{"product_id":"0-5-mod-brass-pinion-spur-gear-20t-bore-4-5-6mm","title":"0.5 Mod Brass Pinion Spur Gear 20 Teeth Bore 4\/5\/6mm Motor Transmission Gear","description":"\u003cdiv class=\"hdiy-desc\"\u003e\n\n  \u003cdiv class=\"hdiy-overview\"\u003e\n    \u003ch2\u003e0.5 Mod Brass Pinion Spur Gear — Precision 20-Tooth Motor Transmission Gear for Tight Drive Trains\u003c\/h2\u003e\n    \u003cp\u003eWhen a stripped plastic gear or an imprecise bore fit derails your build, the entire drivetrain pays the price. Hobbyists, robotics engineers, and RC vehicle builders who demand repeatable torque transfer and dimensional accuracy need a gear that holds tolerance under load — not one that wobbles or wears out after a few hundred cycles.\u003c\/p\u003e\n    \u003cp\u003eThis 0.5 module brass pinion spur gear features 20 teeth and is available in three bore diameters: 4 mm (~0.157 in), 5 mm (~0.197 in), and 6 mm (~0.236 in). The gear body is machined from brass, offering a balance of machinability, moderate corrosion resistance, and low-friction meshing. Overall gear outer diameter is approximately 11 mm (~0.433 in) at 0.5 mod \/ 20T geometry, with face width typically in the 5–8 mm range depending on variant.\u003c\/p\u003e\n    \u003cp\u003eTypical use cases include: miniature RC car and truck motor pinion replacement, small robotic arm joint drives requiring a 0.5 mod gear mesh, and compact automation mechanisms such as camera pan\/tilt rigs or conveyor micro-drives where a 20-tooth brass spur gear keeps noise and backlash low.\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 0.5 module spur or rack gear. Verify motor shaft diameter matches selected bore (4 mm \/ 5 mm \/ 6 mm) before ordering.\n  \u003c\/div\u003e\n\n  \u003cdiv class=\"hdiy-features\"\u003e\n    \u003ch2\u003e✅ Key Features of These 0.5 Mod Brass Pinion Spur Gears\u003c\/h2\u003e\n    \u003cul class=\"hdiy-list\"\u003e\n      \u003cli\u003e\n        \u003cspan class=\"hdiy-icon\"\u003e🔩\u003c\/span\u003e\n        \u003cstrong\u003eBrass Construction\u003c\/strong\u003e — Machines cleanly, resists galling against steel pinions, and provides adequate corrosion resistance for indoor and light-outdoor applications.\n      \u003c\/li\u003e\n      \u003cli\u003e\n        \u003cspan class=\"hdiy-icon\"\u003e📐\u003c\/span\u003e\n        \u003cstrong\u003e0.5 Module \/ 20-Tooth Geometry\u003c\/strong\u003e — Standard metric module ensures direct interchangeability with any 0.5 mod mating gear or rack without custom modification.\n      \u003c\/li\u003e\n      \u003cli\u003e\n        \u003cspan class=\"hdiy-icon\"\u003e🎯\u003c\/span\u003e\n        \u003cstrong\u003eThree Bore Options (4 \/ 5 \/ 6 mm)\u003c\/strong\u003e — Select the bore that matches your motor shaft exactly; no reaming or adapters required for standard shaft sizes.\n      \u003c\/li\u003e\n      \u003cli\u003e\n        \u003cspan class=\"hdiy-icon\"\u003e📦\u003c\/span\u003e\n        \u003cstrong\u003eFlexible Pack Quantities (1 \/ 2 \/ 5 \/ 10 PCS)\u003c\/strong\u003e — Order a single gear for a repair or stock up in bulk for prototyping runs — pricing scales with quantity.\n      \u003c\/li\u003e\n      \u003cli\u003e\n        \u003cspan class=\"hdiy-icon\"\u003e⚡\u003c\/span\u003e\n        \u003cstrong\u003eLow-Backlash Meshing\u003c\/strong\u003e — Machined tooth profile maintains consistent center distance and minimizes positional error in servo and stepper motor applications.\n      \u003c\/li\u003e\n      \u003cli\u003e\n        \u003cspan class=\"hdiy-icon\"\u003e🔄\u003c\/span\u003e\n        \u003cstrong\u003eBroad Application Range\u003c\/strong\u003e — Suited for RC vehicles, desktop robotics, 3D printer extruder drives, camera sliders, and other compact motorized mechanisms requiring a reliable 20T spur gear.\n      \u003c\/li\u003e\n    \u003c\/ul\u003e\n  \u003c\/div\u003e\n\n  \u003cdiv class=\"hdiy-table-wrap\"\u003e\n    \u003ch2\u003e📐 Technical Specifications — 0.5 Mod Brass Spur Gear\u003c\/h2\u003e\n    \u003ctable\u003e\n      \u003ctbody\u003e\n        \u003ctr\u003e\n\u003cth\u003eModule\u003c\/th\u003e\n\u003ctd\u003e0.5\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eNumber of Teeth\u003c\/th\u003e\n\u003ctd\u003e20T\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eBore Diameter\u003c\/th\u003e\n\u003ctd\u003e4 mm \/ 5 mm \/ 6 mm (see variant options)\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eOuter Diameter (approx.)\u003c\/th\u003e\n\u003ctd\u003e~11 mm (~0.433 in)\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eFace Width\u003c\/th\u003e\n\u003ctd\u003eSee variant options\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eMaterial\u003c\/th\u003e\n\u003ctd\u003eBrass\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eGear Type\u003c\/th\u003e\n\u003ctd\u003eSpur Gear (Pinion)\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003ePressure Angle\u003c\/th\u003e\n\u003ctd\u003e20°\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003ePacking Quantity\u003c\/th\u003e\n\u003ctd\u003e1 \/ 2 \/ 5 \/ 10 PCS (see variant options)\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eWeight (per piece, approx.)\u003c\/th\u003e\n\u003ctd\u003eSee variant options\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\n    \u003cdetails\u003e\n      \u003csummary\u003eHow do I choose the right bore size — 4 mm, 5 mm, or 6 mm?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eMeasure your motor output shaft diameter with a caliper before ordering. The bore must match the shaft exactly for a secure press or set-screw fit. A 4 mm bore suits many micro-motor shafts; 5 mm and 6 mm are common on larger DC and stepper motors. If your shaft is between sizes, choose the smaller bore and ream to fit rather than using a larger bore with shims.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n\n    \u003cdetails\u003e\n      \u003csummary\u003eWill this gear mesh with my existing 0.5 mod plastic or metal gears?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eYes. Module is a standardized metric measurement — any two gears sharing the same module (0.5) and pressure angle (20°) will mesh correctly regardless of material. This brass spur gear will mesh with 0.5 mod plastic, aluminum, or steel gears of any tooth count.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n\n    \u003cdetails\u003e\n      \u003csummary\u003eHow strong is brass compared to steel or aluminum for this application?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eBrass sits between aluminum and mild steel in hardness. It handles moderate torque loads well and is significantly more durable than POM or nylon plastic gears. For high-torque or continuous-duty industrial applications, steel gears are recommended. For RC vehicles, robotics, and light automation — where low noise, corrosion resistance, and machinability matter — brass is a practical choice.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n\n    \u003cdetails\u003e\n      \u003csummary\u003eIs this gear corrosion-resistant for outdoor or humid environments?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eBrass offers inherent corrosion resistance superior to uncoated steel, making it suitable for indoor use and light outdoor exposure. For prolonged outdoor or marine environments, apply a light machine oil or grease to the gear teeth and bore to extend service life.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n\n    \u003cdetails\u003e\n      \u003csummary\u003eCan I use these gears in a 3D printer extruder or camera slider build?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eYes. The 0.5 mod \/ 20T geometry is commonly used in compact motorized mechanisms including extruder drives, camera pan\/tilt rigs, and linear sliders. Confirm that your mating gear or rack is also 0.5 module, and that the bore matches your stepper or servo motor shaft diameter.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n\n    \u003cdetails\u003e\n      \u003csummary\u003eWhat is the difference between ordering 1 PCS vs. 10 PCS — is the gear identical?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eYes, the gear specification is identical across all pack quantities. The only difference is the number of pieces per order. Bulk packs (5 PCS, 10 PCS) offer a lower per-unit cost and are ideal for prototyping, spare parts inventory, or multi-axis builds requiring several gears of the same size.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n\n    \u003cdetails\u003e\n      \u003csummary\u003eHow do I secure the gear to the motor shaft — set screw, press fit, or keyway?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eThe securing method depends on the specific variant's hub design. Most pinion gears in this size range use a set screw (grub screw) through the hub to clamp onto the shaft. If your variant includes a set screw hole, use an appropriately sized hex key to tighten against a flat on the motor shaft for best retention. Contact us to confirm the hub detail for your selected bore size.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n\n  \u003c\/div\u003e\n\n  \u003cdiv class=\"hdiy-cta\"\u003e\n    🛒 Select your \u003cstrong\u003ebore size and packing quantity\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 bore size — 4 mm, 5 mm, or 6 mm?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Measure your motor output shaft diameter with a caliper before ordering. The bore must match the shaft exactly for a secure press or set-screw fit. A 4 mm bore suits many micro-motor shafts; 5 mm and 6 mm are common on larger DC and stepper motors. If your shaft is between sizes, choose the smaller bore and ream to fit rather than using a larger bore with shims.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Will this gear mesh with my existing 0.5 mod plastic or metal gears?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Yes. Module is a standardized metric measurement — any two gears sharing the same module (0.5) and pressure angle (20°) will mesh correctly regardless of material. This brass spur gear will mesh with 0.5 mod plastic, aluminum, or steel gears of any tooth count.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"How strong is brass compared to steel or aluminum for this application?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Brass sits between aluminum and mild steel in hardness. It handles moderate torque loads well and is significantly more durable than POM or nylon plastic gears. For high-torque or continuous-duty industrial applications, steel gears are recommended. For RC vehicles, robotics, and light automation — where low noise, corrosion resistance, and machinability matter — brass is a practical choice.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Is this gear corrosion-resistant for outdoor or humid environments?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Brass offers inherent corrosion resistance superior to uncoated steel, making it suitable for indoor use and light outdoor exposure. For prolonged outdoor or marine environments, apply a light machine oil or grease to the gear teeth and bore to extend service life.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Can I use these gears in a 3D printer extruder or camera slider build?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Yes. The 0.5 mod \/ 20T geometry is commonly used in compact motorized mechanisms including extruder drives, camera pan\/tilt rigs, and linear sliders. Confirm that your mating gear or rack is also 0.5 module, and that the bore matches your stepper or servo motor shaft diameter.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What is the difference between ordering 1 PCS vs. 10 PCS — is the gear identical?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Yes, the gear specification is identical across all pack quantities. The only difference is the number of pieces per order. Bulk packs (5 PCS, 10 PCS) offer a lower per-unit cost and are ideal for prototyping, spare parts inventory, or multi-axis builds requiring several gears of the same size.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"How do I secure the gear to the motor shaft — set screw, press fit, or keyway?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"The securing method depends on the specific variant's hub design. Most pinion gears in this size range use a set screw (grub screw) through the hub to clamp onto the shaft. If your variant includes a set screw hole, use an appropriately sized hex key to tighten against a flat on the motor shaft for best retention. Contact us to confirm the hub detail for your selected bore size.\"\n      }\n    }\n  ]\n}\n\u003c\/script\u003e","brand":"HomeDIYer","offers":[{"title":"0.5 Mod 20T 【Bore 4mm】 \/ 1 PCS","offer_id":52442803732754,"sku":"AdaahGFCD04365x1","price":7.85,"currency_code":"USD","in_stock":true},{"title":"0.5 Mod 20T 【Bore 5mm】 \/ 1 PCS","offer_id":52442803765522,"sku":"AdaahGFCD04366x1","price":7.85,"currency_code":"USD","in_stock":true},{"title":"0.5 Mod 20T 【Bore 6mm】 \/ 1 PCS","offer_id":52442803798290,"sku":"AdaahGFCD04367x1","price":7.93,"currency_code":"USD","in_stock":true},{"title":"0.5 Mod 20T 【Bore 4mm】 \/ 2 PCS","offer_id":52442803831058,"sku":"AdaahGFCD04365x2","price":11.63,"currency_code":"USD","in_stock":true},{"title":"0.5 Mod 20T 【Bore 5mm】 \/ 2 PCS","offer_id":52442803863826,"sku":"AdaahGFCD04366x2","price":11.63,"currency_code":"USD","in_stock":true},{"title":"0.5 Mod 20T 【Bore 6mm】 \/ 2 PCS","offer_id":52442803896594,"sku":"AdaahGFCD04367x2","price":12.0,"currency_code":"USD","in_stock":true},{"title":"0.5 Mod 20T 【Bore 4mm】 \/ 5 PCS","offer_id":52442803929362,"sku":"AdaahGFCD04365x5","price":20.81,"currency_code":"USD","in_stock":true},{"title":"0.5 Mod 20T 【Bore 5mm】 \/ 5 PCS","offer_id":52442803962130,"sku":"AdaahGFCD04366x5","price":20.81,"currency_code":"USD","in_stock":true},{"title":"0.5 Mod 20T 【Bore 6mm】 \/ 5 PCS","offer_id":52442803994898,"sku":"AdaahGFCD04367x5","price":21.69,"currency_code":"USD","in_stock":true},{"title":"0.5 Mod 20T 【Bore 4mm】 \/ 10 PCS","offer_id":52442804027666,"sku":"AdaahGFCD04365x10","price":35.89,"currency_code":"USD","in_stock":true},{"title":"0.5 Mod 20T 【Bore 5mm】 \/ 10 PCS","offer_id":52442804060434,"sku":"AdaahGFCD04366x10","price":35.75,"currency_code":"USD","in_stock":true},{"title":"0.5 Mod 20T 【Bore 6mm】 \/ 10 PCS","offer_id":52442804093202,"sku":"AdaahGFCD04367x10","price":37.39,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0884\/8936\/1682\/files\/Picture7of10_4373f838-ef30-4601-8abd-cc66ac76c8d8.jpg?v=1783596339","url":"https:\/\/homediyer.com\/products\/0-5-mod-brass-pinion-spur-gear-20t-bore-4-5-6mm","provider":"HomeDIYer","version":"1.0","type":"link"}