as repairing, cleaning and restoring damaged or worn existing threads.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp style=\"text-align: center;\"\u003e\u003cspan\u003eThese 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 specialist engineering, machinery maintenance, pipe fitting and workshop applications requiring left-hand threaded components.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp style=\"text-align: center;\"\u003e\u003cspan\u003eBSP parallel threads, also known as BSPP or G threads, feature a \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e55° Whitworth thread profile\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e with rounded crests and roots. Unlike BSPT (British Standard Pipe Taper) threads, BSP parallel threads maintain a constant diameter along the threaded section.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp style=\"text-align: center;\"\u003e\u003cspan\u003eUnlike standard right-hand threads, \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eleft-hand BSP threads tighten anticlockwise and loosen clockwise\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e. These reverse-threaded connections are used in specialist equipment and mechanical assemblies where left-hand threads are required by the original design.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp style=\"text-align: center;\"\u003e\u003cspan\u003eBSP parallel threads are commonly used in hydraulic, pneumatic and industrial fittings. Where a pressure-tight connection is required, sealing is normally achieved using a suitable washer, O-ring, gasket or other sealing arrangement rather than the parallel threads themselves.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp style=\"text-align: center;\"\u003e\u003cspan\u003eThese split dies are suitable for producing and restoring left-hand BSP parallel external threads on compatible pipes, fittings, adapters and other threaded components.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2 style=\"text-align: center;\"\u003e\u003cspan\u003eKey Features\u003c\/span\u003e\u003c\/h2\u003e\n\u003cul data-spread=\"false\" style=\"text-align: center;\"\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eHigh Speed Steel (HSS)\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e – Durable construction for reliable thread cutting and maintenance.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eBSP Parallel Thread Form\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e – Designed for British Standard Pipe Parallel external threads.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eLeft Hand Thread\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e – Tightens anticlockwise and loosens clockwise.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eAdjustable Split Design\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e – Allows minor adjustment of the thread fit when used with a suitable die stock.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eRound Die Construction\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e – Designed for use with compatible die stocks and die holders.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003e55° Whitworth Thread Profile\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e – Features rounded crests and roots.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eParallel Thread Design\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e – Produces threads with a constant nominal major diameter along their length.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eThread Cutting \u0026amp; Restoration\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e – Suitable for cutting new external threads and repairing existing threads.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eSpecialist Engineering Applications\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e – Suitable for equipment requiring left-hand BSP parallel threads.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2 style=\"text-align: center;\"\u003e\u003cspan\u003eApplications\u003c\/span\u003e\u003c\/h2\u003e\n\u003cp style=\"text-align: center;\"\u003e\u003cspan\u003eSuitable for:\u003c\/span\u003e\u003c\/p\u003e\n\u003cul data-spread=\"false\" style=\"text-align: center;\"\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cspan\u003eCutting new BSP parallel left-hand external threads.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cspan\u003eRepairing damaged or worn BSP left-hand threads.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cspan\u003eCleaning and restoring existing external threads.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cspan\u003eManufacturing specialist left-hand threaded pipe fittings.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cspan\u003eHydraulic fittings and adapters requiring BSP LH threads.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cspan\u003ePneumatic equipment and industrial machinery.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cspan\u003eMechanical assemblies requiring reverse-threaded connections.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cspan\u003eGeneral engineering and workshop machining.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cspan\u003eManufacturing replacement left-hand threaded components.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2 style=\"text-align: center;\"\u003e\u003cspan\u003eRecommended Use\u003c\/span\u003e\u003c\/h2\u003e\n\u003cp style=\"text-align: center;\"\u003e\u003cspan\u003eSelect the correct BSP left-hand split die size and threads per inch (TPI) to match the required external thread.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp style=\"text-align: center;\"\u003e\u003cspan\u003eBSP sizes are designated by nominal pipe sizes rather than the actual outside diameter of the thread. For example, a 1\/2\" BSP thread has an external major diameter of approximately 20.96mm, not 12.7mm.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp style=\"text-align: center;\"\u003e\u003cspan\u003eSecure 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.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp style=\"text-align: center;\"\u003e\u003cspan\u003eApply a suitable cutting lubricant and rotate the die \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eanticlockwise to cut the left-hand thread\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, viewed from the starting end of the workpiece. Periodically reverse the die clockwise slightly to help break and clear chips where appropriate for the material and cutting conditions.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp style=\"text-align: center;\"\u003e\u003cspan\u003eThe adjustable split design allows minor adjustments to the thread fit. Check the finished thread using a suitable BSP parallel left-hand thread gauge or correctly specified mating component.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp style=\"text-align: center;\"\u003e\u003cspan\u003eWhere the threaded connection is required to seal against pressure, ensure that the appropriate sealing method is used and that the complete connection is suitable for the intended application.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2 style=\"text-align: center;\"\u003e\u003cspan\u003eImportant\u003c\/span\u003e\u003c\/h2\u003e\n\u003cul data-spread=\"false\"\u003e\n\u003cli style=\"text-align: center;\"\u003e\n\u003cp\u003e\u003cspan\u003eSuitable for \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eBSP (British Standard Pipe Parallel) left-hand external threads only\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli style=\"text-align: center;\"\u003e\n\u003cp\u003e\u003cspan\u003eLeft-hand threads tighten anticlockwise and loosen clockwise.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli style=\"text-align: center;\"\u003e\n\u003cp\u003e\u003cspan\u003eNot suitable for cutting standard right-hand BSP threads.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli style=\"text-align: center;\"\u003e\n\u003cp\u003e\u003cspan\u003eFeatures a 55° Whitworth thread profile.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli style=\"text-align: center;\"\u003e\n\u003cp\u003e\u003cspan\u003eProduces parallel threads, not tapered threads.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli style=\"text-align: center;\"\u003e\n\u003cp\u003e\u003cspan\u003eNot interchangeable with BSPT or NPT dies.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli style=\"text-align: center;\"\u003e\n\u003cp\u003e\u003cspan\u003eBSP nominal thread sizes do not correspond directly to the measured external thread diameter.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli style=\"text-align: center;\"\u003e\n\u003cp\u003e\u003cspan\u003eBSP parallel threads generally require a separate sealing arrangement where a pressure-tight connection is needed.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli style=\"text-align: center;\"\u003e\n\u003cp\u003e\u003cspan\u003eAdjustable round split die for cutting and restoring external threads.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp style=\"text-align: center;\"\u003e\u003cspan\u003eRequires a compatible die stock or die holder.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Rennie Tool Company","offers":[{"title":"1\/8\" x 28 BSP Left Hand (1\" OD)","offer_id":57740561613175,"sku":"D50551L","price":79.19,"currency_code":"GBP","in_stock":true},{"title":"1\/4\" x 19 BSP Left Hand (1.5\/16\" OD)","offer_id":57740561645943,"sku":"D50602L","price":87.86,"currency_code":"GBP","in_stock":true},{"title":"3\/8\" x 19 BSP Left Hand (1.1\/2\" OD)","offer_id":57740561678711,"sku":"D50653L","price":121.39,"currency_code":"GBP","in_stock":true},{"title":"1\/2\" x 14 BSP Left Hand (1.1\/2\" OD)","offer_id":57740561711479,"sku":"D50703L","price":121.39,"currency_code":"GBP","in_stock":true},{"title":"5\/8\" x 14 BSP Left Hand (2\" OD)","offer_id":57740561744247,"sku":"D50755L","price":145.45,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0067\/9129\/9145\/files\/WisemanSplitDie_1e3d6cb7-6db1-4e70-a26f-cc79305d4ad6.png?v=1788643504","url":"https:\/\/www.rennietool.co.uk\/products\/wiseman-hss-bsp-left-hand-split-dies-british-standard-pipe-parallel-lh-thread","provider":"Rennie Tool Company","version":"1.0","type":"link"}