{"id":100271,"date":"2026-02-15T20:31:15","date_gmt":"2026-02-15T20:31:15","guid":{"rendered":"https:\/\/vibromera.eu\/?post_type=calculator&#038;p=100271"},"modified":"2026-03-05T15:38:18","modified_gmt":"2026-03-05T15:38:18","slug":"turning-surface-finish","status":"publish","type":"calculator","link":"https:\/\/vibromera.eu\/bn\/calculators\/turning-surface-finish\/","title":{"rendered":"\u099f\u09be\u09b0\u09cd\u09a8\u09bf\u0982 \u09aa\u09c3\u09b7\u09cd\u09a0 \u09b8\u09ae\u09be\u09aa\u09cd\u09a4\u09bf \u0995\u09cd\u09af\u09be\u09b2\u0995\u09c1\u09b2\u09c7\u099f\u09b0 | Ra \u09b8\u09c2\u09a4\u09cd\u09b0 | Vibromera"},"content":{"rendered":"\n<script type=\"application\/ld+json\">\n{\"@context\":\"https:\/\/schema.org\",\"@type\":\"WebApplication\",\"name\":\"Turning Surface Finish Calculator\",\"description\":\"Calculate theoretical surface roughness Ra for turning operations.\",\"url\":\"https:\/\/vibromera.eu\/calculators\/turning-surface-finish\/\",\"applicationCategory\":\"Engineering Calculator\",\"operatingSystem\":\"Any\",\"offers\":{\"@type\":\"Offer\",\"price\":\"0\",\"priceCurrency\":\"EUR\"},\"creator\":{\"@type\":\"Organization\",\"name\":\"Vibromera\",\"url\":\"https:\/\/vibromera.eu\/\"},\"datePublished\":\"2024-01-01\",\"dateModified\":\"2025-02-14\",\"inLanguage\":\"en\",\"isAccessibleForFree\":true}\n<\/script>\n\n<script type=\"application\/ld+json\">\n{\"@context\":\"https:\/\/schema.org\",\"@type\":\"FAQPage\",\"mainEntity\":[\n{\"@type\":\"Question\",\"name\":\"What is the Ra formula for turning?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"The theoretical arithmetic roughness Ra = f\u00b2\/(32\u00d7r), where f is feed per revolution in mm and r is the tool nose radius in mm. Result is in mm; multiply by 1000 for \u03bcm.\"}},\n{\"@type\":\"Question\",\"name\":\"How does feed affect surface finish?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Surface roughness increases with the square of feed. Halving the feed reduces Ra by a factor of 4, making feed the dominant parameter for finish quality.\"}},\n{\"@type\":\"Question\",\"name\":\"How does nose radius affect surface finish?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Larger nose radius produces better surface finish. Doubling the nose radius halves the Ra value. Typical radii range from 0.4 to 1.6 mm.\"}},\n{\"@type\":\"Question\",\"name\":\"Why is actual Ra worse than theoretical?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Real Ra is typically 1.5\u20133\u00d7 theoretical due to vibrations, tool wear, built-up edge, material properties, and machine rigidity. The formula gives the best achievable finish.\"}},\n{\"@type\":\"Question\",\"name\":\"What is a good surface finish for turned parts?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Ra 1.6 \u03bcm is common for general machining. Ra 0.8 \u03bcm for precision fits. Ra 0.4 \u03bcm or better requires fine finishing or grinding.\"}}\n]}\n<\/script>\n\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"BreadcrumbList\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/vibromera.eu\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Calculators\",\"item\":\"https:\/\/vibromera.eu\/calculators\/\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"Turning Surface Finish\",\"item\":\"https:\/\/vibromera.eu\/calculators\/turning-surface-finish\/\"}]}<\/script>\n\n<link rel=\"preconnect\" href=\"https:\/\/fonts.googleapis.com\">\n\n<link rel=\"preconnect\" href=\"https:\/\/fonts.gstatic.com\" crossorigin>\n\n<link 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a:hover{text-decoration:underline}.vc-footer-links{margin-top:8px;font-size:12px}.vc-footer-links a{margin:0 8px}@media print{.vc-section-body{max-height:none!important}.vc-faq-a{max-height:none!important}.vc-results{max-height:none!important;padding:24px!important}.vc-copy-btn,.vc-section-chevron,.vc-faq-chevron,.vc-presets,.vc-promo{display:none!important}}\n<\/style>\n\n<div class=\"vc-calculator\" id=\"vc-surface-finish\">\n<header class=\"vc-header\">\n    <p class=\"vc-header-eyebrow\">Free Engineering Tool #212<\/p>\n    <h1 class=\"vc-header-title\">Turning Surface Finish Calculator<\/h1>\n    <p class=\"vc-header-subtitle\">Calculate theoretical surface roughness Ra for turning. Enter feed per revolution and tool nose radius.<\/p>\n    <div class=\"vc-badges\"><span class=\"vc-badge\">Ra = f\u00b2 \/ (32 \u00d7 r)<\/span><span class=\"vc-badge\">Turning<\/span><span class=\"vc-badge\">Auto-Calc<\/span><\/div>\n<\/header>\n<div class=\"vc-card\">\n    <form class=\"vc-form\" id=\"vc-form\" autocomplete=\"off\">\n        <div class=\"vc-form-grid\">\n            <div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-f\">Feed per Revolution (f) <span class=\"vc-label-hint\">(mm\/rev)<\/span><\/label><input class=\"vc-input\" type=\"number\" id=\"vc-f\" step=\"any\" min=\"0.001\" placeholder=\"e.g. 0.20\" value=\"0.20\"><\/div>\n            <div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-r\">Tool Nose Radius (r) <span class=\"vc-label-hint\">(mm)<\/span><\/label><input class=\"vc-input\" type=\"number\" id=\"vc-r\" step=\"any\" min=\"0.01\" placeholder=\"e.g. 0.8\" value=\"0.8\"><\/div>\n        <\/div>\n        <div class=\"vc-presets\">\n            <div class=\"vc-presets-label\">Quick presets<\/div>\n            <button type=\"button\" class=\"vc-preset-btn\" data-f=\"0.10\" data-r=\"0.4\">Fine f=0.10, r=0.4<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-f=\"0.20\" data-r=\"0.8\">Standard f=0.20, r=0.8<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-f=\"0.30\" data-r=\"1.2\">Rough f=0.30, r=1.2<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-f=\"0.15\" data-r=\"1.6\">Finish f=0.15, r=1.6<\/button>\n        <\/div>\n    <\/form>\n    <div class=\"vc-results\" id=\"vc-results\">\n        <div class=\"vc-results-head\"><h2 class=\"vc-results-title\">Results<\/h2><button type=\"button\" class=\"vc-copy-btn\" id=\"vc-copy-btn\"><svg width=\"14\" height=\"14\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><rect x=\"9\" y=\"9\" width=\"13\" height=\"13\" rx=\"2\"\/><path d=\"M5 15H4a2 2 0 01-2-2V4a2 2 0 012-2h9a2 2 0 012 2v1\"\/><\/svg> Copy<\/button><\/div>\n        <div class=\"vc-result-grid\">\n            <div class=\"vc-rcard vc-rcard-primary\"><div class=\"vc-rcard-label\">Theoretical Ra<\/div><div class=\"vc-rcard-value\" id=\"vc-r-ra\">\u2014<\/div><\/div>\n            <div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Rt (peak-to-valley)<\/div><div class=\"vc-rcard-value\" id=\"vc-r-rt\">\u2014<\/div><\/div>\n            <div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Estimated Actual Ra (\u00d72)<\/div><div class=\"vc-rcard-value\" id=\"vc-r-actual\">\u2014<\/div><\/div>\n        <\/div>\n    <\/div>\n<\/div>\n\n<div class=\"vc-section vc-open\"><button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"true\"><span class=\"vc-section-toggle-text\"><span class=\"vc-section-icon\">\ud83d\udcd8<\/span><span class=\"vc-section-title\">Theory &amp; Formulas<\/span><\/span><svg class=\"vc-section-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button>\n    <div class=\"vc-section-body\"><div class=\"vc-section-inner vc-theory\">\n        <h3>Theoretical Surface Roughness<\/h3>\n        <div class=\"vc-formula-box\" id=\"vc-katex-1\"><\/div>\n        <div class=\"vc-formula-box\" id=\"vc-katex-2\"><\/div>\n        <ul>\n            <li><strong>Ra<\/strong> \u2014 arithmetic average roughness (\u03bcm)<\/li>\n            <li><strong>Rt<\/strong> \u2014 peak-to-valley roughness (\u03bcm)<\/li>\n            <li><strong>f<\/strong> \u2014 feed per revolution (mm\/rev)<\/li>\n            <li><strong>r<\/strong> \u2014 tool nose radius (mm)<\/li>\n        <\/ul>\n        <div class=\"vc-example-box\"><div class=\"vc-example-title\">Example \u2014 Standard turning<\/div>\n            <p><strong>Given:<\/strong> f = 0.20 mm\/rev, r = 0.8 mm<\/p>\n            <p>Ra = 0.20\u00b2 \/ (32 \u00d7 0.8) = 0.04 \/ 25.6 = 0.00156 mm = <strong>1.56 \u03bcm<\/strong><\/p>\n            <p>Rt = 0.20\u00b2 \/ (8 \u00d7 0.8) = 0.04 \/ 6.4 = <strong>6.25 \u03bcm<\/strong><\/p>\n        <\/div>\n    <\/div><\/div>\n<\/div>\n\n<div class=\"vc-section\"><button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\"><span class=\"vc-section-toggle-text\"><span class=\"vc-section-icon\">\ud83d\udd17<\/span><span class=\"vc-section-title\">Related Calculators<\/span><\/span><svg class=\"vc-section-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button>\n    <div class=\"vc-section-body\"><div class=\"vc-section-inner\"><div class=\"vc-related\"><a class=\"vc-related-link\" href=\"\/calculators\/cutting-speed-rpm\/\">Cutting Speed \u2194 RPM<\/a><a class=\"vc-related-link\" href=\"\/calculators\/feed-rate-calculator\/\">Feed Rate<\/a><a class=\"vc-related-link\" href=\"\/calculators\/machining-time-calculator\/\">Machining Time<\/a><\/div><\/div><\/div>\n<\/div>\n\n<div class=\"vc-section\"><button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\"><span class=\"vc-section-toggle-text\"><span class=\"vc-section-icon\">\u2753<\/span><span class=\"vc-section-title\">Frequently Asked Questions<\/span><\/span><svg class=\"vc-section-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button>\n    <div class=\"vc-section-body\"><div class=\"vc-section-inner\"><div class=\"vc-faq-list\" id=\"vc-faq-list\"><\/div><\/div><\/div>\n<\/div>\n\n<div class=\"vc-promo\"><div class=\"vc-promo-text\"><strong>Vibromera \u2014 Portable Balancing &amp; Vibration Analysis<\/strong><br>Professional instruments for industrial applications.<\/div><a class=\"vc-promo-link\" href=\"https:\/\/vibromera.eu\/\" target=\"_blank\" rel=\"noopener\">Learn More<\/a><\/div>\n<footer class=\"vc-footer\"><p>\u00a9 2024\u20132025 <a href=\"https:\/\/vibromera.eu\/\">Vibromera<\/a> \u2014 Engineering Calculators<\/p><div class=\"vc-footer-links\"><a href=\"\/calculators\/engineering-calculators\/\">All Calculators<\/a><a href=\"https:\/\/vibromera.eu\/contacts\/\">Contact<\/a><\/div><\/footer>\n<\/div>\n<script src=\"https:\/\/cdn.jsdelivr.net\/npm\/katex@0.16.11\/dist\/katex.min.js\"><\/script>\n<script>\n(function(){\n    'use strict';\n    function $(id){return document.getElementById(id)}\n    function fmt(n,d){if(isNaN(n))return'\u2014';var f=n.toFixed(d===undefined?2:d);return f.replace(\/(\\.\\d*?)0+$\/,'$1').replace(\/\\.$\/,'')}\n    function calculate(){\n        var f=parseFloat($('vc-f').value),r=parseFloat($('vc-r').value);\n        if(!f||f<=0||!r||r<=0){$('vc-results').classList.remove('vc-visible');return}\n        var Ra_mm=f*f\/(32*r);var Ra_um=Ra_mm*1000;\n        var Rt_mm=f*f\/(8*r);var Rt_um=Rt_mm*1000;\n        $('vc-r-ra').innerHTML=fmt(Ra_um,2)+' <span class=\"vc-rcard-unit\">\u03bcm<\/span>';\n        $('vc-r-rt').innerHTML=fmt(Rt_um,2)+' <span class=\"vc-rcard-unit\">\u03bcm<\/span>';\n        $('vc-r-actual').innerHTML='~'+fmt(Ra_um*2,2)+' <span class=\"vc-rcard-unit\">\u03bcm<\/span>';\n        $('vc-results').classList.add('vc-visible');\n    }\n    document.querySelectorAll('.vc-preset-btn').forEach(function(b){b.addEventListener('click',function(e){e.preventDefault();$('vc-f').value=this.dataset.f;$('vc-r').value=this.dataset.r;calculate()})});\n    $('vc-form').addEventListener('input',calculate);$('vc-form').addEventListener('change',calculate);\n    $('vc-copy-btn').addEventListener('click',function(){var t='Surface Finish\\nRa: '+$('vc-r-ra').textContent+'\\nRt: '+$('vc-r-rt').textContent;if(navigator.clipboard)navigator.clipboard.writeText(t)});\n    document.querySelectorAll('.vc-section-toggle').forEach(function(b){b.addEventListener('click',function(){var s=this.closest('.vc-section');s.classList.toggle('vc-open');this.setAttribute('aria-expanded',s.classList.contains('vc-open'))})});\n    var faqData=[\n        {q:'What is the Ra formula for turning?',a:'<p>Ra = f\u00b2\/(32\u00d7r), where f is feed per revolution (mm) and r is tool nose radius (mm). Result in mm; multiply by 1000 for \u03bcm.<\/p>'},\n        {q:'How does feed affect surface finish?',a:'<p>Ra increases with the square of feed. Halving feed reduces Ra by a factor of 4.<\/p>'},\n        {q:'How does nose radius affect surface finish?',a:'<p>Larger nose radius gives better finish. Doubling nose radius halves Ra. Typical radii: 0.4\u20131.6 mm.<\/p>'},\n        {q:'Why is actual Ra worse than theoretical?',a:'<p>Real Ra is typically 1.5\u20133\u00d7 theoretical due to vibrations, tool wear, built-up edge, and material properties.<\/p>'},\n        {q:'What is a good surface finish for turned parts?',a:'<p>Ra 1.6 \u03bcm for general machining. Ra 0.8 \u03bcm for precision fits. Ra 0.4 \u03bcm or better requires fine finishing or grinding.<\/p>'}\n    ];\n    var fl=$('vc-faq-list');faqData.forEach(function(f){fl.innerHTML+='<div class=\"vc-faq-item\"><button type=\"button\" class=\"vc-faq-q\"><span>'+f.q+'<\/span><svg class=\"vc-faq-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button><div class=\"vc-faq-a\"><div class=\"vc-faq-a-inner\">'+f.a+'<\/div><\/div><\/div>'});\n    fl.addEventListener('click',function(e){var b=e.target.closest('.vc-faq-q');if(b)b.closest('.vc-faq-item').classList.toggle('vc-open')});\n    function renderFormulas(){try{\n        katex.render('R_a = \\\\frac{f^2}{32 \\\\times r} \\\\quad [\\\\text{mm} \\\\to \\\\mu m]',$('vc-katex-1'),{displayMode:true,throwOnError:false});\n        katex.render('R_t = \\\\frac{f^2}{8 \\\\times r} \\\\quad [\\\\text{mm} \\\\to \\\\mu m]',$('vc-katex-2'),{displayMode:true,throwOnError:false});\n    }catch(e){}}\n    function init(){renderFormulas();calculate()}\n    if(document.readyState==='loading')document.addEventListener('DOMContentLoaded',init);else init();\n})();\n<\/script>\n","protected":false},"excerpt":{"rendered":"<p>\u09ac\u09be\u09b0\u09cd\u09a8\u09bf\u0982 \u098f\u09b0 \u099c\u09a8\u09cd\u09af \u09ac\u09bf\u09a8\u09be\u09ae\u09c2\u09b2\u09cd\u09af\u09c7 \u09aa\u09c3\u09b7\u09cd\u09a0 \u09b0\u09c1\u0995\u09cd\u09b7\u09a4\u09be \u0995\u09cd\u09af\u09be\u09b2\u0995\u09c1\u09b2\u09c7\u099f\u09b0\u0964 Ra = f\u00b2\/(32r)\u0964 \u09a4\u09be\u09a4\u09cd\u09a4\u09cd\u09ac\u09bf\u0995 \u09aa\u09c3\u09b7\u09cd\u09a0 \u09ab\u09bf\u09a8\u09bf\u09b6 Ra \u0997\u09a3\u09a8\u09be \u0995\u09b0\u09be\u09b0 \u099c\u09a8\u09cd\u09af \u09aa\u09cd\u09b0\u09a4\u09bf \u09ac\u09bf\u09aa\u09cd\u09b2\u09ac\u09c7 \u09ab\u09bf\u09a1 \u098f\u09ac\u0982 \u099f\u09c1\u09b2 \u09a8\u09cb\u099c \u09ac\u09cd\u09af\u09be\u09b8\u09be\u09b0\u09cd\u09a7 \u09b2\u09bf\u0996\u09c1\u09a8\u0964<\/p>","protected":false},"featured_media":0,"template":"","meta":{"ai_generated_summary":"","footnotes":""},"categories":[],"tags":[],"class_list":["post-100271","calculator","type-calculator","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator\/100271","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator"}],"about":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/types\/calculator"}],"version-history":[{"count":2,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator\/100271\/revisions"}],"predecessor-version":[{"id":100753,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator\/100271\/revisions\/100753"}],"wp:attachment":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/media?parent=100271"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/categories?post=100271"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/tags?post=100271"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}