You will get more variation from other factors. Your Router / Lift
combination doesn't have to be super accurate. A slight warp in the board, a
little sawdust under it or between the fence, some flex on the tabletop or
fence, sanding, effects of humidity, etc. will negate the accuracy to
1/1000" from any tool. And, what about the rest of your project? Anything
you cut with other tools will be less accurate, and as soon as you start
sanding.....

So, reasonable accuracy and a well built, easy to use accessory is the key.
I use a PC690 under my table without a lift. Eye-balling, a ruler with
1/64ths graduations and most importantly, set-up pieces and test pieces,
does the trick for me. Would I like a lift? Yes, and will probably buy one
some time. But the height adjustment accuracy won't be the top priority.

Michel.


The routers with built in lifts are a lot less accurate (I think -- on
the order of 1/128'th of an inch versus 1/1000'th).