Controlling full-length accuracy on a 6 m structure

The accuracy on a long part is won before cutting starts. When three segments are machined separately and welded, each weld cycle adds distortion that has to be corrected by re-machining, and the cumulative tolerance budget is largely spent on the joints. A single-setup pass on a 6 m gantry removes the joints entirely — the tolerance becomes available for the features that matter.

Thermal behavior is the other half: roughing with a cool-down interval before finishing, in a temperature-monitored environment, keeps the part from drifting as it warms. Full-length inspection reports the actual numbers along the length.

Deep-hole drilling: chip evacuation and straightness

Deep holes fail in predictable ways — chip packing bends the drill and the hole wanders. The fix is rarely a better tool; it is peck cycle timing, coolant delivery at the cutting edge, and verifying straightness against a true reference rather than the hole wall. For critical bores we confirm on CMM rather than trusting the drill.

Preventing deflection and residual stress in thin-wall parts

Thin-wall parts that measure fine off the machine and then move are almost always a clamping or stress problem, not a tolerance problem. Sequencing the cut so the part is supported where it is being cut, and relieving residual stress before the finishing pass, is what keeps the part inside tolerance after it leaves the fixture.

Sink marks: diagnosing pack-pressure vs. mold steel

A visible sink near a rib is often read as “the mold is wrong” and answered with an expensive rebuild. Short-shot and pressure studies usually show it is a cooling and pack-pressure profile problem — the gate freezes before the thick section is packed out. Adjusting the packing profile and wall thickness in non-functional areas fixes the sink and cuts shot weight, with no new mold.