I’m looking for a tool path that lets me index these legs to the table top. I can clamp the legs 90 deg to the cnc table and do some cutting, but I was wondering if there was a way to do it with leg flat on table.
This isn’t directly responsive to your question, but another approach to the vertical method (assuming the legs are not too long) is to install vertical workholding on your machine using the Avid kit for that purpose. Vertical workholding would also enable dovetail/finger/box joinery using the relatively inexpensive JointCAM software. If this appeals to you, take a look at the excellent YouTube video produced by Jim Neeb (JN Woodworks), based on his own Avid setup.
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@Bstanga I’m not quite sure I understand the question, … is it that you want to find a way to index the leg to the bottom of the table when it is inset away from the corner and placed at an angle of some sort? For that it might seem that a very shallow pocket (0.0625in or so) would do the trick. Maybe this is not what you are asking though as I’ve seen enough of your posts to know you have likely thought of that.
I am looking for a way to cut a dovetail joint or similar in the table top and leg without cutting the leg part in the vertical. I have a wide variety of bits and cutters, I feel like there is a way to do it I just can see it in my minds eye…lol
and the leg s will be on the very corner
could you use a “round” - dovetail?
In the table top eat out most of the material with a regular end mill and then go in with a rotary burr (many passes 0.030in step over at extremely high feed rate) to cut out the ear lobes.
I use 1in diameter rotary burr’s like the following for this sort of thing. In material like wood, as long as you keep air blowing on the cut to get the saw dust out they can remove a whole lot of material really fast… I use burr’s because I have them for other reasons, … I really should go out and buy some router bits for this which would be a more appropriate tool, I could lower the feed rate and increase the step-over and be less worried about catching things on fire if the air supply stops. 
There are bunches of shapes of rotur bits that could be substituted. A 1" bit on a 1/4in routher shank gives 3/8in under-cut so from that one can easily figure the maximum size cut based ont eh width of the “neck” one wants to leave.
With this setup, one can cut the table flat, and the let flat, flipping the leg only once in the middle of processing.
Splines could work.
They could be flush with the leg or coved or at some angle as shown here. It would help to make them as deep across the leg as possible with the splines aligned with the grain direction of the top. You can chisel the corners or round over the splines. Maybe more than two would fit.
A bridle joint could also work. You could chisel the corners or try to make everything fit right off the machine (leave gaps or figure out the right combination of round-over bits, etc.). The tenon goes in the direction of the grain of the top.
It wouldn’t have to be full-depth in either direction. A completely housed version would allow you to leave strategic gaps to account for rounded corners.
Thanks DA, out of all the tools I have I do not have a round burr, but I will have some soon.
