{"product_id":"htd-3m-closed-loop-timing-belt-339-345-354-363-381mm","title":"HTD 3M Closed Loop Timing Belt — 339 \/ 345 \/ 354 \/ 363 \/ 381mm Length, 10 \/ 15 \/ 20mm Width","description":"\u003cp\u003e \u003c\/p\u003e\n\u003cdiv class=\"hdiy-desc\"\u003e\n\u003cdiv class=\"hdiy-overview\"\u003e\n\u003ch2\u003eHTD 3M Closed Loop Timing Belt — Precise Synchronous Drive for 3D Printers, CNC \u0026amp; Robotics\u003c\/h2\u003e\n\u003cp\u003eA worn or incorrectly sized belt is one of the most common causes of layer shifting in 3D printers, axis drift in small CNC machines, and positioning errors in robotics builds. For makers, engineers, and repair technicians who need a reliable drop-in replacement or a new HTD 3M closed loop timing belt for a compact synchronous drive system, this listing covers the most commonly needed lengths and widths in one place.\u003c\/p\u003e\n\u003cp\u003eEach order includes one closed-loop synchronous belt in the HTD 3M profile (3mm pitch, rounded tooth form). Available inner circumference lengths are 339mm (≈13.3\"), 345mm (≈13.6\"), 354mm (≈13.9\"), 363mm (≈14.3\"), and 381mm (≈15.0\"). Width options are 10mm (≈0.39\"), 15mm (≈0.59\"), and 20mm (≈0.79\"). Construction is typically neoprene rubber with a fiberglass or steel cord tensile layer for stretch resistance under cyclic load. Sold individually (1 pc per order).\u003c\/p\u003e\n\u003cp\u003eTypical use cases include \u003cstrong\u003e3D printer drive systems\u003c\/strong\u003e (CoreXY, delta, and bed-slinger configurations), \u003cstrong\u003ecompact CNC router and laser engraver axis drives\u003c\/strong\u003e, and \u003cstrong\u003erobotics and automation\u003c\/strong\u003e builds where a small-pitch HTD 3M synchronous belt drive is required for precise, slip-free motion control.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"hdiy-compat\"\u003e\n\u003cspan class=\"hdiy-compat-icon\"\u003eℹ️\u003c\/span\u003e \u003cstrong\u003eCompatibility:\u003c\/strong\u003e Fits \u003cstrong\u003eHTD 3M profile pulleys only\u003c\/strong\u003e (3mm pitch, rounded tooth). Not compatible with GT2, MXL, XL, T2.5, T5, or other profiles. Confirm your pulley profile before ordering.\u003c\/div\u003e\n\u003ch2\u003e✅ Key Features of These HTD 3M Closed Loop Timing Belts\u003c\/h2\u003e\n\u003cul class=\"hdiy-features\"\u003e\n\u003cli\u003e\n\u003cspan class=\"hdiy-icon\"\u003e🔁\u003c\/span\u003e\u003cspan\u003e\u003cstrong\u003eSeamless Closed-Loop Design\u003c\/strong\u003e — Endless loop construction has no splice or joint, delivering consistent tension and smooth power transmission throughout the full belt circumference.\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cspan class=\"hdiy-icon\"\u003e⚙️\u003c\/span\u003e\u003cspan\u003e\u003cstrong\u003eHTD 3M Rounded Tooth Profile\u003c\/strong\u003e — The 3mm-pitch rounded HTD tooth form provides positive, slip-free engagement with HTD 3M pulleys, reducing the risk of tooth jump in compact synchronous drive applications.\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cspan class=\"hdiy-icon\"\u003e📏\u003c\/span\u003e\u003cspan\u003e\u003cstrong\u003eFive Length Options\u003c\/strong\u003e — Inner circumferences of 339, 345, 354, 363, and 381mm cover a range of pulley center distances, making it straightforward to find a direct replacement HTD 3M belt without custom fabrication.\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cspan class=\"hdiy-icon\"\u003e📐\u003c\/span\u003e\u003cspan\u003e\u003cstrong\u003eThree Width Options\u003c\/strong\u003e — Choose 10mm, 15mm, or 20mm to match your pulley face; wider belts distribute load across more tooth contact area, useful in higher-torque 3M timing belt drive setups.\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cspan class=\"hdiy-icon\"\u003e🧱\u003c\/span\u003e\u003cspan\u003e\u003cstrong\u003eReinforced Tensile Core\u003c\/strong\u003e — Fiberglass or steel cord reinforcement (typical for this belt class) resists elongation under repeated loading, helping maintain positional accuracy in 3D printer and robotics belt drive systems over time.\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cspan class=\"hdiy-icon\"\u003e🔧\u003c\/span\u003e\u003cspan\u003e\u003cstrong\u003eWide Application Range\u003c\/strong\u003e — Suited for 3D printers, laser engravers, small CNC routers, conveyor systems, and DIY automation projects that use standard HTD 3M synchronous pulleys.\u003c\/span\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003e📐 Technical Specifications — HTD 3M Closed Loop Timing Belt\u003c\/h2\u003e\n\u003cdiv class=\"hdiy-table-wrap\"\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth\u003eBelt Profile\u003c\/th\u003e\n\u003ctd\u003eHTD 3M (High Torque Drive, 3mm pitch)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eTooth Form\u003c\/th\u003e\n\u003ctd\u003eRounded (HTD standard)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eAvailable Lengths (Inner Circumference)\u003c\/th\u003e\n\u003ctd\u003e339mm (≈13.3\") \/ 345mm (≈13.6\") \/ 354mm (≈13.9\") \/ 363mm (≈14.3\") \/ 381mm (≈15.0\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eAvailable Widths\u003c\/th\u003e\n\u003ctd\u003e10mm (≈0.39\") \/ 15mm (≈0.59\") \/ 20mm (≈0.79\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003ePitch\u003c\/th\u003e\n\u003ctd\u003e3mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eNumber of Teeth\u003c\/th\u003e\n\u003ctd\u003e113 teeth (339mm) \/ 115 teeth (345mm) \/ 118 teeth (354mm) \/ 121 teeth (363mm) \/ 127 teeth (381mm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eBelt Type\u003c\/th\u003e\n\u003ctd\u003eClosed loop (endless)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eMaterial\u003c\/th\u003e\n\u003ctd\u003eNeoprene rubber body, fiberglass or steel cord tensile layer (typical)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eColor\u003c\/th\u003e\n\u003ctd\u003eBlack\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eCompatible Pulley Profile\u003c\/th\u003e\n\u003ctd\u003eHTD 3M only\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003ePack Quantity\u003c\/th\u003e\n\u003ctd\u003e1 pc per order\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eOperating Temperature\u003c\/th\u003e\n\u003ctd\u003eSee variant options \/ Contact us to confirm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eMax Load Rating\u003c\/th\u003e\n\u003ctd\u003eSee variant options \/ Contact us to confirm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"hdiy-note\"\u003e\n\u003cspan class=\"hdiy-note-icon\"\u003e⚠️\u003c\/span\u003e \u003cstrong\u003eSpec Note:\u003c\/strong\u003e Operating temperature range and maximum load ratings vary by exact construction batch. Contact us if your application has specific environmental or load requirements.\u003c\/div\u003e\n\u003ch2\u003e❓ Frequently Asked Questions\u003c\/h2\u003e\n\u003cdiv class=\"hdiy-faq\"\u003e\n\u003cdetails\u003e\n\u003csummary\u003eHow do I choose the right belt length and width?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eThe belt length is the \u003cstrong\u003einner circumference\u003c\/strong\u003e of the closed loop. Available lengths are \u003cstrong\u003e339mm (≈13.3\")\u003c\/strong\u003e, \u003cstrong\u003e345mm (≈13.6\")\u003c\/strong\u003e, \u003cstrong\u003e354mm (≈13.9\")\u003c\/strong\u003e, \u003cstrong\u003e363mm (≈14.3\")\u003c\/strong\u003e, and \u003cstrong\u003e381mm (≈15.0\")\u003c\/strong\u003e. Measure your existing belt's inner circumference, or estimate from your pulley center distance: \u003cem\u003eL ≈ 2C + π(D₁+D₂)\/2\u003c\/em\u003e. Choose the width — 10mm, 15mm, or 20mm — to match your pulley face width.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eWhat load or torque can an HTD 3M timing belt handle?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eHTD 3M belts are generally suited for light-to-moderate torque synchronous drive applications. Wider belts (20mm) typically carry higher loads than narrower ones (10mm). For precise torque ratings, consult your drive system's engineering specifications or contact us directly.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eCan these belts be used outdoors or in damp environments?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eHTD 3M belts are typically constructed from neoprene rubber, which offers reasonable resistance to moisture and mild environmental exposure. Prolonged UV exposure or contact with oils and chemicals may degrade the belt over time. For demanding outdoor use, verify the material composition with us before installation.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eAre these belts compatible with standard HTD 3M pulleys?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eYes. These belts conform to the HTD 3M profile standard — \u003cstrong\u003e3mm pitch, rounded tooth form\u003c\/strong\u003e. They are compatible with any standard HTD 3M timing pulley. They are \u003cstrong\u003enot\u003c\/strong\u003e interchangeable with GT2, MXL, XL, T2.5, T5, or other belt profiles.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eHow do I know which length — 339, 345, 354, 363, or 381mm — I need?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eMeasure the inner circumference of your existing belt, or use the formula \u003cem\u003eL ≈ 2C + π(D₁+D₂)\/2\u003c\/em\u003e where C is the center-to-center distance between pulleys and D₁\/D₂ are the pulley pitch diameters. Select the closest available length from the five options listed above.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eWhat machines or projects are HTD 3M closed loop belts used for?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eHTD 3M closed loop timing belts are commonly used in \u003cstrong\u003e3D printers\u003c\/strong\u003e (CoreXY, delta, bed-slinger), \u003cstrong\u003esmall CNC machines\u003c\/strong\u003e, \u003cstrong\u003elaser engravers\u003c\/strong\u003e, \u003cstrong\u003erobotics\u003c\/strong\u003e, and compact DIY power transmission systems where a small belt pitch and precise synchronous motion are required.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eCan I use a wider belt on a narrower pulley?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eIn general, the belt width should match or be slightly narrower than the pulley face width. Using a belt significantly wider than the pulley is not recommended — it can cause uneven tooth engagement and tracking issues. A belt slightly narrower than the pulley face is typically acceptable in most drive configurations.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"hdiy-cta\"\u003e🛒 Select your \u003cstrong\u003ebelt length and width\u003c\/strong\u003e above, then add to cart — ships from our US warehouse.\u003c\/div\u003e\n\u003c\/div\u003e","brand":"HomeDIYer","offers":[{"title":"3M-345 \/ 10mm \/ 1Pcs","offer_id":52367693840658,"sku":"GF2164-0","price":3.93,"currency_code":"USD","in_stock":true},{"title":"3M-345 \/ 20mm \/ 1Pcs","offer_id":52367693873426,"sku":"GF2164-1","price":5.78,"currency_code":"USD","in_stock":true},{"title":"3M-363 \/ 10mm \/ 1Pcs","offer_id":52367693906194,"sku":"GF2164-2","price":3.93,"currency_code":"USD","in_stock":true},{"title":"3M-339 \/ 10mm \/ 1Pcs","offer_id":52367693938962,"sku":"GF2164-3","price":3.93,"currency_code":"USD","in_stock":true},{"title":"3M-354 \/ 10mm \/ 1Pcs","offer_id":52367693971730,"sku":"GF2164-4","price":3.93,"currency_code":"USD","in_stock":true},{"title":"3M-381 \/ 10mm \/ 1Pcs","offer_id":52367694004498,"sku":"GF2164-5","price":3.93,"currency_code":"USD","in_stock":true},{"title":"3M-345 \/ 15mm \/ 1Pcs","offer_id":52367694037266,"sku":"GF2164-6","price":5.02,"currency_code":"USD","in_stock":true},{"title":"3M-363 \/ 15mm \/ 1Pcs","offer_id":52367694070034,"sku":"GF2164-7","price":5.02,"currency_code":"USD","in_stock":true},{"title":"3M-339 \/ 15mm \/ 1Pcs","offer_id":52367694102802,"sku":"GF2164-8","price":5.02,"currency_code":"USD","in_stock":true},{"title":"3M-354 \/ 15mm \/ 1Pcs","offer_id":52367694135570,"sku":"GF2164-9","price":5.02,"currency_code":"USD","in_stock":true},{"title":"3M-381 \/ 15mm \/ 1Pcs","offer_id":52367694168338,"sku":"GF2164-10","price":5.02,"currency_code":"USD","in_stock":true},{"title":"3M-363 \/ 20mm \/ 1Pcs","offer_id":52367694201106,"sku":"GF2164-11","price":5.78,"currency_code":"USD","in_stock":true},{"title":"3M-339 \/ 20mm \/ 1Pcs","offer_id":52367694233874,"sku":"GF2164-12","price":5.78,"currency_code":"USD","in_stock":true},{"title":"3M-354 \/ 20mm \/ 1Pcs","offer_id":52367694266642,"sku":"GF2164-13","price":5.78,"currency_code":"USD","in_stock":true},{"title":"3M-381 \/ 20mm \/ 1Pcs","offer_id":52367694299410,"sku":"GF2164-14","price":5.78,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0884\/8936\/1682\/files\/Picture1of5_5eff317c-f248-435e-a19e-4bf8deea7396.jpg?v=1781437699","url":"https:\/\/homediyer.com\/de\/products\/htd-3m-closed-loop-timing-belt-339-345-354-363-381mm","provider":"HomeDIYer","version":"1.0","type":"link"}