The Cam feature will produce various inputs that a board house might use and its not much good without further processing to obtain Gcode from.
You need the gcode ULP ftp://ftp.cadsoft.de/eagle/userfiles/ulp/gcode.zip and use the four ulps included to produce outline, drill and top and bottom isolation paths.
Note the gcode for the paths to isolate the traces has no offset. If cutter width is wider than the trace you'll remove the trace. To compensate you need as small a cut as will pierce the cladding and play with your trace width so that you have the desired width of trace plus half the cut width either side of the trace. Also note the gcode produced will cut all the outlines. If two traces share an isolation the gcode will still cut the edge of both traces..
It's sometimes fiddly but it works. personally i use the outline and drill gcodes and drill the board first. Then use TTransfer or photo and etch doublesided using the holes to align.