I came up with this idea to help my wife maintain our pet’s nails, we have a full family of dogs (3 total) and all of them had healthy nails that needed constant care. We went through lots of packs of batteries to keep the nail trimmer going at a good speed, and that was getting costly. Rechargeable batteries were not the answer because of the current pull being high and the voltage for rechargeable are less than regular alkaline.
I took the PediPaws apart to see what I was working with, and it was a simple on/off switch and motor using batteries, which is what I expected. The 2 batteries were in series, so I knew that the voltage was only 3V DC. I soldered some leads to the switch and put a barrel jack on the bottom, then used a standard Radio Shack variable power supply that ranged from the 3V - 12V to power it. Using that supply, I was still able to use the power supply for other projects if I needed to.
I bumped up the voltage from 3V to 5V to see if that would make the trimming time shorter, and that made the grinding head act erratic and removed to much nail while trimming. The battery output at 3V is the correct voltage to get everything working perfectly.
I give this project 0.5 stars because this project is something real simple, just some soldering. I just identified that having AC powered could be useful, as was, very. I don't know why there isn't a version of this product at offers this option; regardless, this worked out great and saves tons of money on batteries. I made an easy to follow step-by-step if anyone else wanted to do this with their PediPaws.