Using a Dremel tool to trim pet rat nails: The goal of using a Dremel tool is to round off a finger or toe nail tip, rather than snipping off a length of nail. Using fingernail clippers can often accidentally result in cutting below the quick, which may start bleeding that is difficult to stop. A Dremel tool doesn't lend itself to that dangerous mistake as long as it's used cautiously and correctly.
In this video, Dr. Anthony Pilny makes using a Dremel Tool to trim pet rats' nails look easy. In fact it is easy as long as several important requirements are met: (1) The human needs to be trained in advance to use a Dremel tool, (2) A helper human is required to hold the rat, (3) Use a small, slow-speed Dremel tool, (4) Train the rat in advance to accept the noise of the tool, (4) Train the rat in small steps, such as doing one nail at a time over several days, (5) Be sure to hold the toe being trimmed firmly, bracing it against the spin of the Dremel.
CAUTION IS THE NAME OF THE GAME. Dremel tools, if used improperly, can be dangerous. They can burn skin, or shave off part of a toe. If you have all the precautions in place, and are well trained, and have a helper human, using a Dremel tool can be a great alternative to human fingernail files or clippers.