TC Mitring Tutorial first created 21/01/06 - last modified xx/xx/xx Page Author: Ty Harness

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Draw the cross section profile of your moulding. If you only need to produce a 3D visual appearance of moulding then you do not need to draw the exact combinations of arcs and lines. Of course if it's a real job and you're making the tooling for a spindle moulder then you should start with a very accurate 2D profile.

Figure 1 - Cross section of moulding - A close pline

Ensure that the 2D profile is a continuous closed pline. Use the Join Polyline method in TC if you need to. I like to check it is continuous by either hatching or examining the area property on the properties palette. If it is not closed the 3D extrude will only be made up of faces and the Boolean operations will not work.

Prepare (what I call) some construction lines not to be confused with TC's construction lines. i.e. the plan of the cabinet or bay window etc.

Figure 2 - Octagon construction lines note the radial slice lines forming the bisected angle.

The radial slice lines (angle bisections) will be needed when I invoke the 3D slice command later. The slice line is the bisected angle - I've only chose an octagon for the sake of this tutorial.

View the drawing in Isometric

Then extrude the profile into 3D. Right Button (RB) and select the profile and choose properties from the menu and enter in height for extrusion. (Note you can do it with the normal extrude method if you prefer).

Ensure that you are in 3D editing mode or you won't be able to control the SEKE points correctly.

Figure 3 - Going into 3D mode - Extrude the moulding profile to a greater length than required.

Rotate the moulding into the correct orientation just Left Button (LB) select and tab into the rotation boxes and rotate about the appropriate axis. Never do any of this free hand with the mouse.

Move the control point by LB select and press SEKE D (I've moved it to middle point of the moulding) and snap the moulding to the 2D constructions lines.

Figure 4 - Use SEKE to position moulding on mid point of the octagon side

View the drawing by plan.

Select the 3D slice tool

LB Select the moulding first and then each end of the slice line we created earlier. Remember to use SEKE V to select to either end of the moulding. Never do this free hand. The secret here for a correct slice is the orientation of the view port. Trying to slice a compound mitre would be too tricky.

Figure 5 - Slice through the moulding - note use SEKE V to snap to ends of slicing lines

I can repeat the 3D slice procedure on the other end of the moulding and then view in isometric mode again. Then finally select and delete the unwanted ends of the moulding.

Figure 6 - Sample picture description here

I can then rotate copy every 45 degrees to add more moulding without going through any more 3D slicing but that's only because the octagon side length is regular.

Figure 7 - Finished Mitring

You can then insert your moulding into (say) your bay window drawing or make detailed fabrication drawings as required.

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