Sheetcam Hot Crack _top_ Jun 2026

A hot crack is a fracture that forms as the metal solidifies from a molten state. In CNC plasma or laser cutting, the cutting torch melts through the metal, creating a localized pool of molten material. As the torch moves away, this molten edge cools rapidly. Why Do Hot Cracks Occur?

Stainless retains heat and expands rapidly. Use overcuts and optimize cutting paths to prevent heat accumulation. Moderate-High

A hot crack occurs during the solidification phase of the welding or thermal cutting process. As the plasma arc or laser melts the metal, a localized pool of molten material forms. If this pool cools too rapidly, or if the surrounding metal expands and exerts tensile stress on the cooling zone, the material tears apart as it solidifies.

The where the cracks are forming (e.g., at the pierce point, on corners, or along straight lines). Share public link sheetcam hot crack

First, let's clear up the terminology. SheetCam itself is a powerful CAM (Computer Aided Manufacturing) tool used primarily for plasma, oxy-fuel, and laser cutting. The software does not physically crack metal. However, the toolpaths and cut rules you set within SheetCam directly influence the thermal input.

If you have optimized your SheetCam G-code and hot cracking still occurs, look to these physical variables on your shop floor: Impact on Hot Cracking

Even with perfect SheetCam settings, a can occur if your physical setup is wrong. A hot crack is a fracture that forms

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.

1.5mm – 3.0mm to move the crater away from the start point

A piercing delay that is too long (too much dwell time at the start) can cause "hot spots" at the start of cuts, increasing the risk of cracking at the hole or contour start. 3. Material Sensitivity Why Do Hot Cracks Occur

When setting up your operation, ensure your toolpath is configured to cut all internal contours (holes and slots) before tackling the external profile. While SheetCam's thermal distortion mode generally handles this well, you may need to manually adjust if you are working with extremely thin gauge metals or very detailed parts. Sometimes, breaking the operation into separate layers (one for holes, one for the outline) gives you ultimate control over this sequence.

The susceptibility to hot cracking depends heavily on the metallurgy of what you are cutting:

Users blame SheetCam because the software controls the path the heat takes. A generic or "lazy" setup in SheetCam creates a perfect storm for hot cracking:

Ensure your lead-in is long enough to keep the initial pierce puddle away from the final part edge. For thick materials, a lead-in of 6mm to 10mm (0.25" to 0.4") is recommended.