A machined casting can meet its hole dimensions while retaining a burr where two passages intersect. That burr may be difficult to see and harder to remove after assembly. Deburring therefore belongs in process planning, especially for features that communicate with fluid passages or moving components.

The requirement should define the acceptable edge and cleanliness condition. A broad instruction to remove all burrs is less useful when the geometry leaves no practical access or when excessive removal could damage a sealing or flow feature.

Identify intersections on the drawing

Section views can reveal cross-holes and internal breakthroughs that are not obvious in exterior views. Mark the regions where a burr could affect function. The machinist needs to know whether an intersection is simply a clearance feature or part of a controlled passage.

The sequence of drilling and other operations can influence the remaining edge. Review the complete route rather than treat deburring as a final manual step that will somehow reach every surface.

Compare access routes before choosing a process

The table identifies decisions, not universal process recommendations. A specialized deburring method must be compatible with the alloy, geometry and final requirements.

Define the edge condition without over-removal

A burr-free requirement does not authorize a large uncontrolled chamfer. If the edge influences flow, sealing or strength, specify the permitted condition. The finishing method should preserve the intended geometry and any minimum wall requirement.

An illustrative problem is an internal intersection near a thin wall. Aggressive cleanup may remove the visible burr but enlarge the opening beyond the intended boundary. The acceptance plan must evaluate both the absence of loose material and the remaining geometry.

Separate removal from cleanliness

Removing a burr can create chips or abrasive residue. The cleaning route must address that material and verify the required final condition. An apparently smooth edge does not prove that the passage is free of debris.

If a borescope is used, confirm that it can view the relevant intersection. A partial view should be reported as such. Additional verification may be needed for features that cannot be seen directly under the agreed method.

Validate the route on representative samples

Use samples with the actual intersecting geometry and processing sequence. Record the before-and-after condition and any dimensional effect. A successful trial on an open hole does not necessarily qualify a deep cross-hole with different access.

For TripleAce Castings enquiries, provide section views and highlight critical internal intersections. The foundry and machining team can then review access before tooling and process decisions are fixed. This avoids a late-stage choice between accepting an unresolved burr and redesigning an otherwise completed component.

Inspection background

ASNT: Visual Testing Overview discusses structured visual examination and aids. The deburring route and acceptance condition must be qualified for the specific casting; this article does not prescribe a universal edge break.