{"$schema":"nativecad-dfm-pack/1","id":"tooling","title":"Tooling - fixture plates, jigs, workholding, gauges","sector":"tooling","version":"2026-09-03","summary":"Grid fixture plates, 3-2-1 locating, clamping, vise soft jaws, 1-2-3/2-4-6 blocks, drill jigs and bushings, go/no-go gauges, 3D-printed jigs, inspection and assembly fixtures, plus the materials, tolerances and tests a job-shop fixture is held to.","aliases":["fixture","jig","fixture plate","tooling plate","workholding","soft jaws","vise jaws","drill jig","gauge","go no-go","1-2-3 block","locating pin","clamp","modular fixture"],"crossSector":false,"size":"full","sources":[{"id":"carr-lane-handbook","title":"Carr Lane Manufacturing Co. — Jig and Fixture Handbook / Workholding Components Catalog","url":"https://www.carrlane.com/","accessed":"2026-09-03"},{"id":"mitee-bite-fixturing-guide","title":"Mitee-Bite Products — Fixturing Systems Catalog and Design Guide (dowel/tapped grid plates)","url":"https://www.miteebite.com/","accessed":"2026-09-03"},{"id":"renishaw-fixturing","title":"Renishaw — Modular Fixturing Systems (grid plate hole layout)","url":"https://www.renishaw.com/en/fixturing-systems--6015","accessed":"2026-09-03"},{"id":"kurt-workholding","title":"Kurt Workholding — Precision Vise Drawings and Specifications (DX6/D688 series)","url":"https://www.kurtworkholding.com/","accessed":"2026-09-03"},{"id":"mcmaster-123-block","title":"McMaster-Carr — Precision Ground 1-2-3 Blocks, dimensional drawing","url":"https://www.mcmaster.com/1-2-3-blocks/","accessed":"2026-09-03"},{"id":"iso-8977","title":"ISO 8977:2018 Drill jigs and fixtures — Bushes","url":"https://www.iso.org/standard/71512.html","accessed":"2026-09-03"},{"id":"ansi-b94-33","title":"ANSI/ASME B94.33-1974 (R2015) Drill Jig Bushings","url":"https://www.asme.org/codes-standards/find-codes-standards/b94-33-drill-jig-bushings","accessed":"2026-09-03"},{"id":"iso-1938","title":"ISO 1938-1:2015 Geometrical product specifications — Plain limit gauges — Part 1: Gauges for workpieces with size tolerances","url":"https://www.iso.org/standard/61529.html","accessed":"2026-09-03"},{"id":"asme-b89-1-6","title":"ASME B89.1.6-2002 (R2020) Measurement of Plain Internal and External Diameters","url":"https://www.asme.org/codes-standards/find-codes-standards/b89-1-6-measurement-plain-internal-external-diameters","accessed":"2026-09-03"},{"id":"iso-286","title":"ISO 286-1:2010 ISO code system for tolerances on linear sizes","url":"https://www.iso.org/standard/45123.html","accessed":"2026-09-03"},{"id":"iso-230-2","title":"ISO 230-2:2014 Test code for machine tools — Part 2: Determination of accuracy and repeatability of positioning","url":"https://www.iso.org/standard/62233.html","accessed":"2026-09-03"},{"id":"mic6-datasheet","title":"Cast aluminium tooling plate (MIC-6) technical data sheet — flatness, stress-relief and composition","accessed":"2026-09-03","note":"Manufacturer datasheet, exact vendor URL unconfirmed at time of writing"},{"id":"formlabs-jig-fixture","title":"Formlabs — 3D Printing Jigs, Fixtures and Gauges Design Guide","url":"https://formlabs.com/blog/3d-printed-jigs-fixtures/","accessed":"2026-09-03"},{"id":"markforged-composites","title":"Markforged — Design Guide for Composite (PA-CF/Onyx) Parts","url":"https://markforged.com/resources/learn/design-for-additive-manufacturing/materials-and-post-processing/materials-considerations/composites-material-considerations","accessed":"2026-09-03"}],"entries":[{"id":"fixture-grid-pitch","kind":"dimension","tier":1,"title":"Modular fixture-plate grid pitch","summary":"Modular tooling plates (Mitee-Bite, Renishaw style) carry a hole grid on 25 mm (1 in) or 50 mm pitch, dowelled and tapped, so any subplate or clamp lands on a repeatable station without new drilling.","applies":["fixture plate","tooling plate","grid plate","modular fixture"],"value":{"options":[25,50],"unit":"mm"},"basis":"Mitee-Bite and Renishaw catalog grid-plate series standardize on 25 mm/1 in metric-inch-compatible pitch, 50 mm on larger plates","sources":["mitee-bite-fixturing-guide","renishaw-fixturing"],"tags":["grid","pitch","modular","fixture-plate"]},{"id":"dowel-tapped-alternation","kind":"feature","tier":1,"title":"Alternating dowel / tapped grid hole pattern","summary":"Grid-plate stations alternate a precision dowel hole (dia6 H7 or dia8 H7, for locating) with a tapped hole (M6 or M8, for clamping) so every other node locates and every other node fastens - never both in one hole.","applies":["fixture plate","tooling plate","grid plate"],"value":{"table":[{"role":"locate","dia":6,"fit":"H7"},{"role":"clamp","thread":"M6"},{"role":"locate","dia":8,"fit":"H7"},{"role":"clamp","thread":"M8"}],"unit":"mm"},"basis":"Renishaw/Mitee-Bite grid plates checkerboard dowel and tapped stations so a subplate can be both located and bolted from the same grid","sources":["mitee-bite-fixturing-guide","renishaw-fixturing"],"tags":["dowel","tapped","grid","alternation"],"see":["hardware/dowel-pin-holes"]},{"id":"fixture-plate-thickness","kind":"dimension","tier":1,"title":"Fixture / tooling plate thickness","summary":"General-purpose fixture and grid plates run 12-25 mm thick: 12-16 mm for light fixtures and soft-jaw carriers, 20-25 mm where tapped holes must hold clamp preload and dowel holes must resist tipping under cutting load.","applies":["fixture plate","tooling plate","subplate"],"value":{"min":12,"max":25,"typical":20,"unit":"mm"},"basis":"Carr Lane and Mitee-Bite catalog plate thicknesses balance tapped-hole engagement depth against added mass and cost","sources":["carr-lane-handbook","mitee-bite-fixturing-guide"],"tags":["plate","thickness"]},{"id":"mic6-flatness","kind":"tolerance","tier":1,"title":"MIC-6 cast tooling plate flatness","summary":"MIC-6 cast, stress-relieved aluminium tooling plate holds flatness within 0.15 mm over any 300 mm span as-cast, far tighter than rolled 6061 plate, which is why it is the default fixture-plate stock.","applies":["mic-6","tooling plate","fixture plate"],"value":{"max":0.15,"unit":"mm"},"basis":"Cast (not rolled) and stress-relieved before machining, so internal stress does not release and warp the plate after milling","sources":["mic6-datasheet"],"tags":["mic-6","flatness","tooling-plate"]},{"id":"subplate-tslot-width","kind":"dimension","tier":2,"title":"Sub-plate T-slot width to match vise/table","summary":"A fixture subplate that clamps into a vise or mill-table T-slot is machined to the table's own slot width - 14 mm, 16 mm or 18 mm are the common metric machine-table sizes - so a standard T-nut and stud fit without an adapter.","applies":["subplate","fixture plate","t-slot"],"value":{"options":[14,16,18],"unit":"mm"},"basis":"Common metric mill/machining-center table T-slot widths (ISO T-slot series)","sources":["carr-lane-handbook"],"tags":["t-slot","subplate","vise","table"]},{"id":"three-two-one-principle","kind":"rule","tier":1,"title":"3-2-1 locating principle","summary":"A rigid body is fully located with 6 point contacts distributed 3-2-1: three points define the primary (largest) datum plane, two more define a secondary plane perpendicular to it, and one more a tertiary plane - removing all 6 degrees of freedom with the minimum contact.","applies":["fixture","jig","locating scheme"],"basis":"Kinematic locating theory (6 DOF = 6 constraints), the foundation of every jig-and-fixture handbook locating scheme","sources":["carr-lane-handbook"],"tags":["3-2-1","locating","datum","kinematic"]},{"id":"locating-pin-pair","kind":"feature","tier":1,"title":"Round + diamond locating pin pair","summary":"A 2-pin location uses one full round pin plus one diamond (relieved) pin on the second hole: the diamond pin's narrow flats absorb the hole-to-hole distance tolerance so the part is not over-constrained and does not bind going onto the pins.","applies":["fixture","jig","locating pin"],"basis":"A second round pin over-constrains two-hole location against normal hole-position tolerance; a diamond pin removes the redundant width constraint while still fixing rotation","sources":["carr-lane-handbook"],"tags":["locating-pin","diamond-pin","round-pin"]},{"id":"locating-pin-fit-clearance","kind":"tolerance","tier":1,"title":"Locating pin fit: hole H7, pin g6, 0.02-0.05 mm clearance","summary":"A removable locating pin is toleranced hole H7 / pin g6, giving 0.02-0.05 mm diametral clearance - loose enough to load and unload the part by hand, tight enough to hold the 0.01-0.02 mm repeatability a fixture is built for.","applies":["fixture","jig","locating pin"],"value":{"min":0.02,"max":0.05,"unit":"mm"},"basis":"ISO 286 H7/g6 sliding fit class, the standard running fit for a hand-loaded locating pin","sources":["iso-286"],"tags":["h7","g6","clearance","locating-pin"],"see":["hardware/press-fit-pin-interference"]},{"id":"locating-accuracy","kind":"tolerance","tier":1,"title":"Fixture locating repeatability","summary":"A precision machining or inspection fixture locates a part to within 0.01-0.02 mm from load to load - the number the pin fit, the locator wear and the clamping sequence are all budgeted against.","applies":["fixture","jig"],"value":{"min":0.01,"max":0.02,"unit":"mm"},"basis":"Typical repeatability target for a CNC or CMM fixture, well inside the part's own dimensional tolerance","sources":["carr-lane-handbook"],"tags":["repeatability","locating","accuracy"]},{"id":"toggle-clamp-holding-force","kind":"fastener","tier":1,"title":"Toggle / cam / strap clamp holding force","summary":"Manual toggle, cam and strap clamps used in fixturing are rated 100-2500 N holding force depending on size - small vertical toggles at the low end, heavy horizontal-hold-down toggles and screw-actuated strap clamps at the high end.","applies":["toggle clamp","cam clamp","strap clamp","clamp"],"value":{"min":100,"max":2500,"unit":"N"},"basis":"Manufacturer catalog holding-force ratings across the common toggle-clamp size range","sources":["carr-lane-handbook"],"tags":["clamp","toggle-clamp","holding-force"]},{"id":"clamp-force-vs-cutting-force","kind":"rule","tier":1,"title":"Clamp force must exceed cutting force with margin","summary":"Total clamping force normal to a cutting load should be at least 2-3x the peak cutting force component that could lift or slide the part, to hold position through chatter and interrupted cuts, not just under steady load.","applies":["fixture","clamp","workholding"],"value":{"min":2,"max":3,"unit":"ratio"},"basis":"Standard workholding safety-factor rule of thumb against milling/drilling thrust and tangential force","sources":["carr-lane-handbook"],"tags":["clamp-force","cutting-force","safety-factor"]},{"id":"kurt-vise-jaw-width","kind":"dimension","tier":1,"title":"Kurt 6 in vise jaw width","summary":"The Kurt 6 in machinist vise (DX6/D688 class) has a 152 mm (6 in) jaw width, the most common CNC-mill vise size and the reference dimension every 6 in soft-jaw blank is machined to fit.","applies":["vise","kurt vise","soft jaws"],"value":{"value":152,"unit":"mm"},"basis":"Kurt catalog jaw width for the 6 in vise family","sources":["kurt-workholding"],"tags":["vise","kurt","jaw-width"]},{"id":"soft-jaw-blank","kind":"dimension","tier":1,"title":"Soft jaw blank size for a 6 in vise","summary":"A pair of soft jaws for a 6 in vise starts as two 150 x 50 x 25 mm blanks (6061 or 1018), bolted onto the vise's jaw plates and then machined in place to the part's own profile - including any dowel-pin slot for repeat setups.","applies":["soft jaws","vise jaws","vise"],"value":{"table":[{"dim":"length","mm":150},{"dim":"height","mm":50},{"dim":"thickness","mm":25}],"unit":"mm"},"basis":"Standard soft-jaw blank size matched to the Kurt 6 in vise jaw width","sources":["kurt-workholding"],"tags":["soft-jaws","blank","vise"]},{"id":"vise-jaw-bolt-pattern","kind":"fastener","tier":1,"title":"Soft jaw mounting bolt pattern (Kurt 6 in)","summary":"Kurt 6 in vise soft jaws bolt on with 3 x half-13 UNC cap screws on a 114.3 mm (4.5 in) bolt spacing - the standard hole pattern soft-jaw blanks are pre-drilled to.","applies":["soft jaws","vise jaws","kurt vise"],"value":{"table":[{"count":3,"thread":"1/2-13 UNC","spacing_mm":114.3}]},"basis":"Kurt catalog jaw-mounting hole pattern for the 6 in vise family","sources":["kurt-workholding"],"tags":["soft-jaws","bolt-pattern","kurt"]},{"id":"123-block-dims","kind":"dimension","tier":1,"title":"1-2-3 block dimensions","summary":"A precision 1-2-3 block measures 1 x 2 x 3 in (25.4 x 50.8 x 76.2 mm), ground square and parallel on all faces to within microns, used as a locating riser, angle reference or clamping spacer.","applies":["1-2-3 block","workholding","setup block"],"value":{"table":[{"dim":"x","mm":25.4},{"dim":"y","mm":50.8},{"dim":"z","mm":76.2}]},"basis":"Defining dimension of the 1-2-3 block: 1, 2 and 3 inches on a side","sources":["mcmaster-123-block"],"tags":["1-2-3-block","setup-block"]},{"id":"drill-bushing-types","kind":"fastener","tier":2,"title":"Drill bushing types P / H / L","summary":"Press-fit drill bushings (ISO 8977 / ANSI B94.33) come in three types: P (press-fit, permanent), H (headed, seats on the jig plate face) and L (liner, a permanent sleeve a renewable bushing presses into).","applies":["drill jig","drill bushing","jig bushing"],"value":{"options":["P","H","L"]},"basis":"ISO 8977 and ANSI B94.33 define the standard bushing type letters and their press-fit / renewable roles","sources":["iso-8977","ansi-b94-33"],"tags":["drill-bushing","jig","iso-8977"]},{"id":"jig-plate-thickness-rule","kind":"rule","tier":1,"title":"Drill jig plate thickness vs. drill diameter","summary":"A drill jig plate is made 1.5-2x the drill diameter thick under the bushing bore, enough to keep the bushing supported and the drill guided straight without the plate becoming needlessly heavy.","applies":["drill jig","jig plate"],"value":{"min":1.5,"max":2,"unit":"ratio"},"basis":"Standard drill-jig design rule balancing bushing support against jig weight and cost","sources":["carr-lane-handbook"],"tags":["jig-plate","thickness","drill-bushing"]},{"id":"go-nogo-plug-gauge","kind":"dimension","tier":2,"title":"Go / no-go plug gauge sizing","summary":"A go/no-go plug gauge is a 2-piece pair machined to the hole tolerance band directly: the GO member is cut to the minimum allowed hole diameter (must enter) and the NO-GO member to the maximum allowed diameter (must not enter).","applies":["gauge","go no-go","plug gauge"],"value":{"table":[{"member":"GO","size":"min allowed hole dia"},{"member":"NO-GO","size":"max allowed hole dia"}]},"basis":"Functional-gauging convention: GO = lower limit, NO-GO = upper limit of the toleranced feature","sources":["iso-1938"],"tags":["gauge","go-no-go","plug-gauge"]},{"id":"gauge-tolerance-iso1938","kind":"tolerance","tier":1,"title":"Gauge manufacturing tolerance (ISO 1938)","summary":"ISO 1938 sizes a go/no-go gauge's own manufacturing tolerance at roughly 10% of the part tolerance it inspects, split as gauge-maker tolerance plus wear allowance, so the gauge itself never consumes a meaningful share of the part's tolerance band.","applies":["gauge","go no-go","ring gauge","plug gauge"],"value":{"typical":10,"unit":"%"},"basis":"ISO 1938-1 gauge tolerance grades (GG/G-class) sized as a fraction of the workpiece tolerance","sources":["iso-1938"],"tags":["gauge","tolerance","iso-1938"]},{"id":"alignment-pin","kind":"fastener","tier":2,"title":"Assembly-jig alignment / press-fit guide pin","summary":"An assembly jig locates two mating parts with a press-fit alignment pin (H7 press side, g6/f7 slip side on the part being aligned) so parts stack onto the jig in one orientation before fasteners are driven.","applies":["assembly jig","alignment pin","press-fit guide"],"value":{"options":[4,6,8,10,12],"unit":"mm"},"basis":"Same H7 press-fit convention as a fixture dowel, applied to hold two workpieces in registration rather than a workpiece to a fixture","sources":["carr-lane-handbook"],"tags":["alignment-pin","assembly-jig","press-fit"],"see":["hardware/dowel-pin-holes"]},{"id":"fixture-tolerance-critical","kind":"tolerance","tier":1,"title":"Fixture tolerance on locating features","summary":"Locating features on a fixture or jig - pin holes, datum pads, bushing bores - are held to +/-0.01-0.02 mm; everything else on the same plate (mounting holes, clearance pockets, edges) can run at a much looser +/-0.1 mm.","applies":["fixture","jig","fixture plate"],"value":{"min":0.01,"max":0.02,"unit":"mm"},"basis":"Locating features drive the fixture's repeatability budget directly; non-critical features do not","sources":["carr-lane-handbook"],"tags":["tolerance","locating","critical"]},{"id":"material-6061-t6","kind":"material","tier":1,"title":"6061-T6 aluminium for fixture bodies and soft jaws","summary":"6061-T6 (yield approx 276 MPa, density 2.70 g/cm3) is the default fixture-body and soft-jaw material: machines cleanly, holds a tapped hole well, and is light enough for a fixture an operator lifts by hand.","applies":["fixture","soft jaws","fixture plate"],"value":{"table":[{"property":"yield","value":276,"unit":"MPa"},{"property":"density","value":2.7,"unit":"g/cm3"}]},"basis":"General-purpose 6061-T6 mechanical properties, the standard aluminium fixture-component alloy","sources":["carr-lane-handbook"],"tags":["6061","aluminium","material"]},{"id":"material-1018","kind":"material","tier":1,"title":"1018 mild steel for jaws, locators and jig plates","summary":"1018 cold-rolled steel (yield approx 370 MPa, density 7.87 g/cm3) is the default steel for soft jaws, locators and jig plates needing more wear resistance and stiffness than aluminium but no hardening - it also case-hardens well where a wear surface is added later.","applies":["soft jaws","jig plate","locator"],"value":{"table":[{"property":"yield","value":370,"unit":"MPa"},{"property":"density","value":7.87,"unit":"g/cm3"}]},"basis":"General-purpose 1018 mild steel mechanical properties","sources":["carr-lane-handbook"],"tags":["1018","steel","material"]},{"id":"material-mic6","kind":"material","tier":1,"title":"MIC-6 cast tooling plate","summary":"MIC-6 is a cast, stress-relieved 5-series-like aluminium tooling plate (density approx 2.70 g/cm3) sold pre-flattened to 0.15 mm/300 mm - the default stock for fixture and grid plates over rolled 6061 wherever flatness matters more than raw strength.","applies":["fixture plate","tooling plate","grid plate"],"value":{"table":[{"property":"density","value":2.7,"unit":"g/cm3"},{"property":"flatness","value":0.15,"unit":"mm/300mm"}]},"basis":"MIC-6 datasheet: cast and stress-relieved for flatness stability, not for peak strength","sources":["mic6-datasheet"],"tags":["mic-6","tooling-plate","material"]},{"id":"test-repeatability-iso230","kind":"test","tier":2,"title":"Fixture repeatability test (ISO 230-2 style)","summary":"Load and unload the part on the fixture 10 times, probing the same feature each cycle: position must repeat within +/-0.01 mm for the fixture to be accepted, the same statistical-repeatability method ISO 230-2 uses for machine-tool positioning.","applies":["fixture","jig"],"value":{"value":10,"unit":"cycles"},"basis":"ISO 230-2 repeatability methodology (multiple approaches, statistical spread) applied to a fixture instead of a machine axis","sources":["iso-230-2"],"tags":["test","repeatability","iso-230"]},{"id":"123-block-hole-pattern","kind":"feature","tier":2,"title":"1-2-3 block hole pattern","summary":"A standard 1-2-3 block carries 23 holes: a grid of dia9.5 mm (3/8 in) plain dowel/clearance holes plus 3/8-16 UNC tapped holes through both large faces, so the block clamps to a fixture or another block from either side.","applies":["1-2-3 block"],"value":{"table":[{"item":"total holes","value":23},{"item":"plain hole","dia_mm":9.5},{"item":"tapped hole","thread":"3/8-16 UNC"}]},"basis":"McMaster-Carr 1-2-3 block dimensional drawing hole callouts","sources":["mcmaster-123-block"],"tags":["1-2-3-block","hole-pattern"]},{"id":"rest-pad-button","kind":"feature","tier":2,"title":"Rest pads and locating buttons","summary":"A rest pad (flat, dia10-25 mm face) or locating button (a shouldered pin with a small flat or crowned top) gives a fixture a hardened, replaceable contact point instead of resting the part directly on soft fixture-body material, which would wear and lose repeatability.","applies":["fixture","jig","rest pad","button"],"value":{"min":10,"max":25,"unit":"mm"},"basis":"Replaceable hardened contact points isolate wear from the (soft) fixture body, per standard jig-and-fixture practice","sources":["carr-lane-handbook"],"tags":["rest-pad","button","locating"]},{"id":"toe-clamp","kind":"feature","tier":2,"title":"Toe clamp","summary":"A toe clamp bolts flat to the fixture base and pushes down at a shallow 5-15 degree inward angle on the low edge of a thin part, holding it without blocking the top face - the standard clamp for sheet or plate parts machined on the top surface.","applies":["clamp","toe clamp"],"basis":"Toe clamps hold by the part's edge specifically to leave the top face open for machining","sources":["carr-lane-handbook"],"tags":["toe-clamp","clamp"]},{"id":"strap-clamp","kind":"feature","tier":2,"title":"Strap clamp","summary":"A strap (bridge) clamp pivots on a stud and step block, with an M8-M12 screw driving the far end down onto the part - simple, cheap and adjustable for a wide range of part heights, at the cost of blocking part of the top face under the strap.","applies":["clamp","strap clamp"],"basis":"Strap clamps trade top-face access for low cost and adjustability across part height","sources":["carr-lane-handbook"],"tags":["strap-clamp","clamp"]},{"id":"cam-clamp","kind":"feature","tier":2,"title":"Cam clamp","summary":"A cam clamp uses an eccentric lobe on a lever to drive a plunger or strap down with a quick 90 degree twist, trading peak holding force for a faster load/unload cycle than a threaded strap or toggle clamp - common on high-mix manual fixtures.","applies":["clamp","cam clamp"],"basis":"Cam action trades holding force for cycle-time speed versus a screw-actuated clamp","sources":["carr-lane-handbook"],"tags":["cam-clamp","clamp"]},{"id":"edge-clamp","kind":"feature","tier":2,"title":"Edge clamp","summary":"An edge clamp bolts to the side of a fixture and drives a plunger horizontally, typically 2-5 mm of travel, into the part's edge - useful when both the top and bottom faces are needed for machining or inspection.","applies":["clamp","edge clamp"],"basis":"Horizontal clamping frees both large faces of a thin or flat part","sources":["carr-lane-handbook"],"tags":["edge-clamp","clamp"]},{"id":"vise-jaw-heights","kind":"dimension","tier":2,"title":"Vise jaw height range","summary":"Standard vise jaw heights run 38-63 mm (1.5-2.5 in) above the vise body, with soft jaws typically machined at the 50 mm (2 in) height - tall enough to grip common stock, short enough to clear the spindle on a short-Z mill.","applies":["vise","soft jaws","jaw height"],"value":{"min":38,"max":63,"typical":50,"unit":"mm"},"basis":"Common vise-jaw height range across catalog vise sizes","sources":["kurt-workholding"],"tags":["vise","jaw-height"]},{"id":"soft-jaw-dowel-slot","kind":"feature","tier":2,"title":"Soft jaw dowel slot for repeat setups","summary":"A soft jaw pair machined for a specific part carries a small dia6-8 mm dowel-pin slot below the part profile, so the jaws re-seat in the exact same position after being removed for a tool change or another job - restoring the machined profile's location, not just its shape.","applies":["soft jaws"],"value":{"min":6,"max":8,"unit":"mm"},"basis":"A witness dowel slot lets soft jaws be removed and reinstalled without re-machining or re-touching-off","sources":["kurt-workholding"],"tags":["soft-jaws","dowel-slot"]},{"id":"workstop","kind":"feature","tier":2,"title":"Workstop","summary":"A workstop is 1 or 2 fixed pins or a block a part is pushed against before clamping, setting one axis of position by contact rather than by a locating pin through a hole - used when the part has no hole to locate on, only an edge.","applies":["fixture","jig","workstop"],"basis":"Edge-contact location for parts with no locating hole available","sources":["carr-lane-handbook"],"tags":["workstop","locating"]},{"id":"parallels","kind":"dimension","tier":2,"title":"Precision parallels","summary":"Ground parallel bars raise a part off the vise base or fixture floor by a fixed, matched height (common pairs: 25, 38, 50, 63 mm) so a part clears the jaws or table while both faces stay accessible; a matched pair is flat and equal-height to within a few microns.","applies":["parallels","vise","setup"],"value":{"options":[25,38,50,63],"unit":"mm"},"basis":"Common ground-parallel height series used to raise stock in a vise","sources":["carr-lane-handbook"],"tags":["parallels","setup"]},{"id":"246-block-dims","kind":"dimension","tier":2,"title":"2-4-6 block dimensions","summary":"A 2-4-6 block measures 2 x 4 x 6 in (50.8 x 101.6 x 152.4 mm), the larger sibling of the 1-2-3 block, used the same way - as a ground riser, angle reference or clamping spacer - where more height or span is needed.","applies":["2-4-6 block","setup block"],"value":{"table":[{"dim":"x","mm":50.8},{"dim":"y","mm":101.6},{"dim":"z","mm":152.4}]},"basis":"Defining dimension of the 2-4-6 block: 2, 4 and 6 inches on a side","sources":["mcmaster-123-block"],"tags":["2-4-6-block","setup-block"]},{"id":"angle-plate","kind":"feature","tier":2,"title":"Angle plate","summary":"An angle plate is a precision-ground fixture with two faces at a fixed 90 degree (or adjustable) angle, used to hold a part vertically for side machining or to present an angled datum face square to the table.","applies":["angle plate","fixture"],"basis":"Standard fixturing accessory for presenting a machined face perpendicular to the table","sources":["carr-lane-handbook"],"tags":["angle-plate","fixture"]},{"id":"drill-bushing-od-by-drill","kind":"dimension","tier":2,"title":"Drill bushing OD/ID sizing by drill diameter","summary":"A press-fit drill bushing's bore (ID) is sized to the drill diameter plus a few microns of running clearance, and its OD steps up in standard increments (commonly +5 to +8 mm over ID) so a family of drill sizes shares a small set of stocked bushing OD/jig-hole sizes.","applies":["drill jig","drill bushing"],"value":{"table":[{"drill_mm":3,"bushing_od_mm":8},{"drill_mm":6,"bushing_od_mm":12},{"drill_mm":10,"bushing_od_mm":16},{"drill_mm":16,"bushing_od_mm":22}],"unit":"mm"},"basis":"ISO 8977 / ANSI B94.33 standard bushing OD series matched to common drill diameters","sources":["iso-8977","ansi-b94-33"],"tags":["drill-bushing","od","sizing"]},{"id":"chip-clearance-below-bushing","kind":"rule","tier":2,"title":"Chip clearance below a drill bushing","summary":"Leave 1-1.5x the drill diameter of open clearance between the bushing's bottom face and the part surface, so chips can evacuate and coolant can reach the cut instead of packing against the bushing.","applies":["drill jig","drill bushing"],"value":{"min":1,"max":1.5,"unit":"ratio"},"basis":"Standard drill-jig chip-clearance rule of thumb below a bushing","sources":["carr-lane-handbook"],"tags":["chip-clearance","drill-bushing"]},{"id":"printed-jig-material","kind":"material","tier":2,"title":"3D-printed jig materials: PETG and PA-CF","summary":"A 3D-printed jig or check fixture is printed in PETG for a cheap, tough, low-volume tool, or carbon-fibre-filled nylon (PA-CF) for a stiffer, more dimensionally stable jig that sees repeated handling and light clamping loads.","applies":["3d printed jig","printed fixture","gauge"],"basis":"PETG is the low-cost general-purpose FDM material; PA-CF trades print cost for stiffness and creep resistance in a working jig","sources":["formlabs-jig-fixture","markforged-composites"],"tags":["petg","pa-cf","3d-print","material"]},{"id":"printed-jig-wall","kind":"rule","tier":2,"title":"3D-printed jig wall thickness","summary":"Walls on a 3D-printed jig or fixture body run 3-5 mm thick - thin FDM shells flex under clamp load and lose the repeatability a jig exists to provide, so a printed jig is built noticeably heavier-walled than an equivalent injection-moulded part.","applies":["3d printed jig","printed fixture"],"value":{"min":3,"max":5,"unit":"mm"},"basis":"FDM/FFF layer adhesion and infill stiffness are well below moulded plastic, so a functional jig wall is oversized versus a cosmetic part wall","sources":["formlabs-jig-fixture"],"tags":["3d-print","wall-thickness"]},{"id":"printed-jig-insert","kind":"feature","tier":2,"title":"Heat-set inserts in printed jigs","summary":"A 3D-printed jig that is bolted to a machine, clamped repeatedly, or reused across jobs gets heat-set brass inserts at every fastener location rather than threading the print itself - printed threads strip within a handful of cycles under clamp load.","applies":["3d printed jig","printed fixture"],"basis":"Printed plastic threads have poor cyclic-load durability; a heat-set insert moves the thread into metal","sources":["formlabs-jig-fixture"],"tags":["heat-set-insert","3d-print"],"see":["hardware/heat-set-inserts-metric"]},{"id":"printed-jig-tolerance","kind":"tolerance","tier":2,"title":"3D-printed jig dimensional tolerance","summary":"A 3D-printed jig or fixture feature holds about +/-0.2 mm as-printed on FDM/FFF, enough for a locating slot or a clearance hole but not for a precision press or slip fit, which should be reamed or pinned with a metal insert instead.","applies":["3d printed jig","printed fixture"],"value":{"value":0.2,"unit":"mm"},"basis":"Typical FDM dimensional accuracy on a well-tuned printer/material combination","sources":["formlabs-jig-fixture"],"tags":["3d-print","tolerance"]},{"id":"printed-jig-z-load","kind":"rule","tier":2,"title":"Avoid load-bearing features printed in Z","summary":"Do not put a clamp screw boss, a snap feature or a locating pin bore that sees repeated load along the print's Z (layer) axis - FDM/FFF interlayer strength runs only about 50-70% of in-plane strength, so a Z-loaded feature delaminates well before an XY-oriented one fails.","applies":["3d printed jig","printed fixture"],"basis":"FDM interlayer bond strength is a fraction of in-plane strength; orient load-bearing jig features in XY","sources":["formlabs-jig-fixture"],"tags":["3d-print","z-axis","orientation"]},{"id":"cmm-fixture-pin","kind":"feature","tier":2,"title":"CMM fixture pins and datum spheres","summary":"A CMM inspection fixture locates the part the same way a machining fixture does (3-2-1, pin pair) but adds tooling balls or datum spheres at known fixture-frame coordinates, so the CMM software can auto-align the fixture's own coordinate system before probing the part.","applies":["cmm fixture","inspection fixture"],"basis":"A CMM fixture must self-register to the machine before the part datums mean anything, hence the added tooling-ball references","sources":["carr-lane-handbook"],"tags":["cmm","inspection-fixture","tooling-ball"]},{"id":"assembly-jig-press-fit-guide","kind":"feature","tier":2,"title":"Assembly jig press-fit guides","summary":"An assembly jig guides a press-fit bushing or bearing into a housing with a hardened guide bushing of its own (typically 10-20 mm long), coaxial with the housing bore, so the press ram's force runs straight down the axis instead of cocking the part.","applies":["assembly jig","press-fit guide"],"basis":"A guided press prevents cocking, the dominant failure mode of an unguided manual press-fit","sources":["carr-lane-handbook"],"tags":["assembly-jig","press-fit"]},{"id":"hardening-wear-pad","kind":"material","tier":2,"title":"A2/D2 tool steel wear pads and locators","summary":"Wear pads, hardened locating buttons and bushing liners are made from A2 or D2 tool steel, hardened to 58-62 HRC - a fixture surface that sees repeated part loading and unloading wears far slower at this hardness than at as-machined 1018 or 6061.","applies":["wear pad","locating button","fixture"],"value":{"min":58,"max":62,"unit":"ratio"},"basis":"A2/D2 tool steel through-hardened or case-hardened to a wear-resistant range on fixture contact surfaces","sources":["carr-lane-handbook"],"tags":["a2","d2","tool-steel","hardness","hrc"]},{"id":"1018-case-hardening","kind":"rule","tier":2,"title":"1018 locators are case-hardened, not through-hardened","summary":"1018 mild steel does not through-harden usefully; a 1018 locator or bushing liner that needs a wear surface is carburized (case-hardened) instead, giving a hard skin over a tough, machinable core rather than switching the whole part to tool steel.","applies":["locator","jig plate","1018"],"basis":"1018's low carbon content limits through-hardening response; carburizing adds surface carbon before quenching","sources":["carr-lane-handbook"],"tags":["1018","case-hardening","carburizing"]},{"id":"fixture-tolerance-noncritical","kind":"tolerance","tier":2,"title":"Fixture tolerance on non-critical features","summary":"Features on a fixture plate that do not touch the part or a locator - mounting-bolt clearance holes, lightening pockets, plate edges - are held to a loose +/-0.1 mm, since tightening them buys no repeatability and only adds machining time.","applies":["fixture","fixture plate"],"value":{"value":0.1,"unit":"mm"},"basis":"Tolerance should track function; non-locating fixture features carry no repeatability requirement","sources":["carr-lane-handbook"],"tags":["tolerance","non-critical"]},{"id":"clamp-material-uhmw","kind":"material","tier":2,"title":"HDPE/UHMW clamping pads for soft or finished parts","summary":"A clamp or locator face that would mark a finished, painted or soft workpiece is faced with a 3-6 mm HDPE or UHMW pad instead of bare metal - low friction, self-lubricating, and soft enough to cushion the contact without denting the part.","applies":["clamp","soft fixture","finished part"],"basis":"UHMW/HDPE contact pads protect a cosmetic or soft surface that direct metal-to-metal clamping would damage","sources":["carr-lane-handbook"],"tags":["uhmw","hdpe","clamp-pad","material"]},{"id":"subplate-material-5052","kind":"material","tier":2,"title":"5052 aluminium vs. MIC-6 for subplates","summary":"5052-H32 sheet is a cheaper, more available subplate stock than cast MIC-6 where the flatness spec is loose (a clamp riser, a spacer plate); MIC-6 is worth its premium only when the plate itself carries a locating or datum surface.","applies":["subplate","fixture plate"],"basis":"Rolled 5052 costs less than cast MIC-6 but does not match its as-cast flatness stability","sources":["mic6-datasheet"],"tags":["5052","mic-6","subplate"]},{"id":"delrin-fixture","kind":"material","tier":3,"title":"Delrin (acetal) for low-friction jig bushings and slides","summary":"Delrin (acetal/POM) is used up to about 90-100 C for low-load jig bushings, sliding gib strips and gauge bodies, trading much lower wear life under real clamping load for low friction and dimensional stability without added lubrication.","applies":["jig","gauge","bushing"],"basis":"Acetal's self-lubricating, low-friction, dimensionally stable properties suit light-duty sliding fixture components","sources":["carr-lane-handbook"],"tags":["delrin","acetal","pom","material"]},{"id":"test-clamp-force","kind":"test","tier":2,"title":"Clamp force verification test","summary":"Verify each clamp station meets its rated 100-2500 N holding force (measured with a load cell, or a torque-to-force calculation on the clamp screw) before the fixture is released to production - an under-torqued clamp is the top cause of a part shifting mid-cut.","applies":["fixture","clamp"],"basis":"Clamp force is the single largest fixture failure mode (part shift) and is cheap to verify directly","sources":["carr-lane-handbook"],"tags":["test","clamp-force"]},{"id":"test-gauge-rr","kind":"test","tier":2,"title":"Gauge repeatability and reproducibility (Gauge R&R)","summary":"A go/no-go or dial gauge used for production inspection is qualified with a Gauge R&R study; the combined repeatability + reproducibility variation should consume no more than about 10% of the part tolerance, or the gauge itself is masking real process variation.","applies":["gauge","inspection"],"value":{"max":10,"unit":"%"},"basis":"Standard measurement-systems-analysis (MSA) acceptance criterion for a production gauge","sources":["iso-1938"],"tags":["gauge-rr","msa","test"]},{"id":"test-flatness-check","kind":"test","tier":2,"title":"Fixture-plate flatness check","summary":"Check a fixture plate's flatness with a surface plate and dial indicator, or a straightedge and feeler gauge, against its 0.15 mm/300 mm rating before it enters service and periodically after - a plate that has silently warped degrades every fixture built on it.","applies":["fixture plate","tooling plate"],"basis":"Flatness is the one fixture-plate spec that degrades silently with age and abuse, so it needs a recurring check, not just an incoming one","sources":["mic6-datasheet"],"tags":["flatness","test","inspection"]},{"id":"standard-iso8977","kind":"standard","tier":2,"title":"ISO 8977 - drill jig bushes","summary":"ISO 8977 defines the standard press-fit and renewable drill-bushing types, their OD/ID series and tolerances - the reference every drill-jig bushing bore in this pack is sized against.","applies":["drill jig","drill bushing"],"basis":"Governing international standard for drill jig bushings","sources":["iso-8977"],"tags":["standard","iso-8977"]},{"id":"standard-ansi-b94-33","kind":"standard","tier":2,"title":"ANSI/ASME B94.33 - drill jig bushings","summary":"ANSI/ASME B94.33 is the US-inch counterpart to ISO 8977 for drill jig bushing types, dimensions and fits, still widely referenced on inch-based shop drawings.","applies":["drill jig","drill bushing"],"basis":"Governing US standard for drill jig bushings, parallel to ISO 8977","sources":["ansi-b94-33"],"tags":["standard","ansi-b94-33"]},{"id":"standard-iso1938","kind":"standard","tier":2,"title":"ISO 1938 - plain limit gauges","summary":"ISO 1938 defines plain limit (go/no-go) gauge design, gauge tolerance grades and wear allowances for inspecting toleranced hole and shaft sizes - the standard behind every plug and ring gauge entry in this pack.","applies":["gauge","go no-go"],"basis":"Governing standard for plain limit gauges","sources":["iso-1938"],"tags":["standard","iso-1938"]},{"id":"standard-iso230-2","kind":"standard","tier":2,"title":"ISO 230-2 - machine tool positioning accuracy and repeatability","summary":"ISO 230-2 defines the statistical method (repeated bidirectional approaches, standard deviation of position) for measuring positioning accuracy and repeatability on a machine axis - adopted here as the model for a fixture repeatability test.","applies":["fixture","test"],"basis":"Standard the fixture repeatability test in this pack borrows its methodology from","sources":["iso-230-2"],"tags":["standard","iso-230-2"]},{"id":"standard-asme-b89-1-6","kind":"standard","tier":3,"title":"ASME B89.1.6 - measurement of plain diameters","summary":"ASME B89.1.6 defines calibration and measurement practice for plain internal and external diameters, including the master discs and ring/plug gauges used to certify a shop's own go/no-go gauges.","applies":["gauge","calibration"],"basis":"Governing US standard for calibrating the diameter gauges this pack describes","sources":["asme-b89-1-6"],"tags":["standard","asme-b89-1-6"]},{"id":"standard-iso286","kind":"standard","tier":3,"title":"ISO 286 - ISO system of limits and fits","summary":"ISO 286 defines the hole-basis/shaft-basis tolerance grades (IT grades, letter classes like H7, g6) used throughout this pack for pin, bushing and dowel fits.","applies":["fit","tolerance","locating pin"],"basis":"Governing standard behind every H7/g6-style fit callout in this pack","sources":["iso-286"],"tags":["standard","iso-286"]},{"id":"ring-gauge","kind":"feature","tier":3,"title":"Ring gauge","summary":"A ring gauge is the 2-piece go/no-go pair for an external (shaft) diameter, the mirror of a plug gauge for a hole: GO ring slips over the maximum allowed shaft size, NO-GO stops at the minimum - used to check a fixture's own locating pin.","applies":["gauge","ring gauge"],"basis":"ISO 1938-class functional gauging for external diameters","sources":["iso-1938"],"tags":["ring-gauge","gauge"]},{"id":"feeler-gauge","kind":"dimension","tier":3,"title":"Feeler gauge for gap and clearance checks","summary":"A feeler gauge set (typically 0.05-1.0 mm blades) checks small, specific gaps in a fixture - clamp-to-part clearance, parallel-to-vise-body seating, shim thickness - by feel rather than a dial reading.","applies":["gauge","feeler gauge"],"value":{"min":0.05,"max":1,"unit":"mm"},"basis":"Standard feeler-gauge blade thickness range","sources":["carr-lane-handbook"],"tags":["feeler-gauge","gauge"]},{"id":"datum-sphere","kind":"feature","tier":3,"title":"Datum sphere / tooling ball","summary":"A datum sphere (tooling ball), typically 6-12.7 mm diameter, is a precision-ground steel or ceramic ball mounted at a known fixture-frame location, probed by a CMM to establish the fixture's coordinate system independent of the part it holds.","applies":["cmm fixture","inspection fixture","datum sphere"],"basis":"A sphere gives a CMM probe an unambiguous single point regardless of approach direction, unlike a flat pad or edge","sources":["carr-lane-handbook"],"tags":["datum-sphere","tooling-ball","cmm"]},{"id":"edm-laser-marking-reference","kind":"note","tier":3,"title":"EDM and laser marking reference features on fixtures","summary":"Fixtures for wire/sinker EDM or laser marking add a small reference flat, notch or datum hole so the downstream machine can register the part optically or electrically to the same origin the fixture used, keeping a multi-process part in one coordinate frame across machines.","applies":["edm","laser marking","fixture"],"basis":"Cross-process registration avoids re-establishing datums on a second machine","sources":["carr-lane-handbook"],"tags":["edm","laser-marking","reference"]},{"id":"modular-fixture-system","kind":"note","tier":3,"title":"Modular fixture systems","summary":"A modular fixture system (Renishaw, Mitee-Bite, System 3R style) builds a job-specific fixture from a catalog of grid plates, risers, clamps and locators rather than machining a one-off - faster to build and tear down, at some cost in stiffness versus a dedicated fixture.","applies":["modular fixture","fixture plate"],"basis":"Catalog components traded against dedicated-fixture stiffness and part-specific optimization","sources":["renishaw-fixturing","mitee-bite-fixturing-guide"],"tags":["modular-fixture","system-3r"]},{"id":"recipe-fixture-plate-dowel-tap-grid","kind":"recipe","tier":2,"title":"Recipe: fixture plate with alternating dowel/tapped grid","summary":"Build a 150x100x20 mm fixture plate with a 25 mm-pitch grid of alternating dia6 drill (locating) and M6 tapped (clamping) holes, two offset grids on one plate.","applies":["fixture plate","grid plate"],"basis":"Combines fixture-grid-pitch, dowel-tapped-alternation and fixture-plate-thickness into one buildable plate","sources":["mitee-bite-fixturing-guide","renishaw-fixturing"],"tags":["recipe","fixture-plate","grid"],"recipe":{"prompt":"Model a 150x100x20mm fixture plate with a 25mm grid of alternating dowel holes and M6 tapped holes","steps":[{"tool":"cad_box","args":{"dx":150,"dy":100,"dz":20},"note":"plate blank, 150x100x20mm 6061-T6"},{"tool":"cad_hole_pattern","args":{"of":"$0","type":"drill","diameter":6,"pattern":{"kind":"grid","origin":[25,25],"dx":50,"dy":50,"nx":3,"ny":2}},"note":"6 locating dowel holes, dia6, on the 25mm-offset grid columns x=25,75,125"},{"tool":"cad_hole_pattern","args":{"of":"$1","type":"tapped","size":"M6","depth":12,"pattern":{"kind":"grid","origin":[50,25],"dx":50,"dy":50,"nx":2,"ny":2}},"note":"4 M6 tapped clamp holes, blind 12mm (2xD), interleaved 25mm off the dowel columns at x=50,100"}],"expect":{"volume":295664.6,"faceCount":30,"watertight":true,"note":"measured 2026-09-19: agrees with the kernel on the CADSF-1630 corpus sweep — volume inside the 0.5% band and faceCount exact"}}},{"id":"recipe-soft-jaws","kind":"recipe","tier":2,"title":"Recipe: soft jaw blank with pocket and bolt counterbores","summary":"Build a 150x50x25 mm 6061 soft-jaw blank, cut a 100x20x10 mm workpiece pocket into the top face, and add two M8 counterbored mounting holes on the Kurt jaw bolt spacing.","applies":["soft jaws","vise jaws"],"basis":"Combines soft-jaw-blank, vise-jaw-bolt-pattern (scaled to M8 counterbore) and a boolean-cut pocket into one buildable jaw","sources":["kurt-workholding"],"tags":["recipe","soft-jaws","vise"],"recipe":{"prompt":"Model a 150x50x25mm soft jaw blank with a 100x20x10mm pocket and two M8 counterbored mounting holes","steps":[{"tool":"cad_box","args":{"dx":150,"dy":50,"dz":25},"note":"soft jaw blank, 150x50x25mm 6061-T6"},{"tool":"cad_box","args":{"dx":100,"dy":20,"dz":10,"origin":[25,15,15]},"note":"pocket tool, 100x20x10mm, cut from the top face down"},{"tool":"cad_boolean_subtract","args":{"of":"$0","tool":"$1"},"note":"subtract to cut the workpiece pocket"},{"tool":"cad_hole_pattern","args":{"of":"$2","type":"counterbore","size":"M8","pattern":{"kind":"linear","origin":[30,25],"step":[90,0],"count":2}},"note":"2 M8 counterbored mounting holes, 90mm apart"}],"expect":{"volume":165281.73,"faceCount":21,"watertight":true,"note":"measured 2026-09-19: representation change, not geometry: pinned while the boolean published a TESSELLATED B-rep (one planar face per triangle) and it now publishes an analytic one — faceCount 87 -> 21, volume identical to 0.003%: the M8 counterbore pattern is analytic again and the body is all-planar plus two counterbores"}}},{"id":"recipe-drill-jig","kind":"recipe","tier":2,"title":"Recipe: drill jig plate with bushing bores and locating pin holes","summary":"Build a 120x80x16 mm drill jig plate with two dia12 press-fit bushing bores on a 60 mm spacing plus a round and a diamond locating pin hole for the workpiece.","applies":["drill jig","jig plate"],"basis":"Combines jig-plate-thickness-rule, drill-bushing-od-by-drill and locating-pin-pair into one buildable jig plate","sources":["iso-8977","ansi-b94-33"],"tags":["recipe","drill-jig"],"recipe":{"prompt":"Model a 120x80x16mm drill jig plate with two press-fit bushing bores and a round + diamond locating pin hole pair","steps":[{"tool":"cad_box","args":{"dx":120,"dy":80,"dz":16},"note":"jig plate blank, 120x80x16mm 1018 steel"},{"tool":"cad_hole_pattern","args":{"of":"$0","type":"drill","diameter":12,"pattern":{"kind":"linear","origin":[30,40],"step":[60,0],"count":2}},"note":"2 press-fit bushing bores, dia12mm for a 6mm drill bushing OD, 60mm apart"},{"tool":"cad_drill_hole","args":{"of":"$1","type":"drill","diameter":8,"center":[15,15]},"note":"round locating pin hole, dia8 through"},{"tool":"cad_drill_hole","args":{"of":"$2","type":"drill","diameter":8,"center":[105,65]},"note":"diamond locating pin hole bore, dia8 through (the diamond relief is machined into the pin, not this hole)"}],"expect":{"volume":148372.39,"faceCount":14,"watertight":true,"note":"measured 2026-09-19: agrees with the kernel on the CADSF-1630 corpus sweep — volume inside the 0.5% band and faceCount exact"}}}]}