As the geometric reference carrier for ultra‑precision equipment, the final flatness, surface quality, dimensional consistency and accuracy retention of finished granite bases cannot be achieved merely by high‑quality raw blocks. The complete grinding workflow consisting of rough grinding and fine grinding serves as the core manufacturing link that converts material potential into high‑performance bases. Many people simply regard grinding as "smoothing surfaces". In fact, rough grinding and fine grinding have clear‑cut responsibilities: removing machining allowances, releasing processing stress, correcting geometric profiles and delivering nano‑level surface quality. Drawing on full‑process experience in granite component manufacturing, UNPARALLELED Group strictly differentiates process parameters for rough grinding, transitional grinding and fine grinding. Material removal and accuracy iteration are completed in graded phases to build solid technological foundations for the comprehensive performance of finished granite bases.
Rough grinding is the first critical grinding procedure for granite bases. Its primary task is to rapidly remove milling tool marks and uneven allowances, and correct major geometric deviations inherited from blanks. After cutting and rough milling, granite workpieces carry cutting traces and local height differences. Meanwhile, rough milling leaves residual cutting stress within the stone surface layer. If proceeding directly to finishing, gradual stress release will trigger accuracy drift during service. In rough‑grinding phase, coarse‑grain abrasives are adopted for uniform grinding. It not only removes machining allowances efficiently, but also eliminates damaged layers induced by milling and relieves residual surface cutting stress. The overall geometric profile of workpieces is corrected close to target dimensions, leaving reasonable and uniform stock for subsequent fine grinding. High surface finish is not pursued in rough grinding. Instead, preliminary corrections are implemented for overall parallelism and basic plane contours. Excessive profile deviation in rough grinding can hardly be compensated in later fine grinding and may directly lead to finished‑product rejection.
Workpieces will not go straight to top‑grade fine grinding upon rough‑grinding completion. Transitional grinding is arranged in‑between with progressively finer abrasives to realize a gentle transition of grinding force. Granite is brittle mineral material. Excessive jump in abrasive grain size will produce invisible micro‑chipping and micro‑cracks on workpiece surfaces. Such microscopic defects will expand gradually under vibration and alternating temperature and damage guide‑rail mounting datums. Graded transitional grinding removes grinding‑induced damaged layers from previous passes layer by layer, continuously releases newly‑generated grinding stress and optimizes plane profiles. Geometric errors are further narrowed so that workpieces entering fine grinding feature uniform allowances and stable substrate conditions, lowering processing loads for fine grinding.
Fine grinding determines the final geometric accuracy and surface quality of granite bases. All operations must be carried out in constant‑temperature workshops to avoid thermal deformation caused by temperature fluctuation. Fine grinding removes material in tiny increments to make high‑precision corrections for flatness, parallelism, hole‑end faces and guide‑rail mounting datums and achieves nano‑level planar accuracy. Unlike rough grinding for bulk material removal, fine grinding focuses on correcting geometric errors, optimizing surface micro‑morphology and eliminating waviness. It guarantees unified and continuous geometric status for all mounting datums on the base. Micro‑surface quality of guide‑rail mounting faces and positioning datums directly affects fitting conditions for linear motors and guide‑rail modules. Dense and uniform surfaces after fine grinding ensure sufficient assembly contact and prevent deformation errors caused by partial poor fitting during equipment operation.
Reasonable rough‑and‑fine‑grinding procedures also contribute to long‑term geometric stability of granite bases. If manufacturers prioritize efficiency by simplifying rough grinding and skipping damaged‑layer removal and only rely on fine grinding for surface polishing, substantial processing stress and micro‑cracks will be buried inside surface layers. Although short‑term inspection results can meet specifications, gradual stress release and micro‑crack propagation during long‑term service will cause slow plane deformation and accuracy loss. UNPARALLELED Group implements stress control throughout the whole grinding workflow: rough grinding removes allowances and surface damages, graded grinding releases stress, and fine grinding finalizes precision shaping. Full‑item inspections covering flatness, parallelism, perpendicularity and hole dimensions are conducted after grinding. Test instruments are CNAS‑calibrated with fully traceable test data. Products comply with ISO three‑system and CE requirements.
Completion of grinding does not mark the end of machining. Full visual inspection is implemented afterwards to check edge chipping and surface micro‑defects before protective treatment. Rough grinding shapes profiles and eliminates damages; fine grinding defines final accuracy and references. Both procedures connect closely and neither can be neglected. In semiconductor equipment, optical inspection and precision measuring instrument industries, customers demand not only satisfactory factory‑outlet indicators but also multi‑year accuracy retention. A well‑controlled rough‑fine grinding workflow delivers more than qualified inspection data. It mitigates internal hidden risks induced by grinding from the process perspective. Therefore, granite bases sustain stable geometric status of reference faces under industrial conditions with continuous loads, vibration interference and alternating temperature, delivering reliable base support for various ultra‑precision equipment.