Hot cracking—also known as solidification cracking—occurs during the cooling phase of a weld or thermal cut. While it is a well-known phenomenon in welding, it also frequently plagues CNC cutting operations. SheetCam, a premier CAM software for plasma, oxy-fuel, waterjet, and laser cutting, provides advanced tools to mitigate this issue.
If the sheet is clamped too rigidly or the part geometry prevents natural expansion and contraction, stress accumulates directly in the weld/cut zone.
Check your CNC controller software (such as Mach3, Mach4, or LinuxCNC). Ensure that the post-processor you use in SheetCam properly syncs the torch-off signal with the motion commands so the torch doesn't pause prematurely. sheetcam hot crack
Hot cracking is caused by the complex interplay of high temperatures and tensile stress. weldingengineers.co.nz Rapid Cooling:
If you use SheetCam for plasma or laser cutting, you’ve likely experienced the frustration of a "hot crack." You load your DXF file, generate your toolpath, and everything looks good—until the machine actually starts cutting. Suddenly, the torch lingers too long in one spot, or the cut path logic seems to "break," resulting in a blown-out corner or a part that is ruined by excessive heat. If the sheet is clamped too rigidly or
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Prevention is the best medicine. Follow these best practices to minimize the likelihood of hot crack errors: Hot cracking is caused by the complex interplay
, this defect is primarily managed by adjusting lead-in/lead-out settings, path rules, and cutting speeds to control heat input and residual stress. 1. Understanding the Causes