Technical Knowledge Center
From drawings and tolerances to broken spare parts and 3D scanning, these guides cover the questions that tend to block a project before production. The aim is practical decisions, not a glossary.
After CNC and laser cutting
Assess anodising, zinc, heat treatment, polishing, paint, chrome, sheet-metal follow-on work and inspection within one production route.
01 / Technical guides
This guide gives a general technical framework. Final process, tolerance and inspection decisions are confirmed against the actual part.
A 3-axis machine cuts along three linear axes, while a 4th axis can rotate the part to access additional faces with fewer setups. Geometry and tolerance relationships decide which approach is appropriate.
Read the guideBurrs can result from tool condition, cutting parameters, material behavior and edge geometry. The right tooling/process and controlled deburring strategy can reduce them.
Read the guideA fixture locates and holds the part in a defined, repeatable position. Volume, geometry, setup time, rigidity and critical datum relationships determine whether a dedicated fixture is worthwhile.
Read the guideThin walls are sensitive to cutting force, clamping stress and heat; wall thickness, workholding and operation sequence must be considered together.
Read the guide3D scanning is a data-capture method; reverse engineering is the broader process that turns measurements into a manufacturable model with function, dimensions, tolerances and design intent.
Read the guideYes. A physical sample can be converted into digital manufacturing data through conventional measurement, 3D scanning or both; damaged areas should be reconstructed from function and mating geometry rather than copied blindly.
Read the guideNo. The original may be worn, reflect old manufacturing constraints or contain a known weak point. Function and interfaces should be preserved while manufacturing details are reviewed intelligently.
Read the guideYes. The sample, its function in the machine and its interfaces can be reverse engineered; the key is to avoid reproducing years of wear in the new component.
Read the guideThe sample is measured, optionally digitized through a 3D-scanning partner, converted into manufacturable CAD/technical data, assigned material and critical requirements, then matched to the appropriate CNC process.
Read the guideThe process starts by understanding the physical part, then uses measurement and/or 3D scanning, CAD reconstruction, critical-feature verification and manufacturability review to create production data.
Read the guideThe physical surface is scanned, the mesh is cleaned, and a parametric or surface-based CAD model is rebuilt for the intended manufacturing use. Critical dimensions should be independently verified rather than trusted to mesh alone.
Read the guide3D scanning converts a physical surface into dense point/mesh data. It is useful for undocumented, complex or freeform parts; Gizmak can coordinate this step through specialist solution partners when required.
Read the guideOften, yes. Symmetry, intact regions, mating parts, assembly relationships and function can be used to reconstruct the intended nominal geometry instead of reproducing worn or broken surfaces.
Read the guideA clear 3D model, polymer, surface expectations, annual volume, critical dimensions and mold operating targets make both mold design and quotation substantially more reliable.
Read the guideScanner headline accuracy alone is not enough to decide. Part size, surface condition, scanning method and critical tolerances must be considered; very tight features may need independent CMM or other verification.
Read the guide3D scanning is strong at collecting broad surface geometry quickly, while CMM is strong at traceable verification of defined features. On many projects they are complementary rather than competing methods.
Read the guideA CMM fixture holds the part stably in the intended datum relationship while preserving probe access. Poor fixturing can compromise the result of an otherwise good CMM program.
Read the guideAn out-of-tolerance result rarely has one cause: workholding, tool wear, thermal effects, material stress, datum definition and even the measurement method can contribute. Start by identifying the pattern of error.
Read the guideA tolerance defines the acceptable variation of a dimension. Unnecessarily tight tolerances can mean slower machining, more inspection, extra operations and a higher scrap risk.
Read the guideA datum defines the reference framework for making and checking the part; poor selection can make a well-machined part hard to measure or hard to assemble.
Read the guideFirst article inspection verifies that drawing interpretation, process selection and inspection logic are aligned before serial production starts.
Read the guideFit codes describe hole and shaft tolerance zones; the correct choice depends on assembly method, desired clearance/interference and process capability.
Read the guideAlthough they look similar, flatness controls form of a single surface while parallelism and perpendicularity control orientation between features; choosing the wrong one can add cost or confusion.
Read the guideNot every job needs a full CMM report; critical dimensions, datum structure, customer expectation and traceability define the required report depth.
Read the guideISO 2768-1, ISO 22081 and ISO 286 address different needs: general size tolerances, general geometrical specifications and hole/shaft fits. Check the edition and drawing-specific requirements before quoting.
Read the guideThese documents are not identical; the right level of traceability and conformity depends on the application.
Read the guideRa expresses average surface roughness. The lowest Ra is not automatically best; sealing, bearing, friction, coating requirements and cost should be considered together.
Read the guideIn an assembly, variation accumulates across multiple parts; that is why individually acceptable parts can still create a functional problem together.
Read the guideTrue position controls where features should be relative to datums and is often more robust than controlling hole patterns with only ± dimensions.
Read the guideNo. CMM inspection is especially valuable for geometric tolerances, linked critical features and traceable reporting; simpler dimensions may be verified more efficiently with other suitable instruments.
Read the guideHole type should be chosen not by drawing habit but by function, tool access, chip evacuation and tolerance needs.
Read the guideWhen available, a STEP model plus a revision-controlled PDF drawing is usually the strongest starting point. DXF/DWG suit 2D profiles, while STL is mesh-based and may not communicate all manufacturing intent on its own.
Read the guideA truly sharp internal corner is not realistic in CNC machining because the cutter has a diameter; the inside radius should be chosen around tool access, strength and function.
Read the guideA mesh is not automatically a clean STEP model. Manufacturable CAD normally requires rebuilding relevant surfaces and features, then defining critical dimensions from design intent.
Read the guideAt minimum, dimensions, tolerances, datums, material, surface/roughness requirements, special processes and revision status should be clear. Pairing 3D CAD with a controlled drawing significantly reduces ambiguity.
Read the guideUnnecessarily difficult thread depths and blind-hole choices increase tool risk and cost; standard series and practical depths should be preferred.
Read the guideGeometry with an undercut or no standard tool access may require special tooling or another process; the choice depends on function and quantity.
Read the guideAlloy choice should consider not only strength but also machinability, corrosion behaviour, welding needs, finishing and cost.
Read the guideAnodizing grows an oxide layer on the surface; fits, threads and sealing surfaces may need pre- and post-finish dimensional planning.
Read the guideMaterial choice is not simply a question of maximum strength. Load, weight, corrosion, temperature, friction, machinability and cost need to be balanced against the part’s function.
Read the guideChoosing an engineering plastic is not only about stiffness; friction, moisture, temperature, chemicals and dimensional stability all matter.
Read the guideCoating thickness, thermal stress change and any post-process correction can alter dimensions, so critical tolerances must be planned together with the process chain.
Read the guideThe 304-versus-316 decision is usually about corrosion environment, cost and machinability; the two grades are not interchangeable in every application.
Read the guideSurface finishing is not just a cosmetic choice; corrosion, friction, conductivity, contact surfaces and tolerance impact all need to be considered.
Read the guidePrice is shaped by programming/setup, number of setups, machining time, tooling, tolerance, finishing, inspection and quantity as well as raw material. Two parts of the same weight can therefore have very different costs.
Read the guideDeep pockets and narrow slots make tool access harder, increase chatter risk and lengthen machining time; proportions and radii should be adjusted for manufacturability where possible.
Read the guideThe biggest savings often come not from cheaper material but from removing unnecessarily tight tolerances, difficult tool access, excess setups, deep features and special operations.
Read the guideChoosing the right CNC supplier is not only about price comparison; technical communication, risk management, quality logic and process fit all matter.
Read the guideIn one-off work, programming and setup are carried by a single part; in series work those costs are spread, while dedicated fixturing, process stability and repeatable inspection become more important.
Read the guideA prototype may primarily validate the design; series production shifts the focus toward repeatability, workholding, cycle time, inspection planning, material supply and unit cost.
Read the guideEvery extra setup adds time and datum-transfer risk; sometimes multiple setups are necessary, but reducing them can improve repeatability.
Read the guidePrice gaps often come not only from margin but from different process assumptions, tolerance interpretation, inspection depth, material sourcing and delivery logic.
Read the guide08 / Enquiry
Use the guide as a starting point, then share the actual technical data or physical sample so the manufacturing route can be reviewed against the real project.
