CorelDRAW X5 :: Combine Shape Into Single Object Created By 3 Hexagons - Reducing Lines

I have a shape created by three hexagons and they are abutted along edges. I would like to combine them into a single object and in doing so reduce the lines so that the abutted lines become one line. the reason is that currently they are processed twice along each abutted line by my laser.

I can use combine but this still leaves them as discrete editable shapes in node editor, so clearly the double lines are still there.

If I use weld I lose the lines.