My router kit came with a centering cone for centering baseplates on the router. It works fine, but I always found it a hassle to chuck in the bit blank and use the cone each time I needed to change baseplates. I frequently change baseplates to switch between bushing guides, large bit profiling, circle guide jigs etc.
To solve this problem, I switched the panhead screws out for some tapered machine screws. Now when you screw the baseplate on, it centers itself. One less step each time I switch bases!
I confirmed that the baseplate was centered with the centering cone. On all three bases – plunge, fixed, and D-handle – the tapered screws centered the baseplate.
With the new screws installed, the baseplate self-centers without using the centering cone. The accuracy is perfect, which is important for inlay work or dovetails.
The holes in the baseplate are stepped, and taper inward.
The screws are 8-32×3/8” long tapered head machine screws common at most hardware stores. These fit my Dewalt 618 router.
If your baseplates are different, installing washers on the screws may work. The I.D. of the washer would need to match the screw shaft, and the O.D. would need to match the hole in your baseplate.
-- Willie, Washington "If You Choose Not To Decide, You Still Have Made a Choice" - Rush