Designing Normalized Coped Cuts on Round Tube

This method is a reliable way to normalize cuts on round tubing and only requires three tools. It involves replacing faces with a ruled surface.

Start by clicking the Ruled Surface tool from the Surfaces tab. Before selecting anything, set the “Type” to “Normal to Surface”. This will make the ruled surface extrude normal to the surface of the tube. 

Next, select the inside edge of your cut feature. This selection will be recorded as the “Edge Selection“. A yellow preview of your ruled surface should appear.

Then, input a distance greater than the thickness of your tube. The ruled surface should extrude past the outside surface of the tube. You may need to click the “Reverse Direction” icon to change the direction of your ruled surface.

Finally, click OK.

Pro Tip: If the ruled surface is not extruding outward, select your edge from the Edge Selection and click “Alternate Face”. This will alternate the face the tool is referencing. 

Now that you have your ruled surface, click the Replace Face tool in the Surfaces tab. 

Start by selecting the “Target Faces for Replacement”. If there are multiple target faces, make sure to remember the order you select them in.

Next, select your ruled surface as the “Replacement Surface”. If your ruled surface has multiple faces, be sure to select them in the same order you selected the target faces. Every target face should have a corresponding replacement face located such that the replacement does not create self-intersecting geometry. Otherwise, your feature will receive an error.

The ruled surface may be automatically selected. If the feature results in an error, right click the “Replacement Surfaces” and click “Clear Selections”. Then manually select the “Replacement Surfaces”. 

Finally, click OK.
Pro Tip: In rare situations, the number of “Target Faces for Replacement” will not equal the number of “Replacement Surfaces”. To fix this, use the Knit Surface tool from the Surfaces tab to knit faces of your ruled surfaces together until every target face has a corresponding replacement surface.

To remove your ruled surface, click on the Surface Bodies dropdown in the FeatureManager and select the surfaces making up the ruled surface. 

Next, right click and select the Delete/Keep Body tool. Change the “Type” from “Keep Bodies” to “Delete Bodies” and click OK. Your ruled surface should now be deleted.

This method is the quickest way to normalize cuts on round tubing, requiring only two tools. This method can normalize multiple cuts on a round tube at once; however, any mitered cuts will be incorrectly normalized using this method. Be sure to normalize miters separately. Review Designing Normalized Mitered Cuts on Round Tube to learn how to do this.

Start by clicking the Delete Face tool in the Surfaces tab. Next, select all faces on your tube EXCEPT the inside face. You can do this by selecting each face individually, or by selecting the outside face and clicking “All Outer and Inner Loops” from the selection toolbar. Check the Options dropdown and click Delete. 

Click OK. You should be left with the outside surface of the tube and your ruled surface.

Now that we have isolated our inside surface, select the Thicken tool in the Surfaces tab. Select the inside tube surface as the Surface to Thicken. Change the thickness direction until the feature is thickening outward. The yellow preview should be outside of your tube.

Enter the wall thickness of your tube and click OK.