{"id":13868,"date":"2026-07-30T06:48:43","date_gmt":"2026-07-30T06:48:43","guid":{"rendered":"https:\/\/hlh-js.com\/?p=13868"},"modified":"2026-07-30T06:48:43","modified_gmt":"2026-07-30T06:48:43","slug":"dimensional-accuracy-and-tolerances-after-ceramic-bead-blasting-sls-nylon-parts","status":"publish","type":"post","link":"https:\/\/hlh-js.com\/zh\/resource\/blog\/dimensional-accuracy-and-tolerances-after-ceramic-bead-blasting-sls-nylon-parts\/","title":{"rendered":"Dimensional Accuracy and Tolerances After Ceramic Bead Blasting SLS Nylon Parts"},"content":{"rendered":"<script type=\"application\/ld+json\">{\n    \"@context\": \"https:\\\/\\\/schema.org\",\n    \"@graph\": [\n        {\n            \"@type\": \"Article\",\n            \"headline\": \"Dimensional Accuracy and Tolerances After Ceramic Bead Blasting SLS Nylon Parts\",\n            \"description\": \"Quantitative guide to dimensional accuracy after ceramic bead blasting SLS nylon parts \\u2014 covering what is removed and why, material removal data by bead grade and pressure, OD vs ID behaviour, tolerance implications by class, design compensation rules, and first-article measurement protocol.\",\n            \"datePublished\": \"2026-07-27\",\n            \"dateModified\": \"2026-07-27\",\n            \"author\": {\n                \"@type\": \"Organization\",\n                \"name\": \"Jiangsu Henglihong Technology Co., Ltd.\",\n                \"url\": \"https:\\\/\\\/hlh-js.com\"\n            },\n            \"publisher\": {\n                \"@type\": \"Organization\",\n                \"name\": \"Jiangsu Henglihong Technology Co., Ltd.\",\n                \"url\": \"https:\\\/\\\/hlh-js.com\"\n            },\n            \"mainEntityOfPage\": {\n                \"@type\": \"WebPage\",\n                \"@id\": \"https:\\\/\\\/hlh-js.com\\\/resource\\\/blog\\\/dimensional-accuracy-and-tolerances-after-ceramic-bead-blasting-sls-nylon-parts\\\/\"\n            }\n        },\n        {\n            \"@type\": \"FAQPage\",\n            \"mainEntity\": [\n                {\n                    \"@type\": \"Question\",\n                    \"name\": \"How much material does ceramic bead blasting remove from PA12 SLS parts?\",\n                    \"acceptedAnswer\": {\n                        \"@type\": \"Answer\",\n                        \"text\": \"A standard ceramic bead blast cycle using ZS beads at 0.15\\u20130.25 mm and 60\\u201365 PSI for 7 minutes removes approximately 20\\u201355 \\u00b5m from external OD surfaces of PA12 SLS parts per cycle. This material is primarily the semi-sintered surface skin, not the bulk sintered nylon substrate. Internal ID dimensions are affected less \\u2014 typically 7\\u201318 \\u00b5m per cycle \\u2014 because internal features receive less direct and less uniform blast coverage than external surfaces. For most SLS applications with tolerances of \\u00b10.2 mm or wider, this removal is negligible relative to the tolerance band.\"\n                    }\n                },\n                {\n                    \"@type\": \"Question\",\n                    \"name\": \"Does ceramic bead blasting affect internal hole dimensions differently than external dimensions?\",\n                    \"acceptedAnswer\": {\n                        \"@type\": \"Answer\",\n                        \"text\": \"Yes \\u2014 internal ID dimensions experience approximately 2\\u20134\\u00d7 less material removal than external OD dimensions under equivalent blast conditions, because blast coverage inside holes and channels is indirect and partial rather than direct and uniform. Beads enter channels, impact the internal wall, and exit, but with less perpendicular impact energy than on an external face exposed to direct nozzle impingement. For most SLS part designs, this means internal holes and channels require no dimensional compensation, while external OD features with tight tolerances (\\u00b10.1 mm or less) may benefit from a small compensation of 15\\u201340 \\u00b5m applied in the CAD model.\"\n                    }\n                },\n                {\n                    \"@type\": \"Question\",\n                    \"name\": \"Can ceramic bead blasting be used on SLS parts with \\u00b10.1 mm tolerances?\",\n                    \"acceptedAnswer\": {\n                        \"@type\": \"Answer\",\n                        \"text\": \"Yes, with appropriate protocol selection. For \\u00b10.1 mm tolerances, use fine ZS beads at 0.10\\u20130.15 mm, reduced pressure (45\\u201355 PSI), and a single cycle of 8\\u201314 minutes. At these parameters, material removal is typically 8\\u201322 \\u00b5m per external surface \\u2014 well within a \\u00b10.1 mm tolerance band (which has 100 \\u00b5m on each side). Always verify by first-article dimensional measurement before production commitment. For tolerances tighter than \\u00b10.05 mm, ceramic bead blasting is not recommended; consider alternative post-processing methods or selective masking of tight-tolerance features during blasting.\"\n                    }\n                },\n                {\n                    \"@type\": \"Question\",\n                    \"name\": \"Should I design dimensional compensation into SLS parts that will be ceramic bead blasted?\",\n                    \"acceptedAnswer\": {\n                        \"@type\": \"Answer\",\n                        \"text\": \"For most SLS applications with tolerances of \\u00b10.2 mm or wider, dimensional compensation is not needed \\u2014 the material removal from a standard blast cycle is well within the tolerance budget. For external OD features with tolerances of \\u00b10.1 to \\u00b10.15 mm, adding 20\\u201340 \\u00b5m to the intended dimension in the CAD file is a reasonable precaution. Do not compensate internal ID dimensions unless first-article measurement shows significant removal \\u2014 which is uncommon for standard channel geometries. When in doubt, blast a first-article sample without compensation, measure, and apply compensation only where measurement shows it is needed.\"\n                    }\n                }\n            ]\n        }\n    ]\n}<\/script>\n<style>\n.hlh-sls-c08{font-family:'Segoe UI',Arial,sans-serif;color:#2c3e50;line-height:1.82;max-width:860px;margin:0 auto;font-size:16px}\n.hlh-sls-c08 h1{font-size:2rem;color:#1a3456;font-weight:700;line-height:1.28;margin:0 0 .5rem}\n.hlh-sls-c08 h2{font-size:1.46rem;color:#1a3456;font-weight:700;margin:2.5rem 0 .72rem;padding-bottom:.4rem;border-bottom:3px solid #d86e18}\n.hlh-sls-c08 h3{font-size:1.14rem;color:#1a3456;font-weight:700;margin:1.75rem 0 .5rem}\n.hlh-sls-c08 h4{font-size:1rem;color:#d86e18;font-weight:700;margin:1.2rem 0 .35rem}\n.hlh-sls-c08 p{margin:0 0 1rem}.hlh-sls-c08 ul,.hlh-sls-c08 ol{margin:0 0 1rem 1.5rem;padding:0}.hlh-sls-c08 li{margin-bottom:.38rem}\n.hlh-sls-c08 a{color:#d86e18;text-decoration:none;border-bottom:1px solid 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a{display:block;font-weight:600;font-size:.9rem;color:#1a3456;border:none;margin-bottom:.22rem;line-height:1.4}.hlh-sls-c08 .rel-c a:hover{color:#d86e18}\n.hlh-sls-c08 .rel-c p{font-size:.81rem;color:#4a6278;margin:0;line-height:1.43}\n.hlh-sls-c08 .fi{border:1px solid #c9d8e8;border-radius:6px;margin-bottom:.52rem;overflow:hidden}\n.hlh-sls-c08 .fq{background:#f0f4f8;padding:.9rem 1.2rem;font-weight:600;font-size:.94rem;color:#1a3456;cursor:pointer;display:flex;justify-content:space-between;align-items:center;border:none;width:100%;text-align:left;transition:background .18s}.hlh-sls-c08 .fq:hover{background:#e4edf6}\n.hlh-sls-c08 .fi-icon{font-size:1.2rem;color:#d86e18;flex-shrink:0;margin-left:.9rem;transition:transform .22s;font-weight:400}.hlh-sls-c08 .fq.open .fi-icon{transform:rotate(45deg)}\n.hlh-sls-c08 .fa{display:none;padding:.88rem 1.2rem 1rem;font-size:.92rem;background:#fff;color:#2c3e50;line-height:1.78;border-top:1px solid #e2eaf2}.hlh-sls-c08 .fa.open{display:block}.hlh-sls-c08 .fa p:last-child{margin-bottom:0}\n.hlh-sls-c08 .cta{background:linear-gradient(135deg,#1a3456 0%,#24466e 100%);border-radius:10px;padding:2rem 2.3rem;margin:2.8rem 0 1rem;text-align:center}\n.hlh-sls-c08 .cta h3{color:#fff;font-size:1.28rem;margin:0 0 .6rem}.hlh-sls-c08 .cta p{color:rgba(255,255,255,.84);font-size:.94rem;margin-bottom:1.3rem}\n.hlh-sls-c08 .btn{display:inline-block;background:#d86e18;color:#fff!important;font-weight:700;font-size:1rem;padding:.73rem 2.1rem;border-radius:4px;text-decoration:none!important;border:none!important;transition:background .2s}.hlh-sls-c08 .btn:hover{background:#b85a10}\n@media(max-width:640px){.hlh-sls-c08 h1{font-size:1.5rem}.hlh-sls-c08 h2{font-size:1.2rem}.hlh-sls-c08 .cta{padding:1.5rem 1.2rem}}\n<\/style>\n<article class=\"hlh-sls-c08\">\n<div class=\"back\">&#8592; Part of: <a href=\"https:\/\/hlh-js.com\/resource\/blog\/ceramic-beads-sls-powder-removal-complete-guide\/\" target=\"_blank\" rel=\"noopener noreferrer\">Ceramic Beads for SLS Powder Removal \u2014 Complete Guide<\/a><\/div>\n<h1>Dimensional Accuracy and Tolerances After Ceramic Bead Blasting SLS Nylon Parts<\/h1>\n<p class=\"meta\">By Jiangsu Henglihong Technology Co., Ltd. &nbsp;|&nbsp; Last updated: July 2026<\/p>\n<p class=\"lead\">Ceramic bead blasting removes material from SLS nylon parts \u2014 but in small, controlled, and well-characterised quantities. For the majority of SLS applications, the dimensional change is negligible relative to standard SLS tolerances. For tighter-tolerance parts, the same data that shows the change also shows the path to staying within specification. This article provides the material removal data, OD vs. ID comparison, tolerance implications by class, design compensation rules, and the first-article measurement protocol that should underpin any precision SLS depowdering operation.<\/p>\n<div class=\"stats\">\n  <div class=\"stat\"><span class=\"stat-n\">20\u201355 \u00b5m<\/span><span class=\"stat-l\">External OD removal per standard blast cycle (ZS, 0.15\u20130.25 mm, 62 PSI)<\/span><\/div>\n  <div class=\"stat\"><span class=\"stat-n\">7\u201318 \u00b5m<\/span><span class=\"stat-l\">Internal ID removal per standard blast cycle (same conditions)<\/span><\/div>\n  <div class=\"stat\"><span class=\"stat-n\">\u00b10.2 mm<\/span><span class=\"stat-l\">Tolerance class at which no compensation is typically needed<\/span><\/div>\n  <div class=\"stat\"><span class=\"stat-n\">2\u20134\u00d7<\/span><span class=\"stat-l\">Ratio of OD to ID material removal at equivalent blast conditions<\/span><\/div>\n<\/div>\n<nav class=\"toc\"><p class=\"toc-h\">Table of Contents<\/p>\n<ol>\n<li><a href=\"#c08-what\">What Ceramic Bead Blasting Actually Removes from SLS Parts<\/a><\/li>\n<li><a href=\"#c08-data\">Material Removal Data by Bead Grade, Size, and Pressure<\/a><\/li>\n<li><a href=\"#c08-odid\">OD vs. ID: Why External and Internal Dimensions Behave Differently<\/a><\/li>\n<li><a href=\"#c08-tol\">Tolerance Implications by SLS Tolerance Class<\/a><\/li>\n<li><a href=\"#c08-comp\">Design Compensation: When and How to Apply<\/a><\/li>\n<li><a href=\"#c08-fa\">First-Article Dimensional Qualification Protocol<\/a><\/li>\n<li><a href=\"#c08-reg\">Documentation for Regulated Applications<\/a><\/li>\n<li><a href=\"#c08-faq\">Frequently Asked Questions<\/a><\/li>\n<\/ol><\/nav>\n\n<h2 id=\"c08-what\">1. What Ceramic Bead Blasting Actually Removes from SLS Parts<\/h2>\n<p>A common concern about introducing ceramic bead blasting into SLS post-processing is that it erodes the part and compromises dimensional accuracy. Understanding <em>what<\/em> is removed \u2014 and the mechanism by which it is removed \u2014 puts this concern in the correct proportions.<\/p>\n<p>SLS nylon parts have a layered surface structure immediately after build. The outermost zone is the <strong>semi-sintered skin<\/strong>: a layer of partially fused nylon particles, typically 80\u2013250 \u00b5m thick, that is bonded to the part surface but has lower density (approximately 70\u201385% of bulk nylon density) and lower cohesive strength than the fully sintered interior. This skin is what compressed-air blow-off fails to remove, and what ceramic bead blasting targets.<\/p>\n<p>When a ceramic bead impacts the part surface, it delivers a compressive impulse that breaks the inter-particle bonds within the semi-sintered skin, dislodging the skin material from the surface of the bulk sintered part beneath. The material &#8220;removed&#8221; is therefore primarily the skin \u2014 lower-density, partially-sintered nylon that is not part of the functional part geometry \u2014 rather than the bulk sintered substrate. The bulk substrate material that <em>is<\/em> removed is a surface layer typically 10\u201340 \u00b5m deep, not the full skin thickness.<\/p>\n<p>This distinction matters because the semi-sintered skin itself contributes to the as-built dimension of the part. Removing it produces a slight dimensional reduction \u2014 the part is slightly smaller post-blast than as-built \u2014 but this reduction is the removal of non-functional material that was always intended to be depowdered.<\/p>\n\n<h2 id=\"c08-data\">2. Material Removal Data by Bead Grade, Size, and Pressure<\/h2>\n<div class=\"tw\"><table><thead><tr><th>Bead Grade \/ Size<\/th><th>Pressure<\/th><th>Cycle<\/th><th>External OD Removal<\/th><th>Internal ID Removal<\/th><th>Edge \/ Corner Removal<\/th><\/tr><\/thead>\n<tbody>\n<tr><td><strong>ZrO\u2082 0.15\u20130.25 mm<\/strong><\/td><td>65 PSI<\/td><td>7 min<\/td><td>25\u201360 \u00b5m<\/td><td>8\u201320 \u00b5m<\/td><td>40\u2013100 \u00b5m<\/td><\/tr>\n<tr><td><strong>ZS 0.15\u20130.25 mm<\/strong><\/td><td>62 PSI<\/td><td>7 min<\/td><td>20\u201355 \u00b5m<\/td><td>7\u201318 \u00b5m<\/td><td>35\u201385 \u00b5m<\/td><\/tr>\n<tr><td><strong>ZS 0.10\u20130.15 mm<\/strong><\/td><td>52 PSI<\/td><td>10 min<\/td><td>10\u201332 \u00b5m<\/td><td>4\u201312 \u00b5m<\/td><td>18\u201350 \u00b5m<\/td><\/tr>\n<tr><td><strong>ZS 0.10\u20130.15 mm<\/strong><\/td><td>45 PSI<\/td><td>12 min<\/td><td>8\u201322 \u00b5m<\/td><td>3\u20139 \u00b5m<\/td><td>14\u201338 \u00b5m<\/td><\/tr>\n<tr><td><strong>ZS 0.05\u20130.10 mm<\/strong><\/td><td>46 PSI<\/td><td>16 min<\/td><td>5\u201315 \u00b5m<\/td><td>2\u20137 \u00b5m<\/td><td>10\u201325 \u00b5m<\/td><\/tr>\n<\/tbody><\/table><\/div>\n<p>Edge and corner removal is higher than flat-face OD removal because edges receive concentrated blast impact from multiple angles simultaneously during the blast cycle. For parts where sharp external edges are a functional requirement, this higher edge removal must be accounted for in both the design compensation and the first-article measurement plan.<\/p>\n\n<h2 id=\"c08-odid\">3. OD vs. ID: Why External and Internal Dimensions Behave Differently<\/h2>\n<p>External OD dimensions experience greater material removal than internal ID dimensions because the physics of blast coverage differs fundamentally between external and internal surfaces.<\/p>\n<p>On external surfaces, the blast nozzle can be positioned to deliver direct, near-perpendicular impact to the surface. The bead arrives with full kinetic energy at near-optimal impact angle, maximising material removal per impact. External surfaces receive hundreds of impacts per unit area throughout the blast cycle.<\/p>\n<p>Inside a bore, channel, or recessed feature, the geometry limits how the bead can arrive. Beads enter the feature, scatter off the internal walls, and exit \u2014 but the indirect, lower-angle impacts carry less effective material removal per impact. Blind features receive even less coverage than through-channels because beads cannot exit and must rely on ricochet impacts alone.<\/p>\n<p>The practical result: OD removal is approximately 2\u20134\u00d7 greater than ID removal for the same blast cycle. This means:<\/p>\n<ul>\n<li><strong>External OD features shrink more per cycle<\/strong> than internal ID features grow per cycle<\/li>\n<li>Design compensation (if needed) targets external OD dimensions, not internal holes or channels<\/li>\n<li>Internal channel diameters are rarely affected significantly enough to require compensation at tolerances of \u00b10.2 mm or wider<\/li>\n<\/ul>\n\n<h2 id=\"c08-tol\">4. Tolerance Implications by SLS Tolerance Class<\/h2>\n<div class=\"tw\"><table><thead><tr><th>Tolerance Class<\/th><th>Typical SLS Application<\/th><th>Impact of Standard Blast<\/th><th>Action Required<\/th><\/tr><\/thead>\n<tbody>\n<tr><td><strong>\u00b10.3 mm and wider<\/strong><\/td><td>Non-critical functional parts, visual models<\/td><td>Negligible (removal &lt;20% of tolerance band)<\/td><td>No action; blast with standard protocol<\/td><\/tr>\n<tr><td><strong>\u00b10.2 mm<\/strong><\/td><td>General functional SLS parts<\/td><td>Small (removal &lt;30% of tolerance band)<\/td><td>No compensation; verify with first article<\/td><\/tr>\n<tr><td><strong>\u00b10.1 mm<\/strong><\/td><td>Mating features, precision assemblies<\/td><td>Moderate (removal 10\u201360% of tolerance band for OD)<\/td><td>Use fine-bead low-pressure protocol; first-article measurement mandatory<\/td><\/tr>\n<tr><td><strong>\u00b10.05 mm<\/strong><\/td><td>High-precision interfaces<\/td><td>Significant; removal approaches or exceeds tolerance band for OD<\/td><td>Ceramic bead blasting not recommended; mask tight features or use alternative finishing<\/td><\/tr>\n<\/tbody><\/table><\/div>\n<p>SLS nylon parts inherently carry build-to-build dimensional variation of approximately \u00b10.1 to \u00b10.2 mm from the sintering process itself. Specifying \u00b10.05 mm tolerances on as-built SLS parts \u2014 before any post-processing \u2014 is generally inappropriate for the process. Ceramic bead blasting adds a small, predictable, controllable dimensional change on top of this inherent SLS variation.<\/p>\n\n<h2 id=\"c08-comp\">5. Design Compensation: When and How to Apply<\/h2>\n<p>Design compensation means adjusting the intended dimension in the CAD model upward (for OD features that will be blasted) so that the post-blast final dimension lands on the target. It is not always necessary \u2014 for most SLS tolerances of \u00b10.2 mm or wider, the blast-induced change is small enough that no compensation is needed.<\/p>\n<div class=\"box box-a\">\n<h4>Design compensation rules for ceramic bead blasted SLS parts<\/h4>\n<ul>\n<li><strong>External OD, \u00b10.2 mm tolerance or wider:<\/strong> no compensation needed<\/li>\n<li><strong>External OD, \u00b10.1\u20130.15 mm tolerance, standard blast:<\/strong> add 20\u201340 \u00b5m to the intended dimension in the CAD model<\/li>\n<li><strong>External OD, \u00b10.1\u20130.15 mm tolerance, fine-bead low-pressure blast:<\/strong> add 10\u201325 \u00b5m<\/li>\n<li><strong>External sharp edges (acute angle features):<\/strong> consider adding 30\u201360 \u00b5m or applying a small design radius to prevent disproportionate blast removal<\/li>\n<li><strong>Internal ID (holes, bores, channels), \u00b10.2 mm or wider:<\/strong> no compensation needed<\/li>\n<li><strong>Internal ID, \u00b10.1 mm:<\/strong> measure first article without compensation; apply only if first-article data shows removal exceeding 50% of tolerance budget<\/li>\n<\/ul>\n<\/div>\n<p><strong>Always verify compensation by first-article measurement<\/strong> before applying it to production. Compensation values are calculated from the data ranges in Section 2; actual removal on a specific part geometry may be at the low or high end of these ranges depending on feature size, blast angle, and coverage uniformity. Applying a compensation value from a reference table without verification can create a new dimensional non-conformance if the actual removal is lower than the range maximum used to derive the compensation.<\/p>\n\n<h2 id=\"c08-fa\">6. First-Article Dimensional Qualification Protocol<\/h2>\n<p>The first-article dimensional qualification establishes whether the ceramic bead blast protocol produces acceptable dimensional outcomes for a specific part design. It must be performed for every new part design and whenever the blast protocol changes materially (bead grade, size, pressure, or cycle time).<\/p>\n<ol>\n<li><strong>Baseline measurement (pre-blast):<\/strong> measure all reference dimensions on the first-article part before blasting, using calibrated calipers or CMM. Include at minimum: one external OD (longest or tightest-tolerance external dimension), one external edge dimension, one internal bore or channel diameter (if present)<\/li>\n<li><strong>Blast at specified protocol:<\/strong> bead grade, size, pressure, nozzle, cycle time as documented<\/li>\n<li><strong>Post-blast measurement:<\/strong> measure the same reference dimensions on the same part using the same instrument and technique as the baseline measurement<\/li>\n<li><strong>Calculate removal:<\/strong> baseline \u2212 post-blast = material removal per surface per cycle. Record for each reference dimension separately<\/li>\n<li><strong>Compare against tolerance budget:<\/strong> confirm that post-blast dimensions fall within the tolerance specification. If OD dimensions show removal exceeding 50% of the tolerance budget, consider fine-bead protocol or design compensation<\/li>\n<li><strong>Approve and document:<\/strong> the qualified protocol, measurement data, and pass\/fail criteria become the production process specification for this part<\/li>\n<\/ol>\n\n<h2 id=\"c08-reg\">7. Documentation for Regulated Applications<\/h2>\n<p>SLS parts for medical devices (ISO 13485 \/ FDA 21 CFR Part 820), aerospace (AS9100 \/ NADCAP), and automotive safety applications (IATF 16949) require the blast process to be validated as a special process and documented in the manufacturing record.<\/p>\n<p>The minimum documentation requirement for each production batch includes: part number and revision; ceramic bead grade, composition, and size range; blast cabinet type and qualification status; inlet pressure (PSI) measured at nozzle; cycle time; media charge age (cycles since last replacement or top-up); operator identification; and the dimensional measurement result on the qualification coupon for that batch.<\/p>\n<p>Jiangsu Henglihong Technology Co., Ltd. provides Certificate of Conformance (CoC) documents, material data sheets (composition, density, hardness), and lot-specific PSD data for all ceramic bead grades. These documents support customer process validation dossiers under ISO 13485, AS9100, and equivalent quality management standards.<\/p>\n\n<h2 id=\"c08-faq\">Frequently Asked Questions<\/h2>\n<div>\n<div class=\"fi\"><button class=\"fq\" aria-expanded=\"false\">How much material does ceramic bead blasting remove from PA12 SLS parts? <span class=\"fi-icon\">+<\/span><\/button>\n<div class=\"fa\"><p>A standard blast cycle using ZS beads at 0.15\u20130.25 mm and 60\u201365 PSI for 7 minutes removes approximately 20\u201355 \u00b5m from external OD surfaces of PA12 SLS parts. This material is primarily the semi-sintered surface skin \u2014 not the bulk sintered nylon substrate. Internal ID dimensions are affected less: typically 7\u201318 \u00b5m per cycle. For tighter-tolerance applications, the fine-bead protocol (0.10\u20130.15 mm at 45\u201352 PSI) reduces OD removal to 8\u201322 \u00b5m, staying well within a \u00b10.1 mm tolerance budget.<\/p><\/div><\/div>\n<div class=\"fi\"><button class=\"fq\" aria-expanded=\"false\">Does ceramic bead blasting affect internal holes differently than external dimensions? <span class=\"fi-icon\">+<\/span><\/button>\n<div class=\"fa\"><p>Yes \u2014 internal ID dimensions experience approximately 2\u20134\u00d7 less material removal than external OD dimensions under equivalent blast conditions. This is because blast coverage inside holes and channels is indirect and partial: beads enter, scatter off internal walls, and exit without the near-perpendicular direct impact that external surfaces receive. For most SLS part designs at tolerances of \u00b10.2 mm or wider, internal dimensions require no compensation. External OD features with \u00b10.1\u20130.15 mm tolerances may benefit from 10\u201340 \u00b5m of design compensation, verified by first-article measurement.<\/p><\/div><\/div>\n<div class=\"fi\"><button class=\"fq\" aria-expanded=\"false\">Can ceramic bead blasting be used on SLS parts with \u00b10.1 mm tolerances? <span class=\"fi-icon\">+<\/span><\/button>\n<div class=\"fa\"><p>Yes, with appropriate protocol selection. For \u00b10.1 mm tolerances, use fine ZS beads at 0.10\u20130.15 mm, reduced pressure (45\u201352 PSI), and a single cycle. At these parameters, OD material removal is typically 8\u201322 \u00b5m \u2014 well within a \u00b10.1 mm tolerance band of 100 \u00b5m total. Verify by first-article dimensional measurement before production commitment, and document the protocol as a controlled special process. For tolerances tighter than \u00b10.05 mm, ceramic bead blasting is not recommended; consider masking tight-tolerance features during blasting.<\/p><\/div><\/div>\n<div class=\"fi\"><button class=\"fq\" aria-expanded=\"false\">Should I apply dimensional compensation to SLS parts that will be ceramic bead blasted? <span class=\"fi-icon\">+<\/span><\/button>\n<div class=\"fa\"><p>For most SLS applications with tolerances of \u00b10.2 mm or wider, no compensation is needed \u2014 the blast-induced removal is small relative to the tolerance band. For external OD features with \u00b10.1\u20130.15 mm tolerances, adding 20\u201340 \u00b5m to the intended CAD dimension is a reasonable precaution with a standard blast protocol, reduced to 10\u201325 \u00b5m with a fine-bead low-pressure protocol. Internal ID features generally require no compensation unless first-article measurement shows otherwise. Always verify compensation values by first-article measurement \u2014 do not rely on tabulated values alone without confirming they apply to your specific geometry.<\/p><\/div><\/div>\n<\/div>\n\n<h2>Related Articles in This Series<\/h2>\n<p>Return to the <a href=\"https:\/\/hlh-js.com\/resource\/blog\/ceramic-beads-sls-powder-removal-complete-guide\/\" target=\"_blank\" rel=\"noopener noreferrer\">Ceramic Beads for SLS Powder Removal \u2014 Complete Guide<\/a> for the full overview.<\/p>\n<div class=\"rel-g\">\n<div class=\"rel-c\"><a href=\"https:\/\/hlh-js.com\/resource\/blog\/surface-finish-and-ra-values-after-ceramic-bead-blasting-sls-3d-printed-parts\/\" target=\"_blank\" rel=\"noopener noreferrer\">Surface Finish Ra Values After Ceramic Bead Blasting<\/a><p>The companion quality metric \u2014 Ra data and measurement protocol for SLS depowdering QC.<\/p><\/div>\n<div class=\"rel-c\"><a href=\"https:\/\/hlh-js.com\/resource\/blog\/blast-pressure-and-cycle-time-for-ceramic-bead-sls-depowdering-optimization-guide\/\" target=\"_blank\" rel=\"noopener noreferrer\">Blast Pressure and Cycle Time Optimization<\/a><p>How pressure and cycle time control the material removal rate from SLS parts.<\/p><\/div>\n<div class=\"rel-c\"><a href=\"https:\/\/hlh-js.com\/resource\/blog\/ceramic-bead-size-selection-for-sls-powder-removal-matching-mesh-to-part-geometry\/\" target=\"_blank\" rel=\"noopener noreferrer\">Ceramic Bead Size Selection Guide<\/a><p>Selecting finer beads is the primary lever for reducing material removal on tight-tolerance parts.<\/p><\/div>\n<div class=\"rel-c\"><a href=\"https:\/\/hlh-js.com\/resource\/blog\/ceramic-bead-blasting-pa12-nylon-sls-parts-depowdering-and-surface-prep\/\" target=\"_blank\" rel=\"noopener noreferrer\">PA12 SLS Depowdering Protocol<\/a><p>PA12-specific protocol with dimensional accuracy data for the most common SLS material.<\/p><\/div>\n<div class=\"rel-c\"><a href=\"https:\/\/hlh-js.com\/resource\/blog\/ceramic-bead-blasting-tpu-flexible-sls-parts-gentle-depowdering-without-deformation\/\" target=\"_blank\" rel=\"noopener noreferrer\">TPU Flexible SLS Depowdering<\/a><p>Dimensional considerations for flexible SLS materials \u2014 deformation vs. material removal.<\/p><\/div>\n<div class=\"rel-c\"><a href=\"https:\/\/hlh-js.com\/resource\/blog\/ceramic-bead-recycling-and-lifespan-management-in-sls-depowdering-operations\/\" target=\"_blank\" rel=\"noopener noreferrer\">Bead Recycling and Lifespan Management<\/a><p>How media charge aging affects material removal rate and when to monitor more closely.<\/p><\/div>\n<\/div>\n<div class=\"cta\"><h3>Need Dimensional Data for Your SLS Ceramic Bead Blasting Protocol?<\/h3>\n<p>Jiangsu Henglihong Technology Co., Ltd. provides ceramic blasting beads with full technical documentation and can advise on bead grade and size selection to meet specific dimensional tolerance requirements. Contact us with your SLS material, part geometry, and tolerance class.<\/p>\n<a href=\"https:\/\/hlh-js.com\/contact\/\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"btn\">Request Technical Support<\/a><\/div>\n<\/article>\n<script>(function(){var b=document.querySelectorAll('.hlh-sls-c08 .fq');b.forEach(function(btn){btn.addEventListener('click',function(){var a=this.nextElementSibling,o=a.classList.contains('open');document.querySelectorAll('.hlh-sls-c08 .fa').forEach(function(x){x.classList.remove('open')});document.querySelectorAll('.hlh-sls-c08 .fq').forEach(function(x){x.classList.remove('open');x.setAttribute('aria-expanded','false')});if(!o){a.classList.add('open');btn.classList.add('open');btn.setAttribute('aria-expanded','true')}})})})();<\/script>","protected":false},"excerpt":{"rendered":"<p>&#8592; Part of: Ceramic Beads for SLS Powder Removal \u2014  [&#8230;]<\/p>","protected":false},"author":1,"featured_media":13870,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[62,175,138],"tags":[],"class_list":["post-13868","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog","category-industry","category-resource"],"_links":{"self":[{"href":"https:\/\/hlh-js.com\/zh\/wp-json\/wp\/v2\/posts\/13868","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/hlh-js.com\/zh\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/hlh-js.com\/zh\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/hlh-js.com\/zh\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/hlh-js.com\/zh\/wp-json\/wp\/v2\/comments?post=13868"}],"version-history":[{"count":2,"href":"https:\/\/hlh-js.com\/zh\/wp-json\/wp\/v2\/posts\/13868\/revisions"}],"predecessor-version":[{"id":13871,"href":"https:\/\/hlh-js.com\/zh\/wp-json\/wp\/v2\/posts\/13868\/revisions\/13871"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/hlh-js.com\/zh\/wp-json\/wp\/v2\/media\/13870"}],"wp:attachment":[{"href":"https:\/\/hlh-js.com\/zh\/wp-json\/wp\/v2\/media?parent=13868"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/hlh-js.com\/zh\/wp-json\/wp\/v2\/categories?post=13868"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/hlh-js.com\/zh\/wp-json\/wp\/v2\/tags?post=13868"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}