Help needed with AutoCAD R14

[cropwell]

Ey up chaps, I'm stuck.

I have got a very old version of AutoCAD loaded on my CNC computer, which has no unnecessary software (networking etc), so the easy way of explaining my problem is to start with a photo of the screen


What I am making is a harmonica case. The inside cutout is two rectangles and two circles. I want to end up with a pocket which is the combine of the four shapes. I can do the drawing in Coreldraw, and weld up the shapes, but when I transfer it to the CAM program (EstlCam) it produces a very 'steppy' outline, which is no use. I have to export the drawing to a .dwg file with Corel and then open it in AutoCAD and export it as a .dxf file to go into Estlcam. Somewhere in this process it loses the continuity of the shape.

How do I make the four shapes into one outline ?

I must admit that I do not understand the AutoCAD terminology. The program was bought for my son when he was a student in the late 1990's and I am unwilling to spend money on a CAD program, when there are so many free ones about and I am unlikely to use them to any worthwhile extent.

Cheers,

Rob