Show the part from its datum axis
Custom CNC turning parts are commonly specified by features arranged around a rotational axis. Identify the datum axis and show the functional diameters, overall length, shoulders, and end faces that locate the part in an assembly. Include the part number, revision, material, quantity, and units.
Call out threads, grooves, and transitions
Use complete thread callouts and show groove dimensions, reliefs, chamfers, and radii that affect mating or assembly. Mark which features are functional and identify any required runout or concentricity control from the design.
Especifique o acabamento e a inspeção
State the required surface finish and any secondary treatment, including which surfaces are affected. Identify critical dimensions and how they should be measured. List reports or material records required by the purchase scope.
Review the drawing and model together
Check that the model matches the drawing and that dimensions, units, and revisions agree. If a mating part determines clearance or fit, provide its controlled interface information or assembly reference.
Compare the turning scope
Request comparable quotes for the same material, quantity, features, finish, inspection, and delivery terms. Ask suppliers to list included secondary operations and any exclusions.
