{"id":3192,"date":"2026-07-29T10:41:59","date_gmt":"2026-07-29T02:41:59","guid":{"rendered":"https:\/\/jtlcnc.com\/?p=3192"},"modified":"2026-07-29T10:42:02","modified_gmt":"2026-07-29T02:42:02","slug":"do-not-replace-manual-grinding-with-machines-00-level-precision-is-achieved","status":"publish","type":"post","link":"https:\/\/jtlcnc.com\/ru\/2026\/07\/29\/do-not-replace-manual-grinding-with-machines-00-level-precision-is-achieved\/","title":{"rendered":"Do not replace manual grinding with machines; 00-level precision is achieved"},"content":{"rendered":"

Not replacing manual grinding with machines: Process deconstruction of achieving standard precision for Grade 00 granite inspection platforms<\/p>\n\n\n\n

Introduction
CNC grinders and surface grinding equipment can complete the basic surface processing of granite platforms, but the machine tool’s own guide rail errors and inherent motion trajectory deviations cannot be completely eliminated; relying solely on mechanical grinding will leave periodic machining patterns on the platform’s microscopic surface, making it difficult to meet the continuous contact precision of Grade 00.
To stably achieve the Grade 00 precision of the GB\/T20428 standard, the process route of mechanical rough grinding as a base followed by manual scraping and matching grinding as the final core process is irreplaceable. Manual grinding is not about replacing equipment, but about using manual labor to correct the residual systematic errors of mechanical processing to achieve a uniformly flat surface datum across the entire area.<\/p>\n\n\n\n

I. Distinction between the precision boundaries of mechanical grinding and manual grinding
Positioning of CNC water grinding process: Semi-finishing
The machine tool is responsible for removing most of the excess material to achieve the general surface profile, converging the surface error to the 8~12\u03bcm range.
Limitations: The reciprocating motion of the grinding disc forms regular ripples, with microscopic highs and lows; the grinding pressure is uneven at the ends and corners of long platforms, causing edge collapse, which cannot be eliminated by the machine tool alone.
Positioning of manual scraping \/ matching grinding: Final finishing (Core)
Goal: Eliminate machining ripples, correct corner collapses, balance the overall flatness, compress the total error within the national standard Grade 00 tolerance range, and optimize the microscopic surface contact quality.
Core logic: Mechanical equipment ensures efficiency, while manual grinding is responsible for correcting systematic errors; relying entirely on machines makes it difficult to stably produce Grade 00 platforms that meet metrological requirements.<\/p>\n\n\n\n

II. Complete process flow for achieving Grade 00 without fully automatic final grinding, relying on manual grinding
Process 1: Blank rough processing multi-stage aging (preliminary foundation)
Select dense Jinan Qinghui long granite blanks, saw-cut and mill the shape; let the rough-processed blank rest for natural aging for \u22653 months to release internal stresses from mining and cutting.
After rough grinding, perform semi-finishing again, and let it rest a second time for 15~30 days to avoid later precision rebound. If aging is insufficient, the precision cannot be locked in long-term, regardless of whether it is mechanical or manual grinding.
Process 2: CNC water grinding semi-finishing
Complete mechanical grinding in a constant temperature workshop (20\u00b12\u2103) to uniformly remove the machining allowance; control the surface roughness of the working surface to Ra\u22640.2\u03bcm after processing.
Termination standard: Control the overall surface error to \u226410\u03bcm, reserving a 3~6\u03bcm allowance for manual correction; do not over-rely on the machine tool to pursue high precision, otherwise the manual grinding allowance will be insufficient to eliminate the machine tool’s machining patterns.
Process 3: Manual matching grinding (Key process, no fully automatic grinding equipment used)
Requirements for the reference plate
Prepare a metrologically calibrated standard granite reference plate in advance to serve as the reference master plate for manual matching grinding, with a reference plate precision no lower than Grade 000.
Operational specifications for manual matching grinding
In a constant temperature dust-free environment, evenly spread extremely fine silicon carbide grinding sand and lubricate with pure water; the technician manually pushes and grinds the workpiece platform using a cross-reciprocating, diagonal-changing trajectory.
Clean the surface after each round of matching grinding, and use the blue oil spotting method to observe the distribution of contact spots:
\u2705 Preconditions for Grade 00 compliance: Contact spots are uniformly distributed across the entire working surface, with \u226520 contact spots within a 25mm\u00d725mm area, no large blank areas, and no locally dense areas.
Continuously perform slight manual correction on sparse spot areas, step by step<\/p>\n\n\n\n

Process 4: Fine Manual Scraping and Polishing (Correcting Local Errors)
To address issues such as central bulging and end sinking commonly occurring in long bases and large platforms, manual scraping is used to remove high spots in minute amounts.
Manual Advantage: Skilled technicians can perform point-specific, minute adjustments to local areas based on level detector data; large-scale automated grinding equipment struggles to achieve such differentiated local fine-tuning.
Process 5: Cleaning, Constant Temperature Soaking, and Isothermal Treatment
After manual grinding is completed, all grinding abrasive particles are thoroughly cleaned to prevent residual particles from scratching the reference surface. The platform is placed in a constant temperature workshop for 24 hours of isothermal soaking to eliminate surface temperature stresses generated during grinding, and the final inspection is carried out after the dimensions stabilize.
Process 6: Full Project Metrological Inspection (Free Support Inspection)
A three-point free support method is adopted, using a precision autocollimator and an electronic level to continuously sample and map the flatness; the full-length diagonal flatness error is calculated according to GB\/T20428 to confirm it meets the Grade 00 tolerance standard; surface roughness and appearance defects are simultaneously inspected.<\/p>\n\n\n\n

III. Core Advantages of Manual Grinding in Achieving Grade 00 Precision (Irreproducible by Machines)
Eliminating Systematic Machine Tool Trajectory Errors
Any grinding machine’s grinding plate and guide rails possess inherent minute linear errors, which permanently replicate as machining patterns on the workpiece surface; manual random variation of the pushing trajectory breaks periodic ripples, achieving a continuous smooth microscopic plane. This effect is particularly pronounced for the specialized long granite bases of linear motors.
Flexible Correction of Irregular Errors
Long platforms, platforms with holes, and thickened gantry crossbeams are extremely prone to edge collapse due to uneven force distribution during mechanical grinding; manual grinding allows targeted control of edge pressure to balance the planar precision of the entire plate.
Superior Microscopic Surface Quality
The reference surface after manual matching has uniform microscopic peaks and valleys. In the use of linear motor modules and inspection tooling, the guide rail bottom fits tightly, and local micro-deformation is unlikely to occur after tightening, ensuring long-term stability of micron-level positioning. Purely mechanically ground plate surfaces are prone to local false contact.
IV. Process Difficulties and Quality Control Red Lines (Avoiding Precision Failure in Manual Grinding)
Strict Environmental Requirements
Manual grinding must be carried out entirely in a constant-temperature workshop; outdoor operations or workshops with large temperature fluctuations are prohibited. If the temperature fluctuation exceeds 3\u00b0C, the dimensional precision of manual grinding loses its reference value.
Technician Skill Threshold
Manual grinding of Grade 00 platforms is a highly skilled job; novices easily cause “over-grinding depressions and local preferential grinding.” It requires long-term practical experience to control the grinding amount, keeping the single-pass removal amount at the sub-micron level.
Eliminating Over-grinding
Continuous long-term concentrated manual grinding of a single area will cause local sinking, directly leading to flatness exceeding standards. The principle of “small amounts multiple times, full-area balance” must be followed.
Grinding Consumable Control
The grit size of the grinding abrasive decreases step by step, with coarse sand for shaping and fine sand for polishing; mixing coarse and fine sand is strictly prohibited to prevent hard coarse particles from forming deep scratches on the plate surface.
V. Extended Application Scenarios
The Grade 00 granite platforms produced by this “Mechanical Rough Grinding Manual Final Grinding” process are particularly suitable for:
\u2705 Micron-level positioning bases for linear motors, optical inspection platforms, and CMM auxiliary worktables;
\u2705 High-end precision equipment where customers require high reference surface contact precision, long-term precision stability, and rejection of machining patterns.
VI. Summary
Automated grinding equipment can achieve basic mass-production precision, but to stably produce compliant Grade 00 granite reference platforms, the manual matching and scraping processes cannot be simply replaced. Mechanical grinding completes the contour processing, while manual grinding eliminates inherent equipment errors and optimizes full-area planar uniformity.
Without relying on fully automated final grinding equipment, through a complete closed-loop process of multi-stage aging, machine tool pre-processing, constant-temperature manual plate matching, spot-method quality control, and isothermal post-inspection, it is entirely possible to stably achieve the national standard Grade 00 planar precision. This yields a continuous uniform reference plane that is difficult to achieve through mechanical grinding, supporting micron-level ultra-precision positioning and metrological inspection requirements.<\/p>\n\n\n\n

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Not replacing manual grinding with machines: Process deconstruction of achieving standard precision for Grade 00 granite inspection platforms IntroductionCNC grinders and surface grinding equipment can complete the basic surface processing of granite platforms, but the machine tool’s own guide rail errors and inherent motion trajectory deviations cannot be completely eliminated; relying solely on mechanical grinding…<\/p>","protected":false},"author":1,"featured_media":3193,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_seopress_titles_title":"","_seopress_titles_desc":"","_seopress_robots_index":"","_seopress_robots_follow":"","_seopress_robots_imageindex":"","_seopress_robots_snippet":"","_seopress_robots_primary_cat":"","_seopress_robots_breadcrumbs":"","_seopress_robots_freeze_modified_date":"","_seopress_robots_custom_modified_date":"","_seopress_robots_canonical":"","_seopress_social_fb_title":"","_seopress_social_fb_desc":"","_seopress_social_fb_img":"","_seopress_social_fb_img_attachment_id":0,"_seopress_social_fb_img_width":0,"_seopress_social_fb_img_height":0,"_seopress_social_twitter_title":"","_seopress_social_twitter_desc":"","_seopress_social_twitter_img":"","_seopress_social_twitter_img_attachment_id":0,"_seopress_social_twitter_img_width":0,"_seopress_social_twitter_img_height":0,"_seopress_redirections_value":"","_seopress_redirections_enabled":"","_seopress_redirections_enabled_regex":"","_seopress_redirections_logged_status":"","_seopress_redirections_param":"","_seopress_redirections_type":0,"_seopress_analysis_target_kw":"","_kad_blocks_custom_css":"","_kad_blocks_head_custom_js":"","_kad_blocks_body_custom_js":"","_kad_blocks_footer_custom_js":"","_kadence_starter_templates_imported_post":false,"_kad_post_transparent":"","_kad_post_title":"","_kad_post_layout":"","_kad_post_sidebar_id":"","_kad_post_content_style":"","_kad_post_vertical_padding":"","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"_kad_post_classname":"","footnotes":""},"categories":[35],"tags":[],"class_list":["post-3192","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news"],"taxonomy_info":{"category":[{"value":35,"label":"NEWS"}]},"featured_image_src_large":["https:\/\/jtlcnc.com\/wp-content\/uploads\/2026\/07\/\u5fae\u4fe1\u56fe\u7247_20260725103811_106_25.png",844,794,false],"author_info":{"display_name":"jinxing6611@gmail.com","author_link":"https:\/\/jtlcnc.com\/ru\/author\/jtlcnc\/"},"comment_info":0,"category_info":[{"term_id":35,"name":"NEWS","slug":"news","term_group":0,"term_taxonomy_id":35,"taxonomy":"category","description":"","parent":0,"count":311,"filter":"raw","cat_ID":35,"category_count":311,"category_description":"","cat_name":"NEWS","category_nicename":"news","category_parent":0}],"tag_info":false,"_links":{"self":[{"href":"https:\/\/jtlcnc.com\/ru\/wp-json\/wp\/v2\/posts\/3192","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/jtlcnc.com\/ru\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/jtlcnc.com\/ru\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/jtlcnc.com\/ru\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/jtlcnc.com\/ru\/wp-json\/wp\/v2\/comments?post=3192"}],"version-history":[{"count":1,"href":"https:\/\/jtlcnc.com\/ru\/wp-json\/wp\/v2\/posts\/3192\/revisions"}],"predecessor-version":[{"id":3194,"href":"https:\/\/jtlcnc.com\/ru\/wp-json\/wp\/v2\/posts\/3192\/revisions\/3194"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/jtlcnc.com\/ru\/wp-json\/wp\/v2\/media\/3193"}],"wp:attachment":[{"href":"https:\/\/jtlcnc.com\/ru\/wp-json\/wp\/v2\/media?parent=3192"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/jtlcnc.com\/ru\/wp-json\/wp\/v2\/categories?post=3192"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/jtlcnc.com\/ru\/wp-json\/wp\/v2\/tags?post=3192"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}