45 degree lock mitre bit...help

Try this:

If that doesn't help, define "doesn't seem to come out right" with more detail.

A zero clearance insert in your router fence will help. Making sure that your stock is FLAT and the edge straight and square to the face - all are essential. Any warping, twisting, cupping or bowing and you won't get a nice uniform cut along the routed edge

A pair of quick and dirty jigs like these, which also serve as backers to minimize tear out at the end of the cut, are also handy.. (all one line so watch the line wrap)

Plus: How do you know that your fence is square to the table? When I got an engineers square from Lee Valley (accurate to .001) I found that all my squares were off by a bit. Had to adjust them. Previously had trouble with matching up glue edges etc. because I was setting things off by a bit.

Palmer,

When I purchased mine from Rockler, I also purchased a plastic setup jig that set the fence and the height correctly. After a few test cuts, it was working fine. I would recommend a zero clearance fence.

David