{"product_id":"baby-lock-lower-knife-405910201a","title":"Baby Lock Lower Knife 405910201A","description":"\u003cdiv style=\"font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif; color: #4a4a4a; line-height: 1.6; font-size: 16px; max-width: 1000px; margin: 0 auto; padding: 15px;\"\u003e\n\u003cp style=\"font-size: 1rem; line-height: 1.6; color: #4a4a4a; margin-bottom: 20px;\"\u003eThis replacement lower knife, part number 405-9102-01A, fits a range of Baby Lock BL3, BL4, and BL5 series sergers plus the EF405 and EF405M, along with the Simplicity SL600, SL660, and SL700. The lower knife is the stationary blade that the upper knife cuts against as you serge. When its edge becomes dull or chipped, the trim turns ragged and the upper knife wears faster. A fresh lower knife restores a clean, precise cut.\u003c\/p\u003e\n\u003cp style=\"font-size: 1rem; line-height: 1.6; color: #4a4a4a; margin-bottom: 20px;\"\u003eThe lower knife lasts longer than the upper knife, but it does wear over time. Replace the lower knife only when its condition or cutting performance warrants it, and inspect the upper knife at the same time. This is an affordable part that helps keep an older serger performing like new. Confirm your model in the specifications below.\u003c\/p\u003e\n\u003ch3 style=\"font-weight: bold; font-size: 1.25rem; border-bottom: 2px solid #eaeaea; padding-bottom: 8px; margin-top: 30px; margin-bottom: 15px; color: #222;\"\u003eSpecifications\u003c\/h3\u003e\n\u003cdiv style=\"border: 1px solid #eaeaea; border-radius: 6px; overflow: hidden; margin-bottom: 25px; font-size: 0.95rem; line-height: 1.5;\"\u003e\n\u003cdiv style=\"display: flex; justify-content: space-between; padding: 12px 15px; background-color: #f8fafc; border-bottom: 1px solid #eaeaea; align-items: center; gap: 15px;\"\u003e\n\u003cspan style=\"font-weight: bold; color: #333; min-width: 150px;\"\u003ePart Number\u003c\/span\u003e \u003cspan style=\"color: #4a4a4a; text-align: right;\"\u003e405-9102-01A\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display: flex; justify-content: space-between; padding: 12px 15px; background-color: #ffffff; border-bottom: 1px solid #eaeaea; align-items: center; gap: 15px;\"\u003e\n\u003cspan style=\"font-weight: bold; color: #333; min-width: 150px;\"\u003ePart Type\u003c\/span\u003e \u003cspan style=\"color: #4a4a4a; text-align: right;\"\u003eSerger lower knife (blade)\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display: flex; justify-content: space-between; padding: 12px 15px; background-color: #f8fafc; border-bottom: 1px solid #eaeaea; align-items: center; gap: 15px;\"\u003e\n\u003cspan style=\"font-weight: bold; color: #333; min-width: 150px;\"\u003eCompatible Models\u003c\/span\u003e \u003cspan style=\"color: #4a4a4a; text-align: right;\"\u003eBaby Lock BL3-318, BL3-402, BL3-406, BL3-407, BL3-416, BL3-417, BL3-426, BL4-436, BL4-714, BL4-738, BL5280E, EF405, EF405M; Simplicity SL600, SL660, SL700\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display: flex; justify-content: space-between; padding: 12px 15px; background-color: #ffffff; border-bottom: 1px solid #eaeaea; align-items: center; gap: 15px;\"\u003e\n\u003cspan style=\"font-weight: bold; color: #333; min-width: 150px;\"\u003eMaterial\u003c\/span\u003e \u003cspan style=\"color: #4a4a4a; text-align: right;\"\u003eSteel\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display: flex; justify-content: space-between; padding: 12px 15px; background-color: #f8fafc; align-items: center; gap: 15px;\"\u003e\n\u003cspan style=\"font-weight: bold; color: #333; min-width: 150px;\"\u003eQuantity\u003c\/span\u003e \u003cspan style=\"color: #4a4a4a; text-align: right;\"\u003e1\u003c\/span\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003ch3 style=\"font-weight: bold; font-size: 1.25rem; border-bottom: 2px solid #eaeaea; padding-bottom: 8px; margin-top: 30px; margin-bottom: 15px; color: #222;\"\u003eInstallation Tips\u003c\/h3\u003e\n\u003cul style=\"line-height: 1.6; color: #4a4a4a; margin-bottom: 20px; padding-left: 20px; list-style-type: disc;\"\u003e\n\u003cli style=\"margin-bottom: 12px;\"\u003eUnplug the serger before accessing the cutting area.\u003c\/li\u003e\n\u003cli style=\"margin-bottom: 12px;\"\u003eConsult your exact model's manual before removing the fixed lower knife. Contact a qualified service technician if replacement or alignment is designated as a service procedure.\u003c\/li\u003e\n\u003cli style=\"margin-bottom: 12px;\"\u003eFollow the specified lower-blade height and alignment for your model; do not assume the same setting applies to every compatible serger.\u003c\/li\u003e\n\u003cli style=\"margin-bottom: 12px;\"\u003eAfter correct installation and alignment, turn the handwheel slowly by hand to check that the knives pass each other without interference.\u003c\/li\u003e\n\u003cli style=\"margin-bottom: 12px;\"\u003eTest on scrap fabric before sewing your project. If cutting remains poor, have the machine checked by a qualified service technician.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 style=\"font-weight: bold; font-size: 1.25rem; border-bottom: 2px solid #eaeaea; padding-bottom: 8px; margin-top: 30px; margin-bottom: 15px; color: #222;\"\u003eSigns It Is Time to Replace\u003c\/h3\u003e\n\u003cul style=\"line-height: 1.6; color: #4a4a4a; margin-bottom: 20px; padding-left: 20px; list-style-type: disc;\"\u003e\n\u003cli style=\"margin-bottom: 12px;\"\u003eFabric edges look chewed, frayed, or uneven instead of cleanly trimmed.\u003c\/li\u003e\n\u003cli style=\"margin-bottom: 12px;\"\u003eThreads catch or the fabric drags as it passes the knives.\u003c\/li\u003e\n\u003cli style=\"margin-bottom: 12px;\"\u003eThe blade has visible nicks, dull spots, or damage after sewing over a pin.\u003c\/li\u003e\n\u003cli style=\"margin-bottom: 12px;\"\u003eInspect both cutting edges and replace a worn or damaged blade as needed. The fixed lower blade generally lasts longer and does not automatically need replacement when the upper blade is changed.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp style=\"font-size: 1rem; line-height: 1.6; color: #4a4a4a; margin-bottom: 20px;\"\u003e\u003cem\u003eModel compatibility is listed from published cross-reference information. If your exact model is not listed, please contact our team before ordering so we can help confirm fit.\u003c\/em\u003e\u003c\/p\u003e\n\u003ch3 style=\"font-weight: bold; font-size: 1.25rem; border-bottom: 2px solid #eaeaea; padding-bottom: 8px; margin-top: 30px; margin-bottom: 15px; color: #222;\"\u003eWhy Buy From World Weidner?\u003c\/h3\u003e\n\u003cp style=\"font-size: 1rem; line-height: 1.6; color: #4a4a4a; margin-bottom: 20px;\"\u003eBuying this lower knife from World Weidner means getting a correctly identified replacement part from a team that stocks and services serger parts every day. We list the part number and compatible models up front, ship quickly from Oklahoma, and back every order with the perks below. If you are unsure about fit, our support team can help you check your model before you order.\u003c\/p\u003e\n\u003cul style=\"line-height: 1.6; color: #4a4a4a; margin-bottom: 20px; padding-left: 20px; list-style-type: disc;\"\u003e\n\u003cli style=\"margin-bottom: 12px;\"\u003e\n\u003cstrong\u003e60-Day Money-Back Guarantee:\u003c\/strong\u003e We offer a generous 60-day full satisfaction and money-back guarantee for risk-free shopping on your purchase.\u003ca href=\"\/pages\/returns-refunds\" style=\"color: #0d6efd; text-decoration: underline; margin-left: 2px;\" target=\"_blank\"\u003e*\u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli style=\"margin-bottom: 12px;\"\u003e\n\u003cstrong\u003eLow Free Shipping Threshold:\u003c\/strong\u003e Enjoy free shipping within the contiguous United States on all qualifying orders over our low minimum threshold.\u003c\/li\u003e\n\u003cli style=\"margin-bottom: 12px;\"\u003e\n\u003cstrong\u003eFast Order Delivery:\u003c\/strong\u003e Orders ship quickly from our central Oklahoma warehouse, usually arriving at your doorstep within 1 to 4 business days.\u003c\/li\u003e\n\u003cli style=\"margin-bottom: 12px;\"\u003e\n\u003cstrong\u003eLoyalty Rewards Program:\u003c\/strong\u003e Earn 5% back on every purchase online and in-store. These points can be saved up and redeemed for discounts on anything we carry.\u003c\/li\u003e\n\u003cli style=\"margin-bottom: 12px;\"\u003e\n\u003cstrong\u003eReferral Bonus Perks:\u003c\/strong\u003e Take advantage of our \"Give $10, Get $10\" program that rewards both you and a friend with coupons for future orders and accessories.\u003c\/li\u003e\n\u003cli style=\"margin-bottom: 12px;\"\u003e\n\u003cstrong\u003eInterest-Free Financing:\u003c\/strong\u003e We partner with popular payment platforms to offer flexible, interest-free installment payments at checkout so you can start creating today.\u003c\/li\u003e\n\u003cli style=\"margin-bottom: 12px;\"\u003e\n\u003cstrong\u003eIn-House Customer Support:\u003c\/strong\u003e Our dedicated, knowledgeable team, including factory-trained service technicians, is available by phone, live chat, or email to assist with part identification, model compatibility questions, installation guidance, and project troubleshooting.\u003c\/li\u003e\n\u003cli style=\"margin-bottom: 12px;\"\u003e\n\u003cstrong\u003eMassive Interactive Showroom:\u003c\/strong\u003e Check out our 18,000-square-foot physical Creative Center in Oklahoma City for hands-on product demos, direct support, and community classes.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n","brand":"Baby Lock","offers":[{"title":"Default Title","offer_id":42662055772206,"sku":"405910201A","price":4.98,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0554\/7920\/5934\/files\/Baby_Lock_Lower_Knife_405910201A.png?v=1789487977","url":"https:\/\/www.worldweidner.com\/products\/baby-lock-lower-knife-405910201a","provider":"World Weidner","version":"1.0","type":"link"}