{"product_id":"knightsbridge-51mm-bi-metal-holesaw-yellow","title":"Knightsbridge 51mm Bi-Metal Holesaw - Yellow","description":"\u003ch5\u003eDescription\u003c\/h5\u003e\n\u003cp\u003eThe Knightsbridge 51mm bi-metal holesaw features a 51mm overall diameter cutting edge with 4\/6 TPI (teeth per inch) variable tooth geometry, designed to cut through steel, stainless steel, die-cast metals, hardwood floors, plywood and plastics. The bi-metal construction combines a high-speed steel cutting edge with a spring steel body, giving the saw resistance to heat and tooth stripping when cutting harder materials.\u003c\/p\u003e\n\u003cp\u003eDesigned for electrical installation work where a 51mm diameter hole is required for downlights, ceiling speakers, or cable pass-throughs, the holesaw provides a 38mm maximum cutting depth and fits standard arbors (sold separately, use Knightsbridge HSARBORL arbor). The variable tooth pitch reduces vibration during cutting and improves chip clearance compared to fixed-pitch designs, which matters when drilling through layered materials like plasterboard-backed steel stud.\u003c\/p\u003e\n\u003cp\u003eThe bright yellow finish on the steel body makes the holesaw easy to locate in a toolbox or on a site floor. The bi-metal edge retains sharpness through multiple cuts in soft and medium-hardness materials, though cutting depth and lifespan reduce when used on stainless steel or hardened metals compared to softwood or plywood.\u003c\/p\u003e\n\u003ch5\u003eSpecification\u003c\/h5\u003e\n\u003ctable class=\"spec_table\"\u003e\n\u003ctr\u003e\n\u003ctd\u003eDiameter\u003c\/td\u003e\n\u003ctd\u003e51 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRecessed Depth\u003c\/td\u003e\n\u003ctd\u003e38 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCut-out Diameter\u003c\/td\u003e\n\u003ctd\u003e51 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eConstruction\u003c\/td\u003e\n\u003ctd\u003eSteel\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFinish\u003c\/td\u003e\n\u003ctd\u003eYellow\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWarranty\u003c\/td\u003e\n\u003ctd\u003e0\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\u003ch5\u003eDownloads\u003c\/h5\u003e\n\u003cp\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0729\/8993\/3835\/files\/products_1541329_datasheet.pdf\" target=\"_blank\"\u003eProduct Specification Sheet\u003c\/a\u003e\u003c\/p\u003e\n\u003ch5\u003eFrequently Asked\u003c\/h5\u003e\n\u003cp\u003e\u003cstrong\u003eWhat arbor does this holesaw require?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe 51mm holesaw fits the Knightsbridge HSARBORL arbor, sold separately. The arbor provides the mandrel and pilot drill bit needed to centre and drive the holesaw during cutting.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat materials can it cut?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe bi-metal construction handles steel, stainless steel, die-cast metals, hardwood floors, plywood and plastics. Cutting depth and blade life are longest in softwood and plywood, and reduce when cutting stainless steel or hardened metals.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat's the maximum cutting depth?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe holesaw cuts to a maximum depth of 38mm in a single pass. For materials thicker than 38mm, the hole must be cut from both sides or the saw withdrawn and repositioned.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat does 4\/6 TPI variable teeth mean?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eTPI (teeth per inch) refers to tooth density. Variable pitch means the spacing between teeth alternates between 4 TPI and 6 TPI sections along the cutting edge, which reduces vibration and improves chip clearance when drilling layered or mixed materials.\u003c\/p\u003e","brand":"Knightsbridge","offers":[{"title":"Default Title","offer_id":45293885849867,"sku":"HS51MM","price":5.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0729\/8993\/3835\/files\/1428950_00213632-5941-4d26-918f-b9b4059b9e62.jpg?v=1714665539","url":"https:\/\/niori.co.uk\/products\/knightsbridge-51mm-bi-metal-holesaw-yellow","provider":"Niori","version":"1.0","type":"link"}