{"product_id":"chihai-rigid-brass-hex-shaft-coupling-18-30mm","title":"CHIHAI Rigid Brass Hex Shaft Coupling, 2–8mm Bore, 18\/30mm Length","description":"\u003ch2\u003eOverview\u003c\/h2\u003e\u003cp\u003eThis \u003ca href=\"https:\/\/rcdrone.top\/collections\/gears-transmission-parts\"\u003erigid hex shaft coupling\u003c\/a\u003e connects a matching motor shaft to a suitable 12 mm hex wheel hub or mechanism. The brass body is available in 18 mm standard and 30 mm extended lengths. Select the bore diameter and length independently; only actual available combinations are offered.\u003c\/p\u003e\u003ch2\u003eFeatures\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eRigid brass construction with a hexagonal drive end.\u003c\/li\u003e\n\u003cli\u003eFive bore diameters in the 18 mm version and four in the 30 mm version.\u003c\/li\u003e\n\u003cli\u003eM 4 radial set-screw fixing references and an M 4 threaded hex-face reference.\u003c\/li\u003e\n\u003cli\u003eEach coupling includes two fixing set screws and one hex key.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eSpecifications\u003c\/h2\u003e\u003cdiv style=\"overflow-x:auto\"\u003e\u003ctable\u003e\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eProduct\u003c\/td\u003e\n\u003ctd\u003eRigid brass hex shaft coupling \/ wheel adapter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaterial\u003c\/td\u003e\n\u003ctd\u003eBrass; custom aluminum\/steel manufacturing offers are not included retail options\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLength choices\u003c\/td\u003e\n\u003ctd\u003e18 mm standard or 30 mm extended\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e18 mm bore choices\u003c\/td\u003e\n\u003ctd\u003e2, 3, 4, 6 or 8 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e30 mm bore choices\u003c\/td\u003e\n\u003ctd\u003e3, 4, 6 or 8 mm; no 2 mm extended option\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eHex dimensions\u003c\/td\u003e\n\u003ctd\u003e12 mm across flats; 13.75 mm across corners reference\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRound body diameter\u003c\/td\u003e\n\u003ctd\u003e11.5 mm reference\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRadial fixing\u003c\/td\u003e\n\u003ctd\u003eM 4 opposed\/through radial threaded-hole reference for set-screw fastening\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eHex-face thread\u003c\/td\u003e\n\u003ctd\u003eM 4 axial threaded hole reference; confirm mating fastener engagement\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePackage\u003c\/td\u003e\n\u003ctd\u003eOne selected coupling, two fixing set screws and one hex key\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNot included\u003c\/td\u003e\n\u003ctd\u003eMotor, wheel, gearbox and complete mechanism; no axial wheel bolt specified\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRatings\u003c\/td\u003e\n\u003ctd\u003eNo torque, speed, runout or bore tolerance rating specified\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\u003c\/div\u003e\u003ch2\u003eSize Selection\u003c\/h2\u003e\u003cdiv style=\"overflow-x:auto\"\u003e\u003ctable\u003e\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eBore diameter\u003c\/td\u003e\n\u003ctd\u003eAvailable lengths\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e2 mm\u003c\/td\u003e\n\u003ctd\u003e18 mm only\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e3 mm\u003c\/td\u003e\n\u003ctd\u003e18 mm or 30 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e4 mm\u003c\/td\u003e\n\u003ctd\u003e18 mm or 30 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e6 mm\u003c\/td\u003e\n\u003ctd\u003e18 mm or 30 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e8 mm\u003c\/td\u003e\n\u003ctd\u003e18 mm or 30 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\u003c\/div\u003e\u003cp\u003eThe bore must match the actual shaft. The 12 mm across-flat hex dimension is a fit reference, not a guarantee of compatibility with every hex wheel. Check hub depth, shaft engagement, axial screw access and surrounding clearances before assembly. The 30 mm version provides additional reach; usable shaft insertion depth is not specified.\u003c\/p\u003e\u003ch2\u003eInstallation\u003c\/h2\u003e\u003cp\u003eSlide the matching bore onto the shaft, align the hex end with the mating hub and tighten the fixing screws evenly. Verify the actual M 4 radial and axial thread positions against the dimensioned view. Use an appropriately sized mating fastener with adequate engagement; an axial wheel bolt is not listed as included.\u003c\/p\u003e\u003cp\u003eThis is a rigid adapter and does not compensate for shaft misalignment. Support external loads and check screw security before operation. Do not assume a torque, speed or precision rating that has not been specified.\u003c\/p\u003e\u003ch2\u003eApplications\u003c\/h2\u003e\u003cp\u003eSmall robot wheel drives, DC gear-motor prototypes and compact mechanisms requiring a matching 12 mm hex connection with a selected shaft bore.\u003c\/p\u003e\u003ch2\u003eWhat's Included\u003c\/h2\u003e\u003cp\u003eOne selected brass coupling, two fixing set screws and one hex key. Product photos showing multiple sizes illustrate alternatives and viewing angles, not a multi-coupling pack. Motor, wheel, gearbox and mounting assembly are not included.\u003c\/p\u003e\u003ch2\u003eFAQ\u003c\/h2\u003e\u003ch3\u003eIs a 2 mm bore available in the 30 mm length?\u003c\/h3\u003e\u003cp\u003eNo.The 2 mm bore is offered only in the 18 mm length; the extended version starts at 3 mm.\u003c\/p\u003e\u003ch3\u003eIs this a flexible shaft-to-shaft coupling?\u003c\/h3\u003e\u003cp\u003eNo.It is a rigid hex adapter with a selected shaft bore and threaded fixing references. Match the actual shaft and mating hub geometry.\u003c\/p\u003e\u003ch3\u003eDoes the package include the motor and wheel?\u003c\/h3\u003e\u003cp\u003eNo.It includes one coupling, two fixing set screws and one hex key.\u003c\/p\u003e\u003ch2\u003eVisual Details\u003c\/h2\u003e\u003cfigure\u003e\u003ca href=\"https:\/\/rcdrone.top\/cdn\/shop\/files\/local68-137-dimensions.webp?v=1792842902\" target=\"_blank\" rel=\"noopener\"\u003e\u003cimg src=\"https:\/\/rcdrone.top\/cdn\/shop\/files\/local68-137-dimensions.webp?v=1792842902\" alt=\"Hex coupling dimensional reference\" style=\"max-width:100%;height:auto\" loading=\"lazy\"\u003e\u003c\/a\u003e\u003cfigcaption\u003eHex coupling dimensional reference\u003c\/figcaption\u003e\u003c\/figure\u003e\u003cfigure\u003e\u003ca href=\"https:\/\/rcdrone.top\/cdn\/shop\/files\/local68-137-selection.webp?v=1792842906\" target=\"_blank\" rel=\"noopener\"\u003e\u003cimg src=\"https:\/\/rcdrone.top\/cdn\/shop\/files\/local68-137-selection.webp?v=1792842906\" alt=\"Actual bore and length combinations\" style=\"max-width:100%;height:auto\" loading=\"lazy\"\u003e\u003c\/a\u003e\u003cfigcaption\u003eActual bore and length combinations\u003c\/figcaption\u003e\u003c\/figure\u003e\u003cfigure\u003e\u003ca href=\"https:\/\/rcdrone.top\/cdn\/shop\/files\/local68-137-package.webp?v=1792842911\" target=\"_blank\" rel=\"noopener\"\u003e\u003cimg src=\"https:\/\/rcdrone.top\/cdn\/shop\/files\/local68-137-package.webp?v=1792842911\" alt=\"One coupling with fixing hardware\" style=\"max-width:100%;height:auto\" loading=\"lazy\"\u003e\u003c\/a\u003e\u003cfigcaption\u003eOne coupling with fixing hardware\u003c\/figcaption\u003e\u003c\/figure\u003e","brand":"CHIHAI MOTOR","offers":[{"title":"2 mm \/ 18 mm","offer_id":68127832572128,"sku":"HEXCOUPLING-68137-01","price":8.85,"currency_code":"USD","in_stock":true},{"title":"3 mm \/ 18 mm","offer_id":68127832604896,"sku":"HEXCOUPLING-68137-02","price":8.85,"currency_code":"USD","in_stock":true},{"title":"4 mm \/ 18 mm","offer_id":68127832637664,"sku":"HEXCOUPLING-68137-03","price":8.85,"currency_code":"USD","in_stock":true},{"title":"6 mm \/ 18 mm","offer_id":68127832670432,"sku":"HEXCOUPLING-68137-04","price":8.85,"currency_code":"USD","in_stock":true},{"title":"8 mm \/ 18 mm","offer_id":68127832703200,"sku":"HEXCOUPLING-68137-05","price":8.85,"currency_code":"USD","in_stock":true},{"title":"3 mm \/ 30 mm","offer_id":68127832735968,"sku":"HEXCOUPLING-68137-06","price":9.31,"currency_code":"USD","in_stock":true},{"title":"4 mm \/ 30 mm","offer_id":68127832768736,"sku":"HEXCOUPLING-68137-07","price":9.31,"currency_code":"USD","in_stock":true},{"title":"6 mm \/ 30 mm","offer_id":68127832801504,"sku":"HEXCOUPLING-68137-08","price":9.31,"currency_code":"USD","in_stock":true},{"title":"8 mm \/ 30 mm","offer_id":68127832834272,"sku":"HEXCOUPLING-68137-09","price":9.31,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0643\/3210\/3904\/files\/local68-137-g5.jpg?v=1792842916","url":"https:\/\/rcdrone.top\/nl\/products\/chihai-rigid-brass-hex-shaft-coupling-18-30mm","provider":"RCDrone","version":"1.0","type":"link"}