Side Viewing Interferometric Probe Alignment for near Vertical Steel Sidewalls
Aligning side-viewing optical probes on vertical steel sidewalls requires tip-tilt control within 0.05 degrees to preserve coherence fringe visibility.
Draft Angle Alignment
Meaning
Geometric calibration of the taper on vertical tool surfaces ensures the clean release of a solidified polymer part from the mold cavity during the ejection phase. For deep-draw containers and housings, draft angle alignment dictates the uniform distribution of the mechanical taper relative to the primary draw axis. Correct taper angles prevent the part walls from dragging against the steel or aluminum faces, which would otherwise scuff the textured surfaces.
Release Efficiency
Precise alignment of these angles is particularly necessary when processing high-shrinkage polymers like polypropylene or polyamide. A mold designer sets the draft angle in the initial CAD model, but the actual draft angle alignment must be verified on the machined steel insert before production. When this value falls below the required threshold, excessive friction generates localized vacuum zones that cause the part to stick.
Ejection Force
High release forces distort the hot polymer part as the ejector pins push against the runner and base. If the molded part is ejected before it has cooled sufficiently, this stress leaves white stress marks or punches through the plastic wall entirely. Regrind polymers with higher friction coefficients aggravate this issue, requiring steeper taper angles to maintain stable cycle times.
Geometric Integrity
Coordinated coordinate measuring machine sweeps trace the vertical profile of the mold cavity to verify the alignment. This precise measurement identifies machining errors from the EDM or milling steps that altered the intended draft angle. The data ensures that the mold operates at optimal speeds without requiring excessive amounts of mold release spray.