Similarly, you can't cut a 3mm internal radius with a 5mm cutter. If you want to do this, import/draw the cutter centreline not the slot. Don't ask the CAM to cut a slot 5mm wide with a 5mm cutter. The direction in which you join your individual polylines affects the direction in which they are milled. This is especially so for stuff that is mirrored and copied. The order in which you draw stuff affects the order in which contours are machined. The parts need to be on one layer, and a closed (if applicable) 2D polyline of zero thickness. Hence, I can only speak from my experience with Acad to DXF to Partmaster. To start something I may regret, are you sure you know what you doing when you export your DXFs? I am on shaky ground here as I've never used CamBam, but the reviews are good and the forum is helpful. The US site is way more developed than the UK one where the product originates, and suggests they have a 'hobby' pricing structure. Their licensing system stinks but the product is quite good. To answer your specific question, you could have a look at Dolphin Partmaster.

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