{"id":6549,"date":"2026-08-05T15:53:53","date_gmt":"2026-08-05T07:53:53","guid":{"rendered":"https:\/\/broachingmach.com\/?p=6549"},"modified":"2026-08-03T10:47:09","modified_gmt":"2026-08-03T02:47:09","slug":"transmission-gear-internal-spline-broaching","status":"publish","type":"post","link":"https:\/\/broachingmach.com\/en_ca\/transmission-gear-internal-spline-broaching\/","title":{"rendered":"Transmission Gear Internal Spline Broaching: Soft, Hard and Inspection Planning"},"content":{"rendered":"<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/broachingmach.com\/wp-content\/uploads\/2026\/07\/transmission-gear-internal-spline-broaching-hero.png\" alt=\"Conceptual transmission gear internal spline broaching application review\"><\/p><div id=\"ez-toc-container\" class=\"ez-toc-v2_0_86 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<div class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/div>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewbox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewbox=\"0 0 24 24\" version=\"1.2\" baseprofile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 eztoc-toggle-hide-by-default' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/broachingmach.com\/en_ca\/transmission-gear-internal-spline-broaching\/#Define_the_Exact_Gear_Spline_and_Manufacturing_Stage\" >Define the Exact Gear, Spline and Manufacturing Stage<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/broachingmach.com\/en_ca\/transmission-gear-internal-spline-broaching\/#Freeze_the_Soft-Broaching_Route\" >Freeze the Soft-Broaching Route<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/broachingmach.com\/en_ca\/transmission-gear-internal-spline-broaching\/#Decide_Whether_Hard_Broaching_Is_a_Finishing_Candidate\" >Decide Whether Hard Broaching Is a Finishing Candidate<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/broachingmach.com\/en_ca\/transmission-gear-internal-spline-broaching\/#Define_the_Spline_Datum_and_Protected-Zone_Map\" >Define the Spline, Datum and Protected-Zone Map<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/broachingmach.com\/en_ca\/transmission-gear-internal-spline-broaching\/#Select_the_Internal_Spline_Broach_Conditionally\" >Select the Internal Spline Broach Conditionally<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/broachingmach.com\/en_ca\/transmission-gear-internal-spline-broaching\/#Select_the_Machine_From_Force_Stroke_and_Process_Control\" >Select the Machine From Force, Stroke and Process Control<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/broachingmach.com\/en_ca\/transmission-gear-internal-spline-broaching\/#Build_the_Gear_Fixture_and_Pull-Broach_Alignment\" >Build the Gear Fixture and Pull-Broach Alignment<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/broachingmach.com\/en_ca\/transmission-gear-internal-spline-broaching\/#Control_Chips_Fluid_and_Tool_Condition\" >Control Chips, Fluid and Tool Condition<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/broachingmach.com\/en_ca\/transmission-gear-internal-spline-broaching\/#Inspect_the_Finished_Internal_Spline\" >Inspect the Finished Internal Spline<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/broachingmach.com\/en_ca\/transmission-gear-internal-spline-broaching\/#Sample-Test_and_Release_Plan\" >Sample-Test and Release Plan<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"https:\/\/broachingmach.com\/en_ca\/transmission-gear-internal-spline-broaching\/#Information_Needed_for_a_Transmission_Gear_Spline_Proposal\" >Information Needed for a Transmission Gear Spline Proposal<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-12\" href=\"https:\/\/broachingmach.com\/en_ca\/transmission-gear-internal-spline-broaching\/#Frequently_Asked_Questions\" >Frequently Asked Questions<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-13\" href=\"https:\/\/broachingmach.com\/en_ca\/transmission-gear-internal-spline-broaching\/#Should_a_transmission_gear_spline_be_broached_before_heat_treatment\" >Should a transmission gear spline be broached before heat treatment?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-14\" href=\"https:\/\/broachingmach.com\/en_ca\/transmission-gear-internal-spline-broaching\/#Can_hard_broaching_generate_the_full_spline\" >Can hard broaching generate the full spline?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-15\" href=\"https:\/\/broachingmach.com\/en_ca\/transmission-gear-internal-spline-broaching\/#Does_a_hard_gear_automatically_require_a_servo_broaching_machine\" >Does a hard gear automatically require a servo broaching machine?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-16\" href=\"https:\/\/broachingmach.com\/en_ca\/transmission-gear-internal-spline-broaching\/#Can_the_same_broach_run_every_gear_variant\" >Can the same broach run every gear variant?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-17\" href=\"https:\/\/broachingmach.com\/en_ca\/transmission-gear-internal-spline-broaching\/#How_is_an_internal_spline_inspected\" >How is an internal spline inspected?<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-18\" href=\"https:\/\/broachingmach.com\/en_ca\/transmission-gear-internal-spline-broaching\/#Final_Recommendation\" >Final Recommendation<\/a><\/li><\/ul><\/nav><\/div>\n\n<p><em>Engineering concept illustration of a transmission gear with a through internal spline under process review. It is not a customer part, delivered machine or dimensional drawing.<\/em><\/p>\n<p>An internal spline can connect a transmission gear to a shaft while maintaining rotational alignment and torque transfer. Broaching is a production candidate when the spline passes through the gear bore, the workpiece and tool can be guided on controlled datums, and the material, stock and machine load remain stable.<\/p>\n<p>The manufacturing stage changes the entire solution. A progressive pull broach may generate the spline while the gear is in a machinable condition before heat treatment. If heat treatment then moves a critical profile, a specialized hard-broaching operation may correct a small, controlled allowance. These routes are not interchangeable.<\/p>\n<p>This article covers one exact workpiece: <strong>a transmission gear blank or semi-finished transmission gear with a straight-sided or involute through internal spline<\/strong>. It does not cover a synchronizer hub, differential side gear, CV-joint member, external gear teeth or a helical spline.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Define_the_Exact_Gear_Spline_and_Manufacturing_Stage\"><\/span>Define the Exact Gear, Spline and Manufacturing Stage<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Do not begin with a machine model. Freeze the application:<\/p>\n<figure class=\"wp-block-table\">\n<table>\n<thead>\n<tr>\n<th>Input<\/th>\n<th>Controlled question<\/th>\n<th>Why it matters<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Gear identity<\/td>\n<td>Which transmission gear and variant?<\/td>\n<td>Prevents mixing different hubs, bores and external features<\/td>\n<\/tr>\n<tr>\n<td>Production state<\/td>\n<td>Soft blank, pre-machined part or heat-treated gear?<\/td>\n<td>Separates generation from hard finishing<\/td>\n<\/tr>\n<tr>\n<td>Spline<\/td>\n<td>Straight-sided or involute, through access, drawing\/standard revision<\/td>\n<td>Defines tool form and inspection<\/td>\n<\/tr>\n<tr>\n<td>Bore and faces<\/td>\n<td>Pre-broach dimensions, finish and datums<\/td>\n<td>Control guidance, stock and fixture location<\/td>\n<\/tr>\n<tr>\n<td>Material condition<\/td>\n<td>Alloy, delivery state, hardness and heat-treatment route<\/td>\n<td>Changes force, wear and distortion<\/td>\n<\/tr>\n<tr>\n<td>Adjacent features<\/td>\n<td>External teeth, threads, oil holes, edges and coatings<\/td>\n<td>Establish protected zones<\/td>\n<\/tr>\n<tr>\n<td>Production target<\/td>\n<td>Volume, batch, changeover and capability requirement<\/td>\n<td>Influences tool and machine architecture<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/figure>\n<p>The pre-broach bore must provide positive, controlled stock over the real cutting length. Excessive runout, taper or uneven stock can load one side of the broach and distort the apparent spline result.<\/p>\n<p>For a broad process overview, see the <a href=\"https:\/\/broachingmach.com\/en_ca\/spline-broaching-the-complete-guide\/\">spline broaching guide<\/a>. This Post concentrates on the transmission-gear route, datum, fixture and verification decisions.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Freeze_the_Soft-Broaching_Route\"><\/span>Freeze the Soft-Broaching Route<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Soft broaching generates the spline before final heat treatment, while the gear material remains in a planned machinable condition.<\/p>\n<p>A candidate sequence is:<\/p>\n<ol>\n<li>Prepare the gear blank and controlled pilot bore.<\/li>\n<li>Locate and support the gear on the approved bore\/face datum.<\/li>\n<li>Pull a progressive internal spline broach completely through the workpiece.<\/li>\n<li>Clean and inspect the soft spline, bore and protected surfaces.<\/li>\n<li>Complete heat treatment and remaining finishing operations.<\/li>\n<li>Inspect the final gear in the required condition.<\/li>\n<\/ol>\n<p>The important word is \u201cfinal.\u201d A conforming soft-broached feature can change after heat treatment. Distortion may affect profile, lead, tooth thickness\/space width, runout or fit. Do not release a route only from measurements taken before the remaining thermal and finishing operations.<\/p>\n<p>Soft broaching is often attractive because roughing, semi-finishing and finishing teeth share the profile-generation work in one controlled stroke. It still requires a matched tool design, adequate chip space, stable alignment and a machine that can complete the entire force\/stroke envelope.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Decide_Whether_Hard_Broaching_Is_a_Finishing_Candidate\"><\/span>Decide Whether Hard Broaching Is a Finishing Candidate<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/broachingmach.com\/wp-content\/uploads\/2026\/07\/transmission-gear-soft-hard-route.png\" alt=\"Soft generation and controlled hard-finishing route for a transmission gear spline\"><\/p>\n<p><em>Engineering decision map. Conventional soft broaching generates the spline before heat treatment; hard broaching is considered only for measurable, accessible and controlled post-heat-treatment correction stock.<\/em><\/p>\n<p>Hard broaching should not be described as automatically cutting a complete spline from solid hardened stock. In a controlled transmission-gear route, it is usually a finishing or recalibration candidate after heat treatment.<\/p>\n<p>Before selecting it:<\/p>\n<ul>\n<li>measure representative heat-treated gears;<\/li>\n<li>map the amount and direction of spline distortion;<\/li>\n<li>confirm bulk hardness, case condition and local variation;<\/li>\n<li>verify that a positive, limited finishing allowance exists;<\/li>\n<li>check that the spline remains accessible through the bore;<\/li>\n<li>protect finished external gear teeth and faces;<\/li>\n<li>confirm tool substrate, edge\/coating, machine rigidity and speed control;<\/li>\n<li>define the final inspection and tool-wear signals.<\/li>\n<\/ul>\n<p>If the distortion is excessive, inconsistent or leaves negative stock, one fixed hard broach cannot restore every part. The route may require better soft-process control, a heat-treatment change, another finishing process or a design review.<\/p>\n<p>The <a href=\"https:\/\/broachingmach.com\/en_ca\/hard-broaching-vs-soft-broaching\/\">hard-versus-soft broaching guide<\/a> provides the broader timing comparison.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Define_the_Spline_Datum_and_Protected-Zone_Map\"><\/span>Define the Spline, Datum and Protected-Zone Map<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>\u201cInternal spline accuracy\u201d is not one measurement. The controlled drawing may separate:<\/p>\n<ul>\n<li>major and minor diameters where applicable;<\/li>\n<li>tooth thickness or space width;<\/li>\n<li>profile;<\/li>\n<li>lead;<\/li>\n<li>index;<\/li>\n<li>runout or concentricity to the gear datum;<\/li>\n<li>functional fit;<\/li>\n<li>surface condition and burr;<\/li>\n<li>relation to the approved gear face.<\/li>\n<\/ul>\n<p>The datum strategy must continue through broaching, heat treatment and final inspection. If the gear is located from one face during cutting and another feature during inspection, the measurement plan needs correlation.<\/p>\n<p>Adjacent gear teeth, threads, oil holes, finished faces and coatings are protected zones. They should not be clamped or used as reaction surfaces by default. Loading and unloading must prevent contact damage that a spline measurement would not detect.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Select_the_Internal_Spline_Broach_Conditionally\"><\/span>Select the Internal Spline Broach Conditionally<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>A progressive pull broach is a candidate for the through internal spline. The application determines:<\/p>\n<ul>\n<li>spline standard and form;<\/li>\n<li>number of teeth and profile dimensions;<\/li>\n<li>pre-broach bore and stock distribution;<\/li>\n<li>cutting length;<\/li>\n<li>workpiece material and condition;<\/li>\n<li>roughing, semi-finishing and finishing progression;<\/li>\n<li>rise per tooth and chip space;<\/li>\n<li>guide and pull-end design;<\/li>\n<li>tool material, heat treatment and coating;<\/li>\n<li>regrind and inspection boundary.<\/li>\n<\/ul>\n<p>Do not transfer a tooth load, coating or tool grade from another gear only because both parts are described as alloy steel. The complete material, stock, profile, machine and fluid system controls the result.<\/p>\n<p>BroachingMach\u2019s <a href=\"https:\/\/broachingmach.com\/en_ca\/broach-tools\/spline-broaches\/\">spline broach range<\/a> is a commercial starting point. Final geometry and service expectations require the controlled drawing and representative sample cuts.<\/p>\n<p>The <a href=\"https:\/\/broachingmach.com\/en_ca\/how-to-broaches-design\/\">broach design guide<\/a> explains the broader geometry inputs, but it does not replace the transmission-gear drawing and tool calculation.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Select_the_Machine_From_Force_Stroke_and_Process_Control\"><\/span>Select the Machine From Force, Stroke and Process Control<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>The internal broaching machine must provide:<\/p>\n<ul>\n<li>calculated cutting-force capacity with an approved margin;<\/li>\n<li>usable stroke for the complete broach and workpiece;<\/li>\n<li>sufficient daylight and loading clearance;<\/li>\n<li>compatible pull head and tool connection;<\/li>\n<li>guidance and structural rigidity;<\/li>\n<li>speed range and control for the actual material\/tool route;<\/li>\n<li>reliable fluid delivery, filtration and chip handling;<\/li>\n<li>safe tool retrieval and part handling;<\/li>\n<li>recipe, tool and part-family controls where required.<\/li>\n<\/ul>\n<p>Orientation and drive system answer different questions. Vertical or horizontal describes machine\/workpiece motion and loading. Hydraulic or servo describes the drive. CNC describes control architecture. A hard workpiece does not, by itself, prove that a servo machine is required.<\/p>\n<p>The <a href=\"https:\/\/broachingmach.com\/en_ca\/internal-broaching-machine-guide\/\">internal broaching machine guide<\/a> explains the general architecture. Final selection needs the gear OD, mass, spline length, broach length, force, loading method and production target.<\/p>\n<p>Use the <a href=\"https:\/\/broachingmach.com\/en_ca\/how-to-calculate-broaching-machine-tonnage\/\">broaching-machine tonnage calculation guide<\/a> to structure the force inputs; the approved value must still come from the actual gear, material and broach design.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/broachingmach.com\/wp-content\/uploads\/2024\/05\/40f93c40-820e-49c7-8e65-1f54fb8644df-1024x768.png\" alt=\"BroachingMach servo pull-down internal broaching machine\"><\/p>\n<p><em>BroachingMach product photo of a servo pull-down internal broaching machine. It is a candidate equipment category, not evidence of a transmission-gear project or achieved spline result.<\/em><\/p>\n<p>For a controlled post-heat-treatment application, the <a href=\"https:\/\/broachingmach.com\/en_ca\/servo-broaching-machine\/cnc-high-speed-hard-broaching-machine\/\">CNC high-speed hard broaching machine<\/a> is another candidate category. Suitability still depends on the drawing, hardness\/allowance distribution, force, stroke, tooling and sample evidence.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Build_the_Gear_Fixture_and_Pull-Broach_Alignment\"><\/span>Build the Gear Fixture and Pull-Broach Alignment<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/broachingmach.com\/wp-content\/uploads\/2026\/07\/transmission-gear-fixture-alignment.png\" alt=\"Transmission gear spline broaching datum, support and alignment concept\"><\/p>\n<p><em>Non-dimensional engineering diagram of a candidate face\/bore datum, pull-broach alignment, support, protected external teeth and chip exit. Final contacts require the controlled gear drawing.<\/em><\/p>\n<p>The cutting-force path should close through the tool, spline stock, supported gear zone, fixture and machine structure. The fixture must not simply hold the part; it must prevent tilt and movement without damaging external teeth or finished faces.<\/p>\n<p>Review:<\/p>\n<ul>\n<li>primary face and bore datum;<\/li>\n<li>seating cleanliness and burr control;<\/li>\n<li>support beneath a rigid approved zone;<\/li>\n<li>anti-rotation only where needed and permitted;<\/li>\n<li>no-clamp zones around external teeth, threads, thin edges and oil features;<\/li>\n<li>full broach and chip exit below or beyond the workpiece;<\/li>\n<li>loading access without striking the tool;<\/li>\n<li>free-state inspection after unloading.<\/li>\n<\/ul>\n<p>The broach, pilot bore and pull path must share the intended axis. Increasing machine force cannot compensate for a tilted gear, worn pull head or misaligned guide.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Control_Chips_Fluid_and_Tool_Condition\"><\/span>Control Chips, Fluid and Tool Condition<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Successive teeth create and carry a significant chip volume. The gullet design, cutting length and fluid\/chip route must prevent packing and recutting.<\/p>\n<p>Monitor:<\/p>\n<ul>\n<li>load\/force trend for the matched gear and material lot;<\/li>\n<li>chip shape and evacuation;<\/li>\n<li>pickup, smearing or scoring;<\/li>\n<li>surface and burr changes;<\/li>\n<li>dimensional\/profile drift;<\/li>\n<li>abnormal noise, vibration or part movement;<\/li>\n<li>broach wear, chipping and guide damage;<\/li>\n<li>fluid delivery, cleanliness, condition and temperature.<\/li>\n<\/ul>\n<p>A single force increase or surface mark does not prove one cause. Compare part, process and tool evidence before changing speed, fluid, alignment or tooling.<\/p>\n<p>Do not set a universal number of gears between inspections or resharpening. Establish tool-history and removal criteria from the controlled application.<\/p>\n<p>The <a href=\"https:\/\/broachingmach.com\/en_ca\/how-to-choose-the-right-cutting-fluid-for-broaching-machines\/\">broaching cutting-fluid guide<\/a> provides a selection framework for lubricity, cooling, filtration and chip transport.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Inspect_the_Finished_Internal_Spline\"><\/span>Inspect the Finished Internal Spline<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Inspection must follow the drawing and spline standard. Candidate methods include:<\/p>\n<ul>\n<li>composite or sector gauges for functional fit;<\/li>\n<li>measurement over pins\/balls or span where applicable;<\/li>\n<li>analytical profile, lead and index measurement;<\/li>\n<li>major\/minor diameter checks;<\/li>\n<li>CMM or gear-metrology inspection;<\/li>\n<li>runout\/concentricity to the approved datum;<\/li>\n<li>surface, burr and protected-zone inspection.<\/li>\n<\/ul>\n<p>The reference method, gauge calibration and supplier\/customer correlation should be agreed before sample release. A machine screen, pull-force trace or in-clamp measurement is process evidence, not a substitute for final free-state gear inspection.<\/p>\n<p>For hard broaching, compare measurements before and after heat treatment and after the correction operation. That evidence shows whether stock is present where the tool can remove it and whether the final route is repeatable.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Sample-Test_and_Release_Plan\"><\/span>Sample-Test and Release Plan<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Use representative normal and worst-case parts:<\/p>\n<ol>\n<li>Freeze the gear drawing, material and heat-treatment records.<\/li>\n<li>Map the pre-broach bore and stock.<\/li>\n<li>Qualify the broach, pull end, guide, fixture and machine.<\/li>\n<li>Verify force, stroke, daylight, speed and chip\/fluid route.<\/li>\n<li>Cut and inspect soft gears.<\/li>\n<li>Complete heat treatment and map distortion.<\/li>\n<li>Apply hard finishing only to the approved allowance, if required.<\/li>\n<li>Inspect profile, lead, index, fit, datum relationship and surface.<\/li>\n<li>Check external teeth, faces and other protected zones.<\/li>\n<li>Record tool condition and load\/chip behavior.<\/li>\n<li>Repeat setups over an agreed sample.<\/li>\n<li>Separate sample approval, machine FAT\/SAT and stable production evidence.<\/li>\n<\/ol>\n<p>One completed stroke proves access, not production capability. Release requires repeatable part, process and tool evidence.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Information_Needed_for_a_Transmission_Gear_Spline_Proposal\"><\/span>Information Needed for a Transmission Gear Spline Proposal<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Provide:<\/p>\n<ul>\n<li>controlled gear drawing, spline standard and CAD model;<\/li>\n<li>exact gear identity and variants;<\/li>\n<li>material, delivery condition and heat-treatment sequence;<\/li>\n<li>hardness\/case data and measured heat-treatment distortion;<\/li>\n<li>pre-broach bore, cutting length and stock map;<\/li>\n<li>required profile, lead, index, fit and datum relationship;<\/li>\n<li>external teeth, faces, threads, holes and protected surfaces;<\/li>\n<li>annual volume, batch size, loading and takt target;<\/li>\n<li>existing broach\/machine\/fixture\/fluid information;<\/li>\n<li>reference gauges and inspection method;<\/li>\n<li>representative normal and worst-case gears.<\/li>\n<\/ul>\n<p>These inputs allow BroachingMach to evaluate the candidate broach, machine architecture, fixture, chip-control and inspection plan. Final force, stroke, tool geometry, cycle time, capability and tool-life expectations follow drawing review, calculation and sample broaching.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Frequently_Asked_Questions\"><\/span>Frequently Asked Questions<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<h3><span class=\"ez-toc-section\" id=\"Should_a_transmission_gear_spline_be_broached_before_heat_treatment\"><\/span>Should a transmission gear spline be broached before heat treatment?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Often the spline is generated in a machinable condition before heat treatment, but final capability depends on the later distortion and inspection result. The complete route must be validated.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Can_hard_broaching_generate_the_full_spline\"><\/span>Can hard broaching generate the full spline?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Do not assume so. Hard broaching is generally considered for a small, controlled and accessible finishing allowance after heat treatment. Excessive, uneven or negative stock may require another route.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Does_a_hard_gear_automatically_require_a_servo_broaching_machine\"><\/span>Does a hard gear automatically require a servo broaching machine?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>No. Material condition is one input. Force, stroke, speed control, rigidity, tool design, allowance and production requirements decide the machine architecture.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Can_the_same_broach_run_every_gear_variant\"><\/span>Can the same broach run every gear variant?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Only if the profile, bore, material\/condition, cutting length, stock, interface and inspection requirements remain inside the validated tool envelope. Similar product names are not enough.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"How_is_an_internal_spline_inspected\"><\/span>How is an internal spline inspected?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>The drawing and spline standard determine the method. Functional gauges, analytical gear measurement, pins\/span and CMM may serve different controls; they should be correlated to the customer reference.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Final_Recommendation\"><\/span>Final Recommendation<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Choose the transmission-gear spline route from the final inspected workpiece backward. Freeze the gear, through spline, material, heat-treatment stage, stock, datum and protected zones; then select the broach, machine, fixture and inspection plan.<\/p>\n<p>Send BroachingMach the controlled drawing, material\/heat-treatment data, distortion map, volume, reference gauge and representative samples through the <a href=\"https:\/\/broachingmach.com\/en_ca\/contact\/\">contact page<\/a>. The proposal should define a testable soft, hard-finish or alternative route\u2014not promise one universal tool or machine for every transmission gear.<\/p>","protected":false},"excerpt":{"rendered":"<p>Plan a transmission gear through internal spline from the soft and hard process route to the broach, machine, fixture, inspection and sample evidence.<\/p>","protected":false},"author":1,"featured_media":6546,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[23],"tags":[],"class_list":["post-6549","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-broaching"],"_links":{"self":[{"href":"https:\/\/broachingmach.com\/en_ca\/wp-json\/wp\/v2\/posts\/6549","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/broachingmach.com\/en_ca\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/broachingmach.com\/en_ca\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/broachingmach.com\/en_ca\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/broachingmach.com\/en_ca\/wp-json\/wp\/v2\/comments?post=6549"}],"version-history":[{"count":1,"href":"https:\/\/broachingmach.com\/en_ca\/wp-json\/wp\/v2\/posts\/6549\/revisions"}],"predecessor-version":[{"id":6563,"href":"https:\/\/broachingmach.com\/en_ca\/wp-json\/wp\/v2\/posts\/6549\/revisions\/6563"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/broachingmach.com\/en_ca\/wp-json\/wp\/v2\/media\/6546"}],"wp:attachment":[{"href":"https:\/\/broachingmach.com\/en_ca\/wp-json\/wp\/v2\/media?parent=6549"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/broachingmach.com\/en_ca\/wp-json\/wp\/v2\/categories?post=6549"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/broachingmach.com\/en_ca\/wp-json\/wp\/v2\/tags?post=6549"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}