I have 4 different drill bit sizes with all different shanks and two end mills to cut out counters. Most drill bits are rated at 2800-8000 rpms, router only go down to 8000 and I don’t want to buy collets for every drill size.
What do you do when you want to drill?
Is a router only good for routing?
If a drill or endmill is rated at an rpm what will happen if you use it at a higher rpm?
What do you do if you have a CNC that uses a porter router to drill/Mill?

Is a router only good for routing?
You can spin wool rather fast if you want to. :)

http://www.5crossb.com/images/phoebe/wheels/spin_alpaca.jpg

Is a router only good for routing?
If a drill or endmill is rated at an rpm what will happen if you use it at a higher rpm? What do you do if you have a CNC that uses a porter router to drill/Mill?

You can get small router bits or endmills with a 1/4" shank. The smallest you can find is the smallest hole you can make. But you can make any size hole with a smaller bit. If you use an 1/8" bit, you can make any size hole 1/8" and up. A larger hole is just a circle with a smaller tool.