As others have said you can make this in several ways. You can use a TS
alone to make it, a router alone will also work but I think combining the
two methods will work better and at no additional cost in having to purchase
a 90deg router bit (to cut the 45deg angles).
Set the TS up to make the 45deg cuts then use the router in a router table
with a bit to hog out the inside groove. If you don't have a router table
you can easily make a temporary setup. Rather than giving instructions here,
I'll just point you to Pat Warner's site www.patwarner.com and you can poke
around there to get the info you need.
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