Thanks Anis, yes the method is OK, but I spent all the time trying to get the method right, then no time left to get the object perfect!! But I haven't seen your final entry?

I learned a lot from this shape so I will show the method in case it is useful to someone:

Draw the first profile and revolve


Top view, show points, scale two selected points from centre


Front view, move two selected points down

This surface will not shell (see http://moi3d.com/forum/index.php?webtag=MOI&msg=2117.4)

So workaround discovered by DannyT, cut it in half then shell, then fillet edges


Also thanks to Danny, delete the two selected surfaces


Then mirror/copy and boolean union.


Voila:)