Hank has been out in the pasture pushing a week now. We have some rocks, and a gravel driveway. He had his shoes pulled 3 weeks ago, and has started to get enough hoof growth, to then chip and chunk some in his running around in the pasture. I am really horrible with a rasp, usually taking off more of the skin on my knuckles and fingers, than the hoof. I also found my back can not handle the time I take to clean things up with a rasp, so I started using an electric grinder a few years ago to do small touch ups between farrier visits to keep the little chips from becoming BIG chips out of the hoof on the horses who are barefoot. Because Hank has been shod most of the time for rides, he has had minimal grinder experience. But, I decided to give it a go, and see if he remembered it from a few years ago. I drug it out, and he was standing there, before I slipped a halter on to tie him, and I hit the on button, and he just looked as it made noise. So, I picked up a foot, and gave it a little "zip" and again, he just stood there. After I got the first hoof done, I decided that we needed a video of the horse who has been scared of his own lead rope in the past, standing there with nothing on him as I took a grinder, with the cord going in front of him, and touched up his feet. He has spooked at the garden hose in front of him getting a bath! We did some work last week with a cotton rope around his front legs. Learning to give to the pressure when a rope is hooked behind the leg, and you ask the horse to move a leg towards you when you pull both ends. The lessons went well, and maybe he is understanding these things (ropes, hoses, and cords) are not going to "get" him. One thing about his being set back in his being worked much since surgery is I can do some ground stuff I have been meaning to do. Seems to have already paid off a bit!
(and note, the grinder can take off a LOT of hoof fast if you are not careful. If you decide to try this on your own horse, be VERY careful. Were protection like you would using any tools. Eye protection to keep hoof dust out. Hair out of the way etc. And be familiar with the tool, and completely comfortable. If you have doubts, then don't try it.)