welding line segments

arronpatton said:

I am left with 8 individual segments. 4 lines and 4, 1/4 circles that form the box. If I extrude these 8 segments I end up with an extruded border and not an extruded plate because the segments are not joined into one. Is there a reason why I cant join these together?

I don't have CorelCAD myself, but you could try using the "join" command, this should join all the items together into a single object (polyline) and then you should be able to extrude the object..

Perhaps the CorelCAD "weld" function is basically the same as the "join" command, in that case it should work but only if all items are coplanar and touching.

Did you try using fillet with a radius of zero to connect the lines and circles/arcs to make sure there are no gaps left before using the weld function. Even a tiny gap of one millionth of a millimeter might cause the command to fail. If the trim command is not a perfect trim there might be a very tiny gap left, hence the fillet suggestion.

arronpatton said:

lets say i have 4 circles setup in a square pattern and I want to connect them using 4 single line segments and then i trim the circles to give me a box with rounded corners. I am left with 8 individual segments. 4 lines and 4, 1/4 circles that form the box. If I extrude these 8 segments I end up with an extruded border and not an extruded plate because the segments are not joined into one. Is there a reason why I cant join these together?

In the CorelCAD Help you will find notes about the WELD command. There's certain limitations with regards to joining objects of different types. You probably need to have a polyline (instead of a simple line) to start with as base object and then weld the adjacent arc(s) and line segments to it.

Here's what the Application Help says:

Use the Weld command to merge two entities into one. You can merge Lines, open PolyLines, Arcs, elliptical Arcs, or open Splines. You can also transform Arcs to Circles and elliptical Arcs to Ellipses.

Use these guidelines when welding entities:

• Lines must be aligned in one direction. You can join Lines that are co-linear, in which case the farthest end points remain and a new line connects them. 
• Arcs must share the same center point and radius. Arcs are joined counterclockwise beginning from the source entity. 
• Elliptical Arcs must lie on the same Ellipse. Elliptical Arcs are joined counterclockwise beginning from the source entity. 
• PolyLines can join Lines, Arcs, or PolyLines resulting in a single PolyLine. You can only merge entities that lie end-to-end to the source PolyLine and attached specified entities. The entities must lie on the same plane. Unlike joining Lines, Arcs, or elliptical Arcs, you cannot join entities with a space between them if the source entity is a PolyLine. Note that the EditPolyLine command also lets you join entities to existing PolyLines.  

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Best regards,
Klaus.