Plunge router question

[Jim Allen]

My question has to do with the flat edge on one side of the router, what's it for? I've done a bit of routing using fixtures to maintain the correct distance and have more than once, going around a corner ending up with the flat edge on the fixture, altering the design by the distance of the flat area. I'm planning on rotating the sub base to prevent it from happening again, but it seems rather difficult to get it placed just right.

[Jim Becker]

The flat on the base can be useful for a number of things, including running it along a rail with more stability, allowing for getting closer to an obstruction, allowing an edge guide to get closer to the center of the cutter, etc. There's nothing that will preclude you in most cases from installing a fully round sub-base on the machine, however, if that better suits your needs for a given operation.

[Ken Fitzgerald]

One of my PC routers has a flat edge on it. I find the flat edge handy when I am routing dados. The flat edge follows a straight edge quite well. I use the curved portion. When I am using jigs or fixtures, I do on my router table which uses a different PC router.

[Jim Allen]

Thanks for the info, I do most of my routing on the router table, so I've never thought about the flat for any of your suggestion. Something to keep in mind.

[johnny means]

The flat is also a more consistent reference for riding along a guiade or fence. A round base can vary in width around it's center, if not perfectly centered.