{"product_id":"xl12t-timing-pulley-10mm-belt-af-synchronous-wheel","title":"XL12T Synchronous Wheel 4\/5\/6\/6.35\/8mm Bore AF Timing Pulley 10mm Belt Width","description":"\u003cdiv class=\"hdiy-desc\"\u003e\n\u003cdiv class=\"hdiy-overview\"\u003e\n\u003ch2\u003eXL12T Timing Pulley — Precise Synchronous Drive for CNC, 3D Printers \u0026amp; Robotics\u003c\/h2\u003e\n\u003cp\u003eWhen a slipping or misaligned drive pulley derails your build mid-project, every minute of downtime costs you. Makers, engineers, and hobbyists who demand repeatable, slip-free motion need a timing pulley they can trust across long print runs, multi-axis CNC routines, and continuous robotics cycles. The XL12T AF synchronous wheel is engineered for exactly that workload.\u003c\/p\u003e\n\u003cp\u003eThis timing pulley features 12 teeth in the XL tooth profile and accepts a 10mm wide XL timing belt. Available bore sizes span 4mm, 5mm, 6mm, 6.35mm (1\/4\"), and 8mm — covering the most common motor shaft diameters from approximately 0.16\" to 0.31\". The AF (aluminum flange) construction provides a lightweight yet rigid hub that resists deformation under load.\u003c\/p\u003e\n\u003cp\u003eTypical use cases include CNC router X\/Y axis drives requiring consistent step accuracy, FDM 3D printer extruder and motion systems where belt skip causes layer shifts, and compact robotics arm joints where low backlash synchronous drive is essential for positional repeatability.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"hdiy-compat\"\u003e\n\u003cspan class=\"hdiy-compat-icon\"\u003e⚙️\u003c\/span\u003e Compatible with \u003cstrong\u003eXL-profile 10mm wide timing belts\u003c\/strong\u003e. Verify your motor shaft diameter matches the selected bore before ordering.\u003c\/div\u003e\n\u003cdiv class=\"hdiy-features\"\u003e\n\u003ch2\u003e✅ Key Features of These XL12T AF Timing Pulleys\u003c\/h2\u003e\n\u003cul class=\"hdiy-list\"\u003e\n\u003cli\u003e\n\u003cspan class=\"hdiy-icon\"\u003e🔩\u003c\/span\u003e \u003cstrong\u003e5 Bore Options in One Listing\u003c\/strong\u003e — Choose from 4mm, 5mm, 6mm, 6.35mm, or 8mm to match your motor shaft without adapters or machining.\u003c\/li\u003e\n\u003cli\u003e\n\u003cspan class=\"hdiy-icon\"\u003e📐\u003c\/span\u003e \u003cstrong\u003eXL 12-Tooth Profile\u003c\/strong\u003e — The XL tooth geometry delivers positive engagement with the belt, eliminating slip under variable torque loads common in CNC and motion control applications.\u003c\/li\u003e\n\u003cli\u003e\n\u003cspan class=\"hdiy-icon\"\u003e🏋️\u003c\/span\u003e \u003cstrong\u003e10mm Belt Width Compatibility\u003c\/strong\u003e — Matched to standard 10mm XL timing belts for straightforward sourcing and replacement without custom belt orders.\u003c\/li\u003e\n\u003cli\u003e\n\u003cspan class=\"hdiy-icon\"\u003e⚡\u003c\/span\u003e \u003cstrong\u003eAF Aluminum Flange Construction\u003c\/strong\u003e — The aluminum flange hub keeps rotational mass low while providing a secure, concentric grip on the shaft for accurate indexing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cspan class=\"hdiy-icon\"\u003e🔄\u003c\/span\u003e \u003cstrong\u003eLow Backlash Synchronous Drive\u003c\/strong\u003e — Toothed engagement means zero slip between pulley and belt, critical for layer-accurate 3D printing and repeatable CNC positioning.\u003c\/li\u003e\n\u003cli\u003e\n\u003cspan class=\"hdiy-icon\"\u003e🛠️\u003c\/span\u003e \u003cstrong\u003eDrop-In Replacement Fit\u003c\/strong\u003e — Standard XL12T dimensions allow direct substitution in existing drive systems without redesigning your motor mount or belt path.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"hdiy-table-wrap\"\u003e\n\u003ch2\u003e📐 Technical Specifications — XL12T Timing Pulley\u003c\/h2\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth\u003eTooth Profile\u003c\/th\u003e\n\u003ctd\u003eXL (Extra Light)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eNumber of Teeth\u003c\/th\u003e\n\u003ctd\u003e12\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eBelt Width\u003c\/th\u003e\n\u003ctd\u003e10mm (0.39\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eBore Diameter\u003c\/th\u003e\n\u003ctd\u003e4mm \/ 5mm \/ 6mm \/ 6.35mm \/ 8mm (see variant options)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eHub Style\u003c\/th\u003e\n\u003ctd\u003eAF (Aluminum Flange)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eMaterial\u003c\/th\u003e\n\u003ctd\u003eAluminum alloy\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003ePitch\u003c\/th\u003e\n\u003ctd\u003eXL — 5.08mm (0.200\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eOutside Diameter\u003c\/th\u003e\n\u003ctd\u003eSee variant options\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFlange Diameter\u003c\/th\u003e\n\u003ctd\u003eSee variant options\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eSet Screw\u003c\/th\u003e\n\u003ctd\u003eIncluded\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFinish\u003c\/th\u003e\n\u003ctd\u003eNatural anodized aluminum\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eCompatible Belt\u003c\/th\u003e\n\u003ctd\u003eXL-profile, 10mm width\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"hdiy-faq\"\u003e\n\u003ch2\u003e❓ Frequently Asked Questions\u003c\/h2\u003e\n\u003cdetails\u003e\n\u003csummary\u003eHow do I choose the right bore size for my motor shaft?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eMeasure your motor shaft diameter with a caliper. Common stepper motor shafts are 5mm or 8mm; servo motors often use 6mm or 6.35mm (1\/4\"). Select the bore that matches your shaft exactly — a loose fit will cause runout and positioning errors even with the set screw tightened.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eWhat belt does this pulley use?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eThis pulley is designed for XL-profile timing belts with a 10mm width and a 5.08mm (0.200\") pitch. Do not use GT2 or T5 belts — the tooth profiles are not interchangeable and will cause skipping or premature wear.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eIs this pulley strong enough for CNC router duty cycles?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eYes. The aluminum alloy construction handles the continuous torque and vibration loads typical of hobby and light-industrial CNC routers. For very high-speed spindle applications exceeding 5,000 RPM on the pulley, verify dynamic balance requirements with your system design.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eWill this pulley corrode if used in a humid workshop?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eAluminum naturally forms a protective oxide layer that resists corrosion in typical indoor workshop environments. The anodized finish adds an additional barrier. Avoid prolonged exposure to saltwater or strong acids, which can degrade aluminum over time.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eCan I use this pulley in a 3D printer motion system?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eYes, provided your printer uses XL-profile 10mm belts. Many CoreXY and Cartesian printers use GT2 belts — confirm your belt profile before ordering. If your printer uses XL belts on the X\/Y or Z axis, this pulley is a direct fit for 12-tooth positions.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eDoes the set screw come pre-installed?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eA set screw is included with each pulley. It is typically pre-installed in the hub. Use an appropriate hex key (Allen wrench) to tighten it against a flat on your motor shaft for the most secure connection. If your shaft has no flat, consider adding a small flat with a file for better grip.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eHow do I decide between the 6mm and 6.35mm bore options?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003e6mm is the standard metric shaft size used on most metric stepper and servo motors. 6.35mm (1\/4\") is the imperial equivalent common on North American servo motors and some DC gear motors. Check your motor's datasheet for the exact shaft diameter — even a 0.35mm mismatch will cause wobble under load.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"hdiy-cta\"\u003e🛒 Select your bore size above, then add to cart.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cp\u003e \u003c\/p\u003e","brand":"HomeDIYer","offers":[{"title":"4mm","offer_id":52444079096082,"sku":"GF3373-0","price":9.49,"currency_code":"USD","in_stock":true},{"title":"5mm","offer_id":52444079128850,"sku":"GF3373-1","price":5.79,"currency_code":"USD","in_stock":true},{"title":"6mm","offer_id":52444079161618,"sku":"GF3373-2","price":5.79,"currency_code":"USD","in_stock":true},{"title":"6.35mm","offer_id":52444079194386,"sku":"GF3373-3","price":6.85,"currency_code":"USD","in_stock":true},{"title":"8mm","offer_id":52444079227154,"sku":"GF3373-4","price":5.79,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0884\/8936\/1682\/files\/Main-03_4e525af1-a389-4e96-8d12-d4904620ab2f.jpg?v=1783263447","url":"https:\/\/homediyer.com\/products\/xl12t-timing-pulley-10mm-belt-af-synchronous-wheel","provider":"HomeDIYer","version":"1.0","type":"link"}