{"product_id":"module-4-0-spur-gear-10t-50t-teeth-45-steel-flat-gear-transmission-gear-for-cnc","title":"Module 4.0 Spur Gear 10T-50T Teeth 45# Steel Flat Gear Transmission Gear For CNC","description":"\u003cdiv class=\"hdiy-desc\"\u003e\n\n  \u003cdiv class=\"hdiy-overview\"\u003e\n    \u003ch2\u003eModule 4.0 Spur Gear — Precision 45# Steel Flat Gear for CNC \u0026amp; Industrial Drives\u003c\/h2\u003e\n    \u003cp\u003eWhen a stripped or undersized gear brings your CNC router, automated conveyor, or robotics build to a halt, you need a replacement that holds tolerance under load — not one that wears out in the first hundred cycles. Engineers, makers, and machine builders who demand repeatable accuracy turn to Module 4.0 spur gears machined from 45# carbon steel for their drive trains.\u003c\/p\u003e\n    \u003cp\u003eThis listing covers a complete range of Module 4.0 flat spur gears spanning 10T through 50T tooth counts. Each gear is machined from 45# medium-carbon steel (equivalent to SAE 1045), offering a tensile strength typically in the 600–800 MPa range before any additional heat treatment. Tooth pitch diameter scales with tooth count at 4 mm per tooth (e.g., 10T = 40 mm \/ 1.57 in PD; 25T = 100 mm \/ 3.94 in PD; 50T = 200 mm \/ 7.87 in PD). Bore diameter and keyway dimensions vary by tooth count — see variant options for exact bore specs.\u003c\/p\u003e\n    \u003cp\u003eTypical use cases include CNC milling machine Z-axis drives requiring consistent backlash control, open-frame 3D printer extruder gear trains where module 4.0 spur gears for RepRap-style builds are needed, and light industrial conveyor reduction stages where a flat spur gear transmission gear for automation lines must mesh reliably with a matching pinion.\u003c\/p\u003e\n  \u003c\/div\u003e\n\n  \u003cdiv class=\"hdiy-compat\"\u003e\n    \u003cspan class=\"hdiy-compat-icon\"\u003e⚙️\u003c\/span\u003e\n    \u003cstrong\u003eCompatibility:\u003c\/strong\u003e Meshes with any Module 4.0 (Mod 4) spur gear, rack, or pinion. Confirm bore diameter and keyway dimensions match your shaft before ordering.\n  \u003c\/div\u003e\n\n  \u003ch2\u003e✅ Key Features of These Module 4.0 Spur Gears\u003c\/h2\u003e\n  \u003cdiv class=\"hdiy-features\"\u003e\n    \u003cdiv\u003e\n      \u003cspan class=\"hdiy-icon\"\u003e🔩\u003c\/span\u003e\n      \u003cstrong\u003e45# Carbon Steel Construction\u003c\/strong\u003e\n      \u003cp\u003eMachined from 45# medium-carbon steel for a balance of machinability and load-bearing strength, suitable for moderate-to-heavy drive applications.\u003c\/p\u003e\n    \u003c\/div\u003e\n    \u003cdiv\u003e\n      \u003cspan class=\"hdiy-icon\"\u003e📐\u003c\/span\u003e\n      \u003cstrong\u003eTrue Module 4.0 Tooth Profile\u003c\/strong\u003e\n      \u003cp\u003eInvolute tooth geometry cut to Module 4.0 standard ensures smooth meshing and interchangeability with any Mod 4 mating gear or rack.\u003c\/p\u003e\n    \u003c\/div\u003e\n    \u003cdiv\u003e\n      \u003cspan class=\"hdiy-icon\"\u003e🎯\u003c\/span\u003e\n      \u003cstrong\u003eWide Tooth Count Selection (10T–50T)\u003c\/strong\u003e\n      \u003cp\u003e40 tooth-count variants in a single listing let you dial in the exact gear ratio your drive system requires without sourcing from multiple suppliers.\u003c\/p\u003e\n    \u003c\/div\u003e\n    \u003cdiv\u003e\n      \u003cspan class=\"hdiy-icon\"\u003e🔄\u003c\/span\u003e\n      \u003cstrong\u003eFlat Spur Gear Design\u003c\/strong\u003e\n      \u003cp\u003eParallel-axis flat gear profile transmits torque efficiently with minimal axial thrust, ideal for compact gearbox assemblies and open-frame machine builds.\u003c\/p\u003e\n    \u003c\/div\u003e\n    \u003cdiv\u003e\n      \u003cspan class=\"hdiy-icon\"\u003e🏭\u003c\/span\u003e\n      \u003cstrong\u003eCNC \u0026amp; Industrial Drive Ready\u003c\/strong\u003e\n      \u003cp\u003eDimensioned for direct drop-in use on CNC routers, laser cutters, conveyor reduction stages, and robotics joint drives where a reliable transmission gear is critical.\u003c\/p\u003e\n    \u003c\/div\u003e\n    \u003cdiv\u003e\n      \u003cspan class=\"hdiy-icon\"\u003e📦\u003c\/span\u003e\n      \u003cstrong\u003eSingle-Piece Packaging\u003c\/strong\u003e\n      \u003cp\u003eEach order ships as 1 PCS, letting you order exactly the quantity you need for prototyping, replacement, or small-batch production runs.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n  \u003ch2\u003e📐 Technical Specifications — Module 4.0 Spur Gear\u003c\/h2\u003e\n  \u003cdiv class=\"hdiy-table-wrap\"\u003e\n    \u003ctable\u003e\n      \u003ctbody\u003e\n        \u003ctr\u003e\n\u003cth\u003eModule\u003c\/th\u003e\n\u003ctd\u003e4.0 (Mod 4)\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eTooth Count Range\u003c\/th\u003e\n\u003ctd\u003e10T – 50T (see variant options)\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eMaterial\u003c\/th\u003e\n\u003ctd\u003e45# Carbon Steel (SAE 1045 equivalent)\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eGear Type\u003c\/th\u003e\n\u003ctd\u003eFlat Spur Gear (parallel axis, involute profile)\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003ePitch Diameter\u003c\/th\u003e\n\u003ctd\u003eModule × Teeth (e.g., 4 × 20T = 80 mm \/ 3.15 in)\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003ePressure Angle\u003c\/th\u003e\n\u003ctd\u003e20° (standard involute)\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eBore Diameter\u003c\/th\u003e\n\u003ctd\u003eSee variant options\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eHub \/ Face Width\u003c\/th\u003e\n\u003ctd\u003eSee variant options\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eSurface Finish\u003c\/th\u003e\n\u003ctd\u003eMachined, natural steel (no coating unless noted)\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003ePacking Quantity\u003c\/th\u003e\n\u003ctd\u003e1 PCS per order\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eApplication\u003c\/th\u003e\n\u003ctd\u003eCNC machines, robotics, conveyor drives, automation\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003c\/tbody\u003e\n    \u003c\/table\u003e\n  \u003c\/div\u003e\n\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 tooth count for my application?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eGear ratio is determined by dividing the driven gear tooth count by the driving gear tooth count. For example, pairing a 10T pinion with a 40T gear gives a 4:1 reduction. Calculate the ratio your drive system requires, then select the tooth count that achieves it while keeping the center distance within your frame constraints (center distance = Module × (T1 + T2) \/ 2).\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n    \u003cdetails\u003e\n      \u003csummary\u003eWhat load can a Module 4.0 45# steel spur gear handle?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003e45# carbon steel has a typical tensile strength of 600–800 MPa in the as-machined condition. Actual load capacity depends on tooth count, face width, operating speed, and lubrication. For high-cycle or high-torque applications, consider specifying heat-treated variants or consult a mechanical engineer for a formal gear strength calculation (AGMA or ISO 6336).\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n    \u003cdetails\u003e\n      \u003csummary\u003eIs 45# steel corrosion resistant?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003e45# carbon steel is not inherently corrosion resistant. For outdoor, humid, or washdown environments, apply a suitable lubricant or protective coating (e.g., grease, oil, or zinc spray). For applications requiring inherent corrosion resistance, consider stainless steel gears instead.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n    \u003cdetails\u003e\n      \u003csummary\u003eWill this gear mesh with my existing Module 4.0 rack or pinion?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eYes — any two gears sharing the same module and pressure angle will mesh correctly. These gears use Module 4.0 with a standard 20° pressure angle, so they are interchangeable with any Mod 4 \/ 20° rack, pinion, or mating spur gear regardless of brand, as long as the tooth count combination gives you the center distance your frame allows.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n    \u003cdetails\u003e\n      \u003csummary\u003eHow do I confirm the bore diameter fits my shaft?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eBore diameter varies by tooth count and is listed in the variant detail page. Measure your shaft diameter with a caliper before ordering. If the bore is slightly larger than your shaft, a keyway and set screw arrangement or a shaft collar can take up the slack. If the bore is smaller, the gear cannot be installed without machining — contact us to confirm bore specs for your selected tooth count.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n    \u003cdetails\u003e\n      \u003csummary\u003eCan I use these gears in a CNC router or laser cutter drive system?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eYes. Module 4.0 spur gears are commonly used in CNC router rack-and-pinion drive systems, laser cutter gantry drives, and similar motion control applications. Ensure the pinion tooth count and motor torque are matched to your required feed rate and cutting force. A 20T–25T pinion paired with a Mod 4 rack is a common starting point for desktop CNC builds.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n    \u003cdetails\u003e\n      \u003csummary\u003eDo I need to lubricate these gears during operation?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eYes. Steel-on-steel gear meshes benefit from lubrication to reduce wear and operating temperature. A light machine oil or lithium-based grease applied to the tooth flanks at installation and periodically during service will significantly extend gear life, especially in continuous-duty or high-speed applications.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n  \u003c\/div\u003e\n\n  \u003cdiv class=\"hdiy-cta\"\u003e\n    🛒 Select your \u003cstrong\u003eModel \u0026amp; Teeth\u003c\/strong\u003e above, then add to cart.\n  \u003c\/div\u003e\n\n\u003c\/div\u003e\n\n\u003cscript type=\"application\/ld+json\"\u003e\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"FAQPage\",\n  \"mainEntity\": [\n    {\n      \"@type\": \"Question\",\n      \"name\": \"How do I choose the right tooth count for my application?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Gear ratio is determined by dividing the driven gear tooth count by the driving gear tooth count. For example, pairing a 10T pinion with a 40T gear gives a 4:1 reduction. Calculate the ratio your drive system requires, then select the tooth count that achieves it while keeping the center distance within your frame constraints (center distance = Module × (T1 + T2) \/ 2).\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What load can a Module 4.0 45# steel spur gear handle?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"45# carbon steel has a typical tensile strength of 600–800 MPa in the as-machined condition. Actual load capacity depends on tooth count, face width, operating speed, and lubrication. For high-cycle or high-torque applications, consider specifying heat-treated variants or consult a mechanical engineer for a formal gear strength calculation.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Is 45# steel corrosion resistant?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"45# carbon steel is not inherently corrosion resistant. For outdoor, humid, or washdown environments, apply a suitable lubricant or protective coating. For applications requiring inherent corrosion resistance, consider stainless steel gears instead.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Will this gear mesh with my existing Module 4.0 rack or pinion?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Yes — any two gears sharing the same module and pressure angle will mesh correctly. These gears use Module 4.0 with a standard 20° pressure angle, so they are interchangeable with any Mod 4 \/ 20° rack, pinion, or mating spur gear.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"How do I confirm the bore diameter fits my shaft?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Bore diameter varies by tooth count and is listed in the variant detail page. Measure your shaft diameter with a caliper before ordering. Contact us to confirm bore specs for your selected tooth count.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Can I use these gears in a CNC router or laser cutter drive system?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Yes. Module 4.0 spur gears are commonly used in CNC router rack-and-pinion drive systems, laser cutter gantry drives, and similar motion control applications.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Do I need to lubricate these gears during operation?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Yes. Steel-on-steel gear meshes benefit from lubrication to reduce wear and operating temperature. A light machine oil or lithium-based grease applied to the tooth flanks at installation and periodically during service will significantly extend gear life.\"\n      }\n    }\n  ]\n}\n\u003c\/script\u003e","brand":"HomeDIYer","offers":[{"title":"4M 10T \/ 1 PCS","offer_id":52442841547026,"sku":"Adaah058241x1","price":13.71,"currency_code":"USD","in_stock":true},{"title":"4M 11T \/ 1 PCS","offer_id":52442841579794,"sku":"Adaah058242x1","price":15.26,"currency_code":"USD","in_stock":true},{"title":"4M 12T \/ 1 PCS","offer_id":52442841612562,"sku":"Adaah058243x1","price":19.04,"currency_code":"USD","in_stock":true},{"title":"4M 13T \/ 1 PCS","offer_id":52442841645330,"sku":"Adaah058244x1","price":20.44,"currency_code":"USD","in_stock":true},{"title":"4M 14T \/ 1 PCS","offer_id":52442841678098,"sku":"Adaah058245x1","price":27.53,"currency_code":"USD","in_stock":true},{"title":"4M 15T \/ 1 PCS","offer_id":52442841710866,"sku":"Adaah058246x1","price":27.95,"currency_code":"USD","in_stock":true},{"title":"4M 16T \/ 1 PCS","offer_id":52442841743634,"sku":"Adaah058247x1","price":31.13,"currency_code":"USD","in_stock":true},{"title":"4M 17T \/ 1 PCS","offer_id":52442841776402,"sku":"Adaah058248x1","price":33.52,"currency_code":"USD","in_stock":true},{"title":"4M 18T \/ 1 PCS","offer_id":52442841809170,"sku":"Adaah058249x1","price":42.36,"currency_code":"USD","in_stock":true},{"title":"4M 19T \/ 1 PCS","offer_id":52442841841938,"sku":"Adaah058250x1","price":45.08,"currency_code":"USD","in_stock":true},{"title":"4M 20T \/ 1 PCS","offer_id":52442841874706,"sku":"Adaah058251x1","price":45.36,"currency_code":"USD","in_stock":true},{"title":"4M 21T \/ 1 PCS","offer_id":52442841907474,"sku":"Adaah058252x1","price":54.52,"currency_code":"USD","in_stock":true},{"title":"4M 22T \/ 1 PCS","offer_id":52442841940242,"sku":"Adaah058253x1","price":58.06,"currency_code":"USD","in_stock":true},{"title":"4M 23T \/ 1 PCS","offer_id":52442841973010,"sku":"Adaah058254x1","price":60.23,"currency_code":"USD","in_stock":true},{"title":"4M 24T \/ 1 PCS","offer_id":52442842005778,"sku":"Adaah058255x1","price":62.68,"currency_code":"USD","in_stock":true},{"title":"4M 25T \/ 1 PCS","offer_id":52442842038546,"sku":"Adaah058256x1","price":81.31,"currency_code":"USD","in_stock":true},{"title":"4M 26T \/ 1 PCS","offer_id":52442842071314,"sku":"Adaah058257x1","price":87.16,"currency_code":"USD","in_stock":true},{"title":"4M 27T \/ 1 PCS","offer_id":52442842104082,"sku":"Adaah058258x1","price":94.59,"currency_code":"USD","in_stock":true},{"title":"4M 28T \/ 1 PCS","offer_id":52442842136850,"sku":"Adaah058259x1","price":100.22,"currency_code":"USD","in_stock":true},{"title":"4M 29T \/ 1 PCS","offer_id":52442842169618,"sku":"Adaah058260x1","price":107.56,"currency_code":"USD","in_stock":true},{"title":"4M 31T \/ 1 PCS","offer_id":52442842202386,"sku":"Adaah058261x1","price":118.85,"currency_code":"USD","in_stock":true},{"title":"4M 30T \/ 1 PCS","offer_id":52442842235154,"sku":"Adaah058262x1","price":114.09,"currency_code":"USD","in_stock":true},{"title":"4M 32T \/ 1 PCS","offer_id":52442842267922,"sku":"Adaah058263x1","price":130.0,"currency_code":"USD","in_stock":true},{"title":"4M 33T \/ 1 PCS","offer_id":52442842300690,"sku":"Adaah058264x1","price":130.55,"currency_code":"USD","in_stock":true},{"title":"4M 34T \/ 1 PCS","offer_id":52442842333458,"sku":"Adaah058265x1","price":141.37,"currency_code":"USD","in_stock":true},{"title":"4M 35T \/ 1 PCS","offer_id":52442842366226,"sku":"Adaah058266x1","price":150.27,"currency_code":"USD","in_stock":true},{"title":"4M 36T \/ 1 PCS","offer_id":52442842398994,"sku":"Adaah058267x1","price":159.92,"currency_code":"USD","in_stock":true},{"title":"4M 37T \/ 1 PCS","offer_id":52442842431762,"sku":"Adaah058268x1","price":169.66,"currency_code":"USD","in_stock":true},{"title":"4M 38T \/ 1 PCS","offer_id":52442842464530,"sku":"Adaah058269x1","price":174.88,"currency_code":"USD","in_stock":true},{"title":"4M 39T \/ 1 PCS","offer_id":52442842497298,"sku":"Adaah058270x1","price":185.9,"currency_code":"USD","in_stock":true},{"title":"4M 40T \/ 1 PCS","offer_id":52442842530066,"sku":"Adaah058271x1","price":195.69,"currency_code":"USD","in_stock":true},{"title":"4M 41T \/ 1 PCS","offer_id":52442842562834,"sku":"Adaah058272x1","price":205.21,"currency_code":"USD","in_stock":true},{"title":"4M 42T \/ 1 PCS","offer_id":52442842595602,"sku":"Adaah058273x1","price":215.0,"currency_code":"USD","in_stock":true},{"title":"4M 43T \/ 1 PCS","offer_id":52442842628370,"sku":"Adaah058274x1","price":225.83,"currency_code":"USD","in_stock":true},{"title":"4M 44T \/ 1 PCS","offer_id":52442842661138,"sku":"Adaah058275x1","price":234.8,"currency_code":"USD","in_stock":true},{"title":"4M 45T \/ 1 PCS","offer_id":52442842693906,"sku":"Adaah058276x1","price":244.73,"currency_code":"USD","in_stock":true},{"title":"4M 46T \/ 1 PCS","offer_id":52442842726674,"sku":"Adaah058277x1","price":254.71,"currency_code":"USD","in_stock":true},{"title":"4M 48T \/ 1 PCS","offer_id":52442842759442,"sku":"Adaah058278x1","price":275.79,"currency_code":"USD","in_stock":true},{"title":"4M 47T \/ 1 PCS","offer_id":52442842792210,"sku":"Adaah058279x1","price":264.51,"currency_code":"USD","in_stock":true},{"title":"4M 50T \/ 1 PCS","offer_id":52442842824978,"sku":"Adaah058280x1","price":294.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0884\/8936\/1682\/files\/Picture1of9_8aa807b7-3cbf-483a-b0e4-a28eaf30115e.jpg?v=1783615933","url":"https:\/\/homediyer.com\/products\/module-4-0-spur-gear-10t-50t-teeth-45-steel-flat-gear-transmission-gear-for-cnc","provider":"HomeDIYer","version":"1.0","type":"link"}