{"product_id":"iscar-4503112-retention-knob-cat50-1-8-thread-through-coolant","title":"Iscar 4503112 Retention Knob CAT50 1-8 Thread Through Coolant","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\u003cp\u003eThe ISCAR 4503112 is a CAT50 retention knob designed for securing tool holders in CAT50 spindle tapers on CNC machining centers. It features a 1-8 inch thread, a 45-degree angle radius, and a knob diameter of 0.906 inches with an overall length of 3.346 inches. The through-coolant design includes a 0.236-inch coolant hole diameter, enabling direct coolant delivery to the cutting zone. Machining centers in production and job-shop environments rely on properly torqued retention knobs like this one to maintain drawbar pull force and prevent tool pull-out under heavy cutting loads. This part weighs 1 pound.\u003c\/p\u003e\u003cp\u003eThis retention knob is suited for CNC vertical and horizontal machining centers equipped with CAT50 spindle tooling systems. It is a direct replacement component used during tool holder maintenance or when an existing retention knob shows wear, thread damage, or fails drawbar pull testing. The through-coolant passage supports flood or high-pressure coolant strategies common in ferrous and non-ferrous machining applications. Installation is performed by tool crib technicians or machine operators during standard tool holder assembly.\u003c\/p\u003e\u003ch4\u003eKey Features\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003eCAT50 taper size for use in CAT50 spindle machining systems\u003c\/li\u003e\n\u003cli\u003e1-8 inch thread specification for compatibility with standard CAT50 drawbars\u003c\/li\u003e\n\u003cli\u003e45-degree angle radius for proper seating against the drawbar contact surface\u003c\/li\u003e\n\u003cli\u003eThrough-coolant capable with a 0.236-inch coolant hole diameter\u003c\/li\u003e\n\u003cli\u003eKnob to flange length of 1.772 inches and neck diameter of 0.670 inches\u003c\/li\u003e\n\u003cli\u003eOverall length of 3.346 inches for standard CAT50 tool holder fitment\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eCompatibility\u003c\/h4\u003e\u003cp\u003eDesigned as an OEM-style replacement retention knob for CAT50 taper tool holders using a 1-8 inch drawbar thread.\u003c\/p\u003e\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\u003cp\u003eRetention knobs are installed by tool crib personnel or qualified machine operators using a retention knob wrench and a torque wrench calibrated to the tool holder manufacturer's specification. Always power down and lock out the machining center spindle before servicing tool holders or retention knobs. Do not over-torque the retention knob, as excess torque can deform the tool holder taper and reduce spindle contact accuracy. Inspect the drawbar and spindle bore for debris or damage before reinstalling.\u003c\/p\u003e\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eTaper Size\u003c\/strong\u003e: CAT50\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread Size\u003c\/strong\u003e: 1-8 inch\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAngle Radius\u003c\/strong\u003e: 45 degrees\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eKnob Diameter\u003c\/strong\u003e: 0.906 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNeck Diameter\u003c\/strong\u003e: 0.670 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eKnob to Flange Length\u003c\/strong\u003e: 1.772 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOverall Length\u003c\/strong\u003e: 3.346 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCoolant Hole Diameter\u003c\/strong\u003e: 0.236 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThrough Coolant\u003c\/strong\u003e: Yes\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight\u003c\/strong\u003e: 1 pound\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePackage Quantity\u003c\/strong\u003e: 1\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eStandard Information\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand\u003c\/strong\u003e: ISCAR\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: 4503112\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"ISCAR","offers":[{"title":"Default Title","offer_id":51749559042354,"sku":"4503112","price":62.12,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/f7da55e7a80d0e865dc9cb640c91a588_9c3fee4e-d074-496a-931c-bbd6b70fe6b2.jpg?v=1788907608","url":"https:\/\/voomisupply.com\/products\/iscar-4503112-retention-knob-cat50-1-8-thread-through-coolant","provider":"Voomi Supply","version":"1.0","type":"link"}