I started out dremeling my Rottweilers' nails with a cordless one. I found the same thing as Ms Stella so I bought a full-size corded one. When I got my mpoo, Cali, I knew I wanted to dremel her nails and didn't see any reason to downsize the dremel. I have always had a flex-shaft attachment for mine though that makes it much easier to use since you don't have to physically hold the heavy dremel. https://www.dremel.com/en-ca/Attachm...spx?pid=225-01
Here's how I trained Cali to accept it. For the first week, I didn't turn it on. On the first day, I just put it down beside her on the table where I groom her. She sniffed at it and I gave her a treat. Being a poodle, by day two she couldn't sniff it enough! LOL On day 3, with it still off, I briefly touched a nail with it and treated. She didn't look the least bit worried, so I touched another nail and another treat. I was able to touch all of her nails on day 3. If she had shown any hesitation, I would have stopped for the day. The next day, she actually lifted her paw up when she saw the dremel approaching her! LOL I didn't want to rush her so I just spent the rest of that first week slowly increasing the length of each touch and treating for every single one.
Week two, I turned it on but didn't take it anywhere near her. Being a poodle and having had FFT done, she didn't seem unduly upset by the noise. I was stuffing her face full of treats the whole time. I did this for a few days and then very briefly touched one nail with it on. She looked a tad apprehensive so I stuffed her full of treats and didn't go any further. I just moved at her speed, taking my cues from her as to when to increase the number of nails and length of dremel time on each one. By the end of week 3 I was dremeling her nails.
I always give her a little treat for each nail I do. She's so blase about the whole thing now, and so focused on the treats, that I sometimes wonder if she even notices her nails being done.