I bought a Router Razier to install onto my TR12 (non variable speed
hitachi). It took me a bit longer then instructions, however it was
easy. I use this on my router all the time in the table. My "insert"
is two pieces of 1/4" hardboard glued together and drilled out. If it
flexes I don't see it. Cost was basically $2.00 worth of scraps.

You can still plunge the router with the router razer, so if you want
to take it out of the table it is an option.

Alan