Hi there BillyBenJ! I’m Blake from Home Depot out in California. Although they may seem like similar tools rotary tools and drills are actually quite different.
Rotary tools like the Dremel, Roto-Zip etc. are high-speed low-torque tools that use finesse rather than power to get the job done. These tools are primarily used to cut, not to drill. Most will go all the way up to 10,000 RPM! Dremels only accept one shank size, so most drill bits will not fit into a Dremel, in addition drilling with a Dremel will be slow going as they have anti-seize protection built into the motor. (you will have to turn off then turn back on the tool)
Drills are more based on torque than speed. Even a contractor grade drill will rarely go any faster than 2,700 RPM. Although you could chuck a rotary tool bit into a drill I would not recommend it, because the drill goes so much slower than a rotary tool there will be an urge to use pressure to get the job done faster, this almost always ends up in a shattered bit which can be dangerous.
Quality rotary tools and drills are available at very affordable prices these days, and I would highly suggest picking up the right tool for the job.
Stay safe BillyBen and good luck with your projects!
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