{"product_id":"lmuu-op-open-linear-bearings-optical-shafts","title":"LM10UU-OP ~ LM60UU-OP Open Linear Bearings Motion Linear Bearing Optical Shafts","description":"\u003cdiv class=\"hdiy-desc\"\u003e\n\n  \u003cdiv class=\"hdiy-overview\"\u003e\n    \u003ch2\u003eOpen Linear Bearings LM10UU-OP to LM60UU-OP — Smooth, Precise Motion on Optical Shafts\u003c\/h2\u003e\n    \u003cp\u003eWhen your CNC router, 3D printer, or linear actuator demands consistent, low-friction travel, a mismatched or worn bearing becomes the weakest link in your build. These open-type LMxUU-OP linear bearings are engineered for makers, machine builders, and automation engineers who need reliable linear motion without the bulk of a closed-type housing.\u003c\/p\u003e\n    \u003cp\u003eEach bearing features a steel outer shell with precision-ground ball retainer and recirculating steel balls, available in ten shaft-diameter sizes ranging from 10 mm (LM10UU-OP) up to 60 mm (LM60UU-OP). The open-type (OP) slot design allows the bearing to be mounted on shafts that pass through a support bracket, reducing overall assembly height. Outer diameters span 19 mm to 90 mm; body lengths span 29 mm to 110 mm (approximately 0.75 in to 4.33 in).\u003c\/p\u003e\n    \u003cp\u003eTypical applications include CNC gantry axes and router Z-carriages requiring smooth linear bearing for optical shafts, RepRap and cartesian 3D printer X\/Y rod systems, pick-and-place robotic arm linear slides, and DIY laser cutter bed travel assemblies — all scenarios where an open linear bearing for CNC motion control delivers measurable positioning repeatability.\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 Designed for use with hardened and ground optical shafts (h6 or h7 tolerance). Match the bearing inner diameter to your shaft diameter exactly — LM10UU-OP fits Ø10 mm shafts, LM12UU-OP fits Ø12 mm, and so on up to LM60UU-OP for Ø60 mm shafts.\n  \u003c\/div\u003e\n\n  \u003ch2\u003e✅ Key Features of These Open Linear Bearings\u003c\/h2\u003e\n  \u003cdiv class=\"hdiy-features\"\u003e\n\n    \u003cdiv\u003e\n      \u003cdiv class=\"hdiy-icon\"\u003e🔓\u003c\/div\u003e\n      \u003cstrong\u003eOpen-Type Slot Design\u003c\/strong\u003e\n      \u003cp\u003eThe longitudinal open slot (OP) allows the bearing to clear mounting brackets and reduces assembly height — ideal for compact carriage designs where a closed bearing won't fit.\u003c\/p\u003e\n    \u003c\/div\u003e\n\n    \u003cdiv\u003e\n      \u003cdiv class=\"hdiy-icon\"\u003e🎯\u003c\/div\u003e\n      \u003cstrong\u003eRecirculating Ball Precision\u003c\/strong\u003e\n      \u003cp\u003eMultiple rows of recirculating steel balls distribute load evenly, delivering smooth, low-friction travel and consistent positioning accuracy across the full stroke length.\u003c\/p\u003e\n    \u003c\/div\u003e\n\n    \u003cdiv\u003e\n      \u003cdiv class=\"hdiy-icon\"\u003e📐\u003c\/div\u003e\n      \u003cstrong\u003e10-Size Range (Ø10 mm – Ø60 mm)\u003c\/strong\u003e\n      \u003cp\u003eTen shaft-diameter options from LM10UU-OP to LM60UU-OP cover the most common optical shaft sizes used in CNC, 3D printing, and industrial linear motion systems.\u003c\/p\u003e\n    \u003c\/div\u003e\n\n    \u003cdiv\u003e\n      \u003cdiv class=\"hdiy-icon\"\u003e🛡️\u003c\/div\u003e\n      \u003cstrong\u003eSteel Construction with Sealed Ends\u003c\/strong\u003e\n      \u003cp\u003eHardened steel outer race and precision ball retainer resist deformation under radial load. Rubber end seals on each side retain grease and block contamination from chips and dust.\u003c\/p\u003e\n    \u003c\/div\u003e\n\n    \u003cdiv\u003e\n      \u003cdiv class=\"hdiy-icon\"\u003e🔧\u003c\/div\u003e\n      \u003cstrong\u003eDrop-In Replacement Fit\u003c\/strong\u003e\n      \u003cp\u003eDimensional tolerances follow standard LM-OP series specifications, making these a direct drop-in replacement for worn bearings in existing CNC and automation equipment without re-machining housings.\u003c\/p\u003e\n    \u003c\/div\u003e\n\n    \u003cdiv\u003e\n      \u003cdiv class=\"hdiy-icon\"\u003e📦\u003c\/div\u003e\n      \u003cstrong\u003eAvailable in Single or Twin Packs\u003c\/strong\u003e\n      \u003cp\u003eOrder 1 pc for a single-axis test or 2 pcs to equip both sides of a gantry carriage in one purchase — select your packing quantity above.\u003c\/p\u003e\n    \u003c\/div\u003e\n\n  \u003c\/div\u003e\n\n  \u003ch2\u003e📐 Technical Specifications — Open Linear Bearings\u003c\/h2\u003e\n  \u003cdiv class=\"hdiy-table-wrap\"\u003e\n    \u003ctable\u003e\n      \u003ctbody\u003e\n        \u003ctr\u003e\n\u003cth\u003eBearing Series\u003c\/th\u003e\n\u003ctd\u003eLMxUU-OP (Open Type)\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eAvailable Types\u003c\/th\u003e\n\u003ctd\u003eLM10UU-OP, LM12UU-OP, LM16UU-OP, LM20UU-OP, LM25UU-OP, LM30UU-OP, LM35UU-OP, LM40UU-OP, LM50UU-OP, LM60UU-OP\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eShaft Diameter (ID)\u003c\/th\u003e\n\u003ctd\u003e10 \/ 12 \/ 16 \/ 20 \/ 25 \/ 30 \/ 35 \/ 40 \/ 50 \/ 60 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eOuter Diameter (OD)\u003c\/th\u003e\n\u003ctd\u003e19 \/ 21 \/ 28 \/ 32 \/ 40 \/ 45 \/ 52 \/ 60 \/ 80 \/ 90 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eBody Length\u003c\/th\u003e\n\u003ctd\u003e29 \/ 30 \/ 37 \/ 42 \/ 59 \/ 64 \/ 70 \/ 80 \/ 100 \/ 110 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eBearing Type\u003c\/th\u003e\n\u003ctd\u003eOpen-type recirculating ball linear bearing\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eMaterial\u003c\/th\u003e\n\u003ctd\u003eHardened steel outer race, steel ball retainer, rubber end seals\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eShaft Tolerance Fit\u003c\/th\u003e\n\u003ctd\u003eh6 \/ h7 hardened optical shaft recommended\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003eLubrication\u003c\/th\u003e\n\u003ctd\u003ePre-greased; re-lubricate with lithium grease as needed\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003cth\u003ePacking Quantity\u003c\/th\u003e\n\u003ctd\u003e1 pc or 2 pcs (select variant)\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\u003eHow do I choose the right size open linear bearing for my shaft?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eMatch the bearing's inner diameter (ID) to your shaft diameter exactly. For example, if your optical shaft is 12 mm in diameter, select the LM12UU-OP (12×21×30 mm). Using a bearing with a larger ID than your shaft will cause slop and positioning errors.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n\n    \u003cdetails\u003e\n      \u003csummary\u003eWhat is the difference between an open-type (OP) and a standard closed linear bearing?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eA standard LMxUU bearing has a fully enclosed cylindrical shell. The open-type (OP) variant has a longitudinal slot cut along the outer shell, allowing the bearing to be clamped into a split housing or to clear a mounting bracket. This reduces assembly height and makes it easier to install on shafts that are already fixed in place.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n\n    \u003cdetails\u003e\n      \u003csummary\u003eAre these bearings compatible with induction-hardened or chrome-plated shafts?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eThese bearings are designed for use with hardened and ground optical shafts (surface hardness HRC 58–64, h6 or h7 diameter tolerance). Induction-hardened shafts meeting these tolerances are compatible. Soft or un-hardened shafts will wear prematurely under the ball contact stress.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n\n    \u003cdetails\u003e\n      \u003csummary\u003eHow much radial load can these open linear bearings handle?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eDynamic load capacity varies by size — smaller sizes such as LM10UU-OP are rated for lighter carriage loads (typically 5–15 kgf dynamic), while larger sizes like LM40UU-OP and above handle significantly higher loads. For exact load ratings, refer to the standard LM-OP series datasheet for your chosen size, or contact us to confirm suitability for your application.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n\n    \u003cdetails\u003e\n      \u003csummary\u003eDo I need to add grease before installation?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eThe bearings are pre-greased at the factory. For most light-duty CNC and 3D printer applications, no additional lubrication is needed before first use. For heavier-duty or high-cycle applications, apply a small amount of lithium-based grease through the open slot before installation and re-lubricate periodically.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n\n    \u003cdetails\u003e\n      \u003csummary\u003eCan I use one bearing per axis, or do I need two?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eFor most linear axes, two bearings per shaft are recommended to prevent the carriage from rocking (moment load). A single bearing is sufficient only for very short travel distances or when the carriage is constrained by a second parallel shaft. Select the 2-pc packing quantity to equip both sides of a carriage in one order.\u003c\/p\u003e\u003c\/div\u003e\n    \u003c\/details\u003e\n\n    \u003cdetails\u003e\n      \u003csummary\u003eAre these a direct replacement for existing LMxUU-OP bearings in my machine?\u003c\/summary\u003e\n      \u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eYes. These bearings follow standard LM-OP series dimensional specifications (inner diameter, outer diameter, and body length), making them a direct drop-in replacement for worn or damaged bearings in CNC routers, 3D printers, laser cutters, and other equipment that uses the LMxUU-OP standard — no housing re-machining required.\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 type, size, and packing quantity 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 size open linear bearing for my shaft?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Match the bearing's inner diameter (ID) to your shaft diameter exactly. For example, if your optical shaft is 12 mm in diameter, select the LM12UU-OP (12x21x30 mm). Using a bearing with a larger ID than your shaft will cause slop and positioning errors.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What is the difference between an open-type (OP) and a standard closed linear bearing?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"A standard LMxUU bearing has a fully enclosed cylindrical shell. The open-type (OP) variant has a longitudinal slot cut along the outer shell, allowing the bearing to be clamped into a split housing or to clear a mounting bracket. This reduces assembly height and makes it easier to install on shafts that are already fixed in place.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Are these bearings compatible with induction-hardened or chrome-plated shafts?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"These bearings are designed for use with hardened and ground optical shafts (surface hardness HRC 58-64, h6 or h7 diameter tolerance). Induction-hardened shafts meeting these tolerances are compatible. Soft or un-hardened shafts will wear prematurely under the ball contact stress.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"How much radial load can these open linear bearings handle?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Dynamic load capacity varies by size. Smaller sizes such as LM10UU-OP are rated for lighter carriage loads (typically 5-15 kgf dynamic), while larger sizes like LM40UU-OP and above handle significantly higher loads. Contact us to confirm suitability for your specific application.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Do I need to add grease before installation?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"The bearings are pre-greased at the factory. For most light-duty CNC and 3D printer applications, no additional lubrication is needed before first use. For heavier-duty or high-cycle applications, apply a small amount of lithium-based grease through the open slot before installation and re-lubricate periodically.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Can I use one bearing per axis, or do I need two?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"For most linear axes, two bearings per shaft are recommended to prevent the carriage from rocking (moment load). A single bearing is sufficient only for very short travel distances or when the carriage is constrained by a second parallel shaft.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Are these a direct replacement for existing LMxUU-OP bearings in my machine?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Yes. These bearings follow standard LM-OP series dimensional specifications, making them a direct drop-in replacement for worn or damaged bearings in CNC routers, 3D printers, laser cutters, and other equipment that uses the LMxUU-OP standard — no housing re-machining required.\"\n      }\n    }\n  ]\n}\n\u003c\/script\u003e","brand":"HomeDIYer","offers":[{"title":"LM10UU-OP \/ 10x19x29mm \/ 1","offer_id":52448893960466,"sku":"DGYNYGLBZSJ074085x1","price":11.4,"currency_code":"USD","in_stock":true},{"title":"LM12UU-OP \/ 12x21x30mm \/ 1","offer_id":52448893993234,"sku":"DGYNYGLBZSJ074086x1","price":10.17,"currency_code":"USD","in_stock":true},{"title":"LM16UU-OP \/ 16x28x37mm \/ 1","offer_id":52448894026002,"sku":"DGYNYGLBZSJ074087x1","price":11.02,"currency_code":"USD","in_stock":true},{"title":"LM20UU-OP \/ 20x32x42mm \/ 1","offer_id":52448894058770,"sku":"DGYNYGLBZSJ074088x1","price":12.48,"currency_code":"USD","in_stock":true},{"title":"LM25UU-OP \/ 25x40x59mm \/ 1","offer_id":52448894091538,"sku":"DGYNYGLBZSJ074089x1","price":23.64,"currency_code":"USD","in_stock":true},{"title":"LM30UU-OP \/ 30x45x64mm \/ 1","offer_id":52448894124306,"sku":"DGYNYGLBZSJ074090x1","price":26.9,"currency_code":"USD","in_stock":true},{"title":"LM35UU-OP \/ 25x52x70mm \/ 1","offer_id":52448894157074,"sku":"DGYNYGLBZSJ074091x1","price":43.11,"currency_code":"USD","in_stock":true},{"title":"LM40UU-OP \/ 40x60x80mm \/ 1","offer_id":52448894189842,"sku":"DGYNYGLBZSJ074092x1","price":60.52,"currency_code":"USD","in_stock":true},{"title":"LM50UU-OP \/ 50x80x100mm \/ 1","offer_id":52448894222610,"sku":"DGYNYGLBZSJ074093x1","price":156.1,"currency_code":"USD","in_stock":true},{"title":"LM60UU-OP \/ 60x90x110mm \/ 1","offer_id":52448894255378,"sku":"DGYNYGLBZSJ074094x1","price":196.08,"currency_code":"USD","in_stock":true},{"title":"LM10UU-OP \/ 10x19x29mm \/ 2","offer_id":52448894288146,"sku":"DGYNYGLBZSJ074085x2","price":15.2,"currency_code":"USD","in_stock":true},{"title":"LM12UU-OP \/ 12x21x30mm \/ 2","offer_id":52448894320914,"sku":"DGYNYGLBZSJ074086x2","price":13.57,"currency_code":"USD","in_stock":true},{"title":"LM16UU-OP \/ 16x28x37mm \/ 2","offer_id":52448894353682,"sku":"DGYNYGLBZSJ074087x2","price":20.1,"currency_code":"USD","in_stock":true},{"title":"LM20UU-OP \/ 20x32x42mm \/ 2","offer_id":52448894386450,"sku":"DGYNYGLBZSJ074088x2","price":23.09,"currency_code":"USD","in_stock":true},{"title":"LM25UU-OP \/ 25x40x59mm \/ 2","offer_id":52448894419218,"sku":"DGYNYGLBZSJ074089x2","price":45.29,"currency_code":"USD","in_stock":true},{"title":"LM30UU-OP \/ 30x45x64mm \/ 2","offer_id":52448894451986,"sku":"DGYNYGLBZSJ074090x2","price":51.82,"currency_code":"USD","in_stock":true},{"title":"LM35UU-OP \/ 25x52x70mm \/ 2","offer_id":52448894484754,"sku":"DGYNYGLBZSJ074091x2","price":84.29,"currency_code":"USD","in_stock":true},{"title":"LM40UU-OP \/ 40x60x80mm \/ 2","offer_id":52448894517522,"sku":"DGYNYGLBZSJ074092x2","price":119.0,"currency_code":"USD","in_stock":true},{"title":"LM50UU-OP \/ 50x80x100mm \/ 2","offer_id":52448894550290,"sku":"DGYNYGLBZSJ074093x2","price":310.22,"currency_code":"USD","in_stock":true},{"title":"LM60UU-OP \/ 60x90x110mm \/ 2","offer_id":52448894583058,"sku":"DGYNYGLBZSJ074094x2","price":390.29,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0884\/8936\/1682\/files\/Main-01_de9527ac-e47a-4d56-b27b-4628822c58d8.jpg?v=1783686161","url":"https:\/\/homediyer.com\/products\/lmuu-op-open-linear-bearings-optical-shafts","provider":"HomeDIYer","version":"1.0","type":"link"}