Split lock washers, inch (ASME B18.21.1): regular and high-collar spring washer ID, OD, thickness, width, #2 to 2 in — dimension sheet Source: Xem Studio, https://xemstudio.com/objects/split-lock-washers-inch-asme-b18-21-1/ (sheet CC BY 4.0) Basis: AFT Fasteners' regular / high-alloy table (ASME B18.21.1-1999) checked against the same table on a Tanner Bolt / CDE PDF, plus the same PDF family's high-collar sheet (ASME B18.21.1-2009); numbers only Catalog version: 2026-10-20 Sizes: see table below - Inches (OD also in mm). Regular (and 'high-alloy', which AFT and the CDE sheet say is dimensionally identical): nominal size, inside diameter min and max, outside diameter max, minimum mean section thickness (T + t) / 2, minimum section width W. AFT and the CDE PDF give identical numbers for every regular row (#2 to 2 in). - Column reading: both PDFs print a leading decimal that equals the nominal size, then two inside-diameter values and the OD. AFT lists the pair as min then max; the CDE sheet lists it larger-first with its own labels garbled, so the smaller of the pair is shown as ID min and the larger as ID max. The last two columns of each row are thickness and width: for regular washers they are 0.062 and 0.109 for 1/4 in (thickness first). - High collar (CDE sheet, ASME B18.21.1-2009, #4 to 1-1/2): the sheet's column headers are garbled in the extracted text. Its last two numbers are shown as width W and thickness (T + t) / 2 because the radial width of a washer cannot exceed (OD − ID min) / 2, and for 1/4 in that is 0.0555 in, which fits 0.047 but not 0.078. Check this table against the standard before relying on it. Heavy and extra-duty split washers (a distributor sheet prints them) are not tabulated here. - Not drawn: a split lock washer is a helix whose free height is not a column in any table read, so there is no honest solid; a flat ring would misstate it. Companion pages: tooth lock washers (tooth-lock-washers-inch-asme-b18-21-1), DIN 127 (spring-lock-washers-din-127-b) and Nord-Lock wedge washers. McMaster-Carr sells lock washers with per-part STEP; linked, not copied. type size nominal (in) ID min (in) ID max (in) OD max (in) width W min (in) mean thickness (T+t)/2 min (in) OD max (mm) regular #2 0.086 0.088 0.094 0.172 0.035 0.020 4.37 regular #3 0.099 0.101 0.107 0.195 0.040 0.025 4.95 regular #4 0.112 0.114 0.120 0.209 0.040 0.025 5.31 regular #5 0.125 0.127 0.133 0.236 0.047 0.031 5.99 regular #6 0.138 0.141 0.148 0.250 0.047 0.031 6.35 regular #8 0.164 0.167 0.174 0.293 0.055 0.040 7.44 regular #10 0.19 0.193 0.200 0.334 0.062 0.047 8.48 regular #12 0.216 0.220 0.227 0.377 0.070 0.056 9.58 regular 1/4 0.25 0.252 0.260 0.487 0.109 0.062 12.37 regular 5/16 0.312 0.314 0.322 0.583 0.125 0.078 14.81 regular 3/8 0.375 0.377 0.385 0.680 0.141 0.094 17.27 regular 7/16 0.438 0.440 0.450 0.776 0.156 0.109 19.71 regular 1/2 0.5 0.502 0.512 0.869 0.171 0.125 22.07 regular 9/16 0.562 0.564 0.574 0.965 0.188 0.141 24.51 regular 5/8 0.625 0.628 0.641 1.073 0.203 0.156 27.25 regular 3/4 0.75 0.753 0.766 1.265 0.234 0.188 32.13 regular 7/8 0.875 0.878 0.894 1.459 0.266 0.219 37.06 regular 1 1. 1.003 1.024 1.656 0.297 0.250 42.06 regular 1-1/8 1.125 1.129 1.153 1.847 0.328 0.281 46.91 regular 1-1/4 1.25 1.254 1.280 2.036 0.359 0.312 51.71 regular 1-3/8 1.375 1.379 1.408 2.219 0.391 0.344 56.36 regular 1-1/2 1.5 1.504 1.534 2.419 0.422 0.375 61.44 regular 1-3/4 1.75 1.758 1.789 2.679 0.424 0.389 68.05 regular 2 2. 2.008 2.039 2.936 0.427 0.422 74.57 high collar #4 0.112 0.114 0.120 0.173 0.022 0.022 4.39 high collar #6 0.138 0.141 0.148 0.216 0.030 0.030 5.49 high collar #8 0.164 0.167 0.174 0.267 0.042 0.047 6.78 high collar #10 0.19 0.193 0.200 0.294 0.042 0.047 7.47 high collar 1/4 0.25 0.252 0.260 0.363 0.047 0.078 9.22 high collar 5/16 0.3125 0.314 0.322 0.457 0.062 0.093 11.61 high collar 3/8 0.375 0.377 0.385 0.550 0.076 0.125 13.97 high collar 7/16 0.4375 0.440 0.450 0.644 0.090 0.140 16.36 high collar 1/2 0.5 0.502 0.512 0.733 0.103 0.172 18.62 high collar 9/16 0.5625 0.564 0.574 0.819 0.116 0.187 20.80 high collar 5/8 0.625 0.628 0.641 0.917 0.125 0.203 23.29 high collar 3/4 0.75 0.753 0.766 1.105 0.154 0.218 28.07 high collar 7/8 0.875 0.878 0.894 1.291 0.182 0.234 32.79 high collar 1 1. 1.003 1.024 1.478 0.208 0.250 37.54 high collar 1-1/8 1.125 1.129 1.153 1.663 0.236 0.313 42.24 high collar 1-1/4 1.25 1.254 1.280 1.790 0.236 0.313 45.47 high collar 1-1/2 1.5 1.504 1.534 2.159 0.292 0.375 54.84 Files elsewhere (not hosted by Xem Studio; license as stated by the publisher): - AFT Fasteners: Regular and high-alloy split helical spring lock washers (ASME B18.21.1-1999), #2 to 2 in — web — Publisher's page; dimensions are facts — https://www.aftfasteners.com/regular-high-alloy-split-helical-spring-lockwashers/ - Tanner Bolt / CDE sheet (Shopify CDN): Split lock washers, regular and high-alloy, ASME B18.21.1-1999: ID, OD, thickness, width — web — Maker datasheet; numbers only — https://cdn2.shopify.com/s/files/1/0056/7856/3437/files/Washerssplitalloy.pdf - Tanner Bolt / CDE sheet (Shopify CDN): High-collar helical spring lock washers (ASME B18.21.1-2009), #4 to 1-1/2 — web — Maker datasheet; numbers only — https://cdn2.shopify.com/s/files/1/0056/7856/3437/files/Washershicollar.pdf - McMaster-Carr: Split lock washers (regular and high collar) (free STEP/IGES per part, for your own design use; no redistribution) — STEP, IGES, PDF — McMaster-Carr site terms: personal design use, no redistribution [verify license at link] — https://www.mcmaster.com/products/lock-washers/ No true-size file yet: the published figures do not fix the whole shape; a measured scan is planned. API: https://xemstudio.com/api/geometry?object=split-lock-washers-inch-asme-b18-21-1