On Wed, 11 Apr 2012 22:11:38 -0400, Bill wrote:

I find that fairly compelling. I'd pay $200-250 for a cast iron top.
But TS-add ons I see seem to start closer to $300-400 and have
non-trivial install. And I suspect one still has to buy an appropriate
router insert.

The router insert is open to discussion. On my cast iron contractor's
table saw wing, I used a cut off wheel in a grinder to cut away the
enough of the ribs underneath. Then used a hack saw to cut a round
circle for my Makita 3612br router, which I bolted directly to the
wing. This was some 35 years ago. Took me about three hours to do the
entire job.

If it had been an insert, I suspect the process would have been much
easier. Hacksaw to cut a square plate out and bolted on retention
supports to stop the insert from falling through.

To be honest though, considering the weight of the cast iron wing and
the added weight of the router, I'd go with a melamine wing these
days. Easier, faster, cheaper. Can't beat those three reasons.