Hi all a bit of a set back today but all part of the learning curve.
I was not sure how to fix the legs and frame to the Coffee Table top so sent a couple of pics to my Brother Chris to ask his advise as he is a Joiner and Machinist .He told me the best way to do it which I will show you on the new rails.
He pointed out some errors I had made and how I had made life difficult for myself.
The picture below shows a dry fit and nothing is glued .If you look carefully at the picture you will see that the rails go strait into the Mortise and this is wrong there should be a proper Tenon on the end of the rails and the shoulder on the rail should be against the leg with the Tenon going into the Mortise.There should also be a small gap between the end of the Tenon and the bottom of the Mortice.It was also pointed out that taking the Taper the full length of the Leg makes it more complicated when making the mortise on the end of rail because the shoulders would have to be cut at a corresponding angle so the best way is to stop the taper below the rail creating a parallel surface to fit the rail to.
This picture shows the dry fit and is the one I sent to Chris from this picture he was able to point out my errors and give me some sound advise
So rather than carry on knowing I was wrong I have reduced the Taper on the legs and they now end below the rail I will have to make new rails because these will not be thick enough to create a proper Tenon using the existing Mortise.