I bought an old router at an auction a while back and the bearings are shot. The oiled bronze top bearing is easy enough to figure out but the ball bearing in the bottom (where the bit mounts) is marked 7R8, which is a .5 inch by 1.125 inch bearing, about .310 thick. Looking in my MSC and Enco catalogs, I find bearings that size but they are only rated up to about 5K RPM and the router goes 23,000 rpm.

I might go to the local bearing house tomorrow but thought that a web supplier like Enco might be cheaper. Does the 7 mean high speed? Will a standard bearing work or will it burn up quickly?

The router isn't worth a whole lot even if I get it fixed, although it would be handy to have one with a round over bit ready to go w/o having to change bits all the time.