{"product_id":"mod-1-steel-spur-gear-15-tooth-bore-4-5-6-7-8mm-transmission-pinion-with-screw","title":"Mod 1 Steel Spur Gear 15 Tooth Bore 4\/5\/6\/7\/8mm Transmission Pinion with Screw","description":"\u003cdiv class=\"hdiy-desc\"\u003e\n\n  \u003cdiv class=\"hdiy-overview\"\u003e\n    \u003ch2\u003eMod 1 Steel Spur Gear 15T — Reliable Transmission Pinion for Precision Drive Systems\u003c\/h2\u003e\n    \u003cp\u003eWhen a slipping or undersized gear causes your drive system to lose torque or skip under load, the fix starts with the right pinion. This Mod 1 steel spur gear with 15 teeth is engineered for hobbyists, makers, and engineers who need a dependable transmission component for RC vehicles, CNC builds, robotics platforms, and custom mechanical assemblies.\u003c\/p\u003e\n    \u003cp\u003eEach gear is machined from carbon steel and features a Module 1 (Mod 1) tooth profile — the most widely used metric gear standard. The bore diameter ranges from 4 mm (0.157 in) to 8 mm (0.315 in), covering the most common motor shaft sizes. A set screw is included for secure shaft fixation without additional hardware. Gear outer diameter is typically 17 mm (0.67 in) based on the Mod 1 \/ 15T formula (OD = (T + 2) × Module).\u003c\/p\u003e\n    \u003cp\u003eTypical use cases include: replacing worn pinion gears in 1:10 scale RC cars and trucks, building compact Mod 1 spur gear transmission pinion assemblies for CNC axis drives, and integrating into robotics joint actuators where a standardized metric gear pitch is required for meshing with Mod 1 rack-and-pinion or larger spur gears.\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 all standard \u003cstrong\u003eModule 1 (Mod 1)\u003c\/strong\u003e spur gears and racks. Select bore size to match your motor or shaft diameter (4 \/ 5 \/ 6 \/ 6.35 \/ 7 \/ 8 mm).\n  \u003c\/div\u003e\n\n  \u003cdiv class=\"hdiy-features\"\u003e\n    \u003ch2\u003e✅ Key Features of These Mod 1 Steel 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\u003eModule 1 Standard Tooth Profile\u003c\/strong\u003e — Fully compatible with the international Mod 1 gear system, ensuring accurate meshing with any standard Mod 1 counterpart gear or rack.\n      \u003c\/li\u003e\n      \u003cli\u003e\n        \u003cspan class=\"hdiy-icon\"\u003e⚙️\u003c\/span\u003e\n        \u003cstrong\u003e15-Tooth Pinion Configuration\u003c\/strong\u003e — A low tooth count delivers higher gear reduction ratios when paired with larger driven gears, ideal for torque-focused drive applications.\n      \u003c\/li\u003e\n      \u003cli\u003e\n        \u003cspan class=\"hdiy-icon\"\u003e🛠️\u003c\/span\u003e\n        \u003cstrong\u003eMultiple Bore Sizes Available\u003c\/strong\u003e — Choose from 4 mm, 5 mm, 6 mm, 6.35 mm (1\/4 in), 7 mm, or 8 mm bore to match your specific motor shaft without adapters.\n      \u003c\/li\u003e\n      \u003cli\u003e\n        \u003cspan class=\"hdiy-icon\"\u003e🔐\u003c\/span\u003e\n        \u003cstrong\u003eIncluded Set Screw for Secure Fixing\u003c\/strong\u003e — Each gear ships with a grub\/set screw so you can lock the pinion firmly onto the shaft and prevent rotational slippage under load.\n      \u003c\/li\u003e\n      \u003cli\u003e\n        \u003cspan class=\"hdiy-icon\"\u003e🏗️\u003c\/span\u003e\n        \u003cstrong\u003eCarbon Steel Construction\u003c\/strong\u003e — Machined from carbon steel for the strength and wear resistance needed in continuous-duty transmission and drive train applications.\n      \u003c\/li\u003e\n      \u003cli\u003e\n        \u003cspan class=\"hdiy-icon\"\u003e📐\u003c\/span\u003e\n        \u003cstrong\u003eConsistent Machined Tolerances\u003c\/strong\u003e — Gear teeth and bore are machined to tight tolerances to minimize backlash and ensure smooth, quiet power transmission across the full speed range.\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 — Mod 1 Spur Gear Pinion\u003c\/h2\u003e\n    \u003ctable\u003e\n      \u003ctbody\u003e\n        \u003ctr\u003e\n\u003cth\u003eModule (Pitch)\u003c\/th\u003e\n\u003ctd\u003eMod 1 (1 mm\/tooth)\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eNumber of Teeth\u003c\/th\u003e\n\u003ctd\u003e15T\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eOuter Diameter\u003c\/th\u003e\n\u003ctd\u003eApprox. 17 mm (0.67 in)\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eBore Diameter\u003c\/th\u003e\n\u003ctd\u003e4 \/ 5 \/ 6 \/ 6.35 \/ 7 \/ 8 mm (see variant options)\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eGear Width (Face 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\u003eCarbon Steel\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eFinish \/ Coating\u003c\/th\u003e\n\u003ctd\u003eSee variant options\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\u003eShaft Fixing Method\u003c\/th\u003e\n\u003ctd\u003eSet screw (included)\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eCompatible Gear Module\u003c\/th\u003e\n\u003ctd\u003eMod 1 only\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eTypical Application\u003c\/th\u003e\n\u003ctd\u003eRC vehicles, CNC drives, robotics, DIY transmissions\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eWeight\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\u003eWhat does \"Mod 1\" mean and will this gear mesh with my existing gears?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003e\"Mod 1\" (Module 1) is a metric gear standard where the module equals 1 mm per tooth. This gear will mesh correctly with any other Mod 1 spur gear or Mod 1 rack, regardless of tooth count, as long as the pressure angle is also 20°. It will NOT mesh with Mod 0.5, Mod 0.8, Mod 1.5, or imperial pitch gears.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n\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\u003cp\u003eMeasure your motor or drive shaft diameter with a caliper. Select the bore that matches exactly — for example, choose 6.35 mm if your shaft is 1\/4 inch (a common size on brushed DC motors). A bore that is too large will cause wobble even with the set screw tightened.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n\n    \u003cdetails\u003e\n      \u003csummary\u003eIs the set screw included, and what tool do I need to tighten it?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eYes, a set screw (grub screw) is included with each gear. You will need a hex key (Allen key) to tighten it — the exact size depends on the screw supplied, typically M2 or M2.5. We recommend applying a small amount of thread-locking compound for high-vibration applications.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n\n    \u003cdetails\u003e\n      \u003csummary\u003eHow strong is this gear — can it handle continuous load in a drivetrain?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eThe gear is machined from carbon steel, which provides good tensile strength and wear resistance for moderate-duty continuous operation. It is suitable for RC vehicle drivetrains, light CNC axis drives, and robotics joints. For very high-torque or high-RPM industrial applications, consult the load rating of your specific assembly.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n\n    \u003cdetails\u003e\n      \u003csummary\u003eIs this gear corrosion-resistant? Can I use it outdoors or in damp environments?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eCarbon steel has limited natural corrosion resistance. For outdoor or damp environments, we recommend applying a light machine oil or grease to the gear teeth and bore area. If corrosion resistance is a primary requirement, consider a stainless steel or brass gear alternative.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n\n    \u003cdetails\u003e\n      \u003csummary\u003eWhat gear ratio will I get when pairing this 15T pinion with a larger spur gear?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eThe gear ratio equals the number of teeth on the driven (larger) gear divided by 15. For example: pairing with a 45T gear gives a 3:1 reduction ratio, meaning the output shaft turns at one-third the speed of the input shaft with three times the torque. Use this formula to design your target drive ratio.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n\n    \u003cdetails\u003e\n      \u003csummary\u003eCan I use this pinion in a 3D printer or CNC machine extruder drive?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eYes — Mod 1 gears are commonly used in CNC machine axis drives and some extruder gear train designs. Verify that your existing driven gear is also Mod 1 and that the bore matches your stepper motor shaft (typically 5 mm for NEMA 17 motors). The 6.35 mm bore variant suits NEMA 23 motors with 1\/4-inch shafts.\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\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\": \"What does \\\"Mod 1\\\" mean and will this gear mesh with my existing gears?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Mod 1 (Module 1) is a metric gear standard where the module equals 1 mm per tooth. This gear meshes with any Mod 1 spur gear or rack with a 20° pressure angle. It will not mesh with Mod 0.5, Mod 0.8, Mod 1.5, or imperial pitch gears.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"How do I choose the right bore size for my motor shaft?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Measure your motor or drive shaft diameter with a caliper and select the matching bore. Choose 6.35 mm for 1\/4-inch shafts. A bore that is too large will cause wobble even with the set screw tightened.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Is the set screw included, and what tool do I need to tighten it?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Yes, a set screw is included with each gear. You will need a hex key (Allen key) to tighten it, typically M2 or M2.5 size. Thread-locking compound is recommended for high-vibration applications.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"How strong is this gear — can it handle continuous load in a drivetrain?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"The carbon steel construction provides good tensile strength and wear resistance for moderate-duty continuous operation, suitable for RC vehicle drivetrains, light CNC axis drives, and robotics joints.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Is this gear corrosion-resistant? Can I use it outdoors or in damp environments?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Carbon steel has limited natural corrosion resistance. Apply a light machine oil or grease for outdoor or damp use. For high corrosion resistance, consider a stainless steel or brass gear alternative.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What gear ratio will I get when pairing this 15T pinion with a larger spur gear?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Gear ratio = driven gear teeth ÷ 15. For example, a 45T driven gear gives a 3:1 reduction ratio — one-third the speed with three times the torque.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Can I use this pinion in a 3D printer or CNC machine extruder drive?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Yes. Verify your driven gear is also Mod 1 and the bore matches your motor shaft. The 5 mm bore suits NEMA 17 stepper motors; the 6.35 mm bore suits NEMA 23 motors with 1\/4-inch shafts.\"\n      }\n    }\n  ]\n}\n\u003c\/script\u003e","brand":"HomeDIYer","offers":[{"title":"1M-15T \/ 4mm","offer_id":52442120323346,"sku":"GLFBCQFGLBZSJ057386x1","price":9.15,"currency_code":"USD","in_stock":true},{"title":"1M-15T \/ 5mm","offer_id":52442120356114,"sku":"GLFBCQFGLBZSJ057387x1","price":9.15,"currency_code":"USD","in_stock":true},{"title":"1M-15T \/ 6mm","offer_id":52442120388882,"sku":"GLFBCQFGLBZSJ057388x1","price":9.15,"currency_code":"USD","in_stock":true},{"title":"1M-15T \/ 6.35mm","offer_id":52442120421650,"sku":"GLFBCQFGLBZSJ057389x1","price":9.36,"currency_code":"USD","in_stock":true},{"title":"1M-15T \/ 7mm","offer_id":52442120454418,"sku":"GLFBCQFGLBZSJ057390x1","price":9.15,"currency_code":"USD","in_stock":true},{"title":"1M-15T \/ 8mm","offer_id":52442120487186,"sku":"GLFBCQFGLBZSJ057391x1","price":10.17,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0884\/8936\/1682\/files\/Main-01_ef9f743f-4290-4159-84e8-4315cc448bb7.jpg?v=1783408282","url":"https:\/\/homediyer.com\/products\/mod-1-steel-spur-gear-15-tooth-bore-4-5-6-7-8mm-transmission-pinion-with-screw","provider":"HomeDIYer","version":"1.0","type":"link"}