Hi
Most of the routers have a chart ( sticker ) on the motor,,,that SUGGEST the speed but a good rule of thumb always use the number #1 setting to start with the router as a voice and it will tell you to bump the speed up or down...heat will cook the bit by running it high speed when you don't need to...
Speed kills most things, like router bits...speed = heat...
Router Speeds!
http://www.routerworkshop.com/routerbits.html
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