Bests & Worsts Reviews from Amazon

After five years of manual scooping, I decided to jump into the world of automated feline waste disposal. A buddy of mine has had the previous version of this litter box for about a year, and he loves it. This was enough for me to give it a shot. The only thing he mentioned as far as potential negatives is the possibility for the motor to burn out, as stated in comments and reviews by many other users. The solution to this is simple - use an outlet timer (much like what you might use for Christmas/holiday lights) so that the litter box is only in operation about 50% of the time. This newer version has a timer built in - I believe it runs for 90 minutes, then takes a break for an equal amount of time. In addition, it features a slot for a carbon filter over the waste bin to help reduce odors. Mine basically worked right away. I initially had a problem with the "box" not properly spinning (I could hear the drive gear "popping" as it tried to rotate the box), but this was my fault due to piling in too much litter to begin with. Once I removed some and got it down around the indicated line, the litter box was running just fine. It's super silent when running (the only sound I notice is when the litter sifts and falls through the back side of the deflector arm leading into the ramp), and my cats, at least, took to it with no issues. *** UPDATE *** Well, after about a week, I started experiencing the blinking red light, similar to other reviewers. This indicates a problem with the bowl motor. A little bit of observation showed that, indeed, after a few minutes following connection of the power cord, the bowl would hang up, and I would hear the "popping" sound that I mentioned in my initial review. If I gave the bowl a manual assist, it would actually resume turning for a few more minutes before eventually ending up in the same state. After a few minutes of not being able to rotate, the control board evidently turns the bowl motor off completely until a power cycle is performed. As an electrical engineer by profession, I have a habit of taking my apparently slightly non-operative devices, tearing into them to see how they function, and more often than I care to admit, rendering them permanently non-operative. However, I do have a success rate to speak of, so I decided to start digging. Before proceeding, I must preface by stating that all of the below is, without a doubt, 100% warranty-voiding. Use appropriate discretion if you choose to reproduce any of my efforts. To begin with, it was apparent that the drive gear beneath the bowl was simply having problems turning the bowl itself. There are small plastic wheels located in the bottom of the bowl housing to help keep the bowl spinning freely, but the bowl also makes contact with the center peg/axle of the housing. I first applied a solution that has proven fruitful in many other instances in my life: lube. I used some general purpose automotive grease on all of the small wheels, and around the bottom of the center peg. This definitely improved the situation, but after a long enough wait, I'd still end up with the blinking red light. Next up, I disassembled the drive gear housing. Aside from the large gear that's visible at the bottom of the bowl housing, there's a smaller intermediate gear with a tab that actuates a small switch as it spins (this is how the controller "knows" if the bowl isn't spinning) and the drive motor. On closer inspection, I could see where the tips of the teeth on the intermediate gear had been worn down a small amount. The "popping" sound I'd been hearing when the bowl quit rotating was, in fact, the tiny gear on the drive motor shaft slipping past the teeth of the intermediate gear. The compounding problem is that the overall issue of the bowl not spinning is simply exacerbated by this behavior, as it makes it progressively harder for the motor gear to deliver power to the intermediate gear if it's also wearing down the intermediate gear's teeth in the process. The fact that these two gears were slipping past each other led me to believe that their teeth weren't really engaging as well as they could have been. Sure enough, removing the screws securing the drive motor, I could push it a small amount further into the intermediate gear. To boot, the shape of the teeth on the drive motor gear don't match up perfectly with the teeth on the intermediate gear (though, mechanics not being my area of expertise, this might be intentional). I thusly modified the drive gear housing such that I could mount the drive motor slightly closer to the intermediate gear in order to get better tooth engagement. This involved sanding/snipping some of the locating tabs, filling one of the factory screw holes (epoxy would have been perfect; I used J-B Weld because I had some handy), drilling a new screw hole (I started with a 1/16" bit and stepped up to a 3/32" bit), then re-mounting the drive motor. After re-assembling everything, and adding a little more lube to the wheels and center tab of the bowl housing, my modifications seemed to prove effective. It's only been a few hours since I put everything back together, but I've had a solid green light and a constantly rotating bowl during that time (excepting, of course, the periods when the built-in timer shuts things down). I've understandably knocked a couple of stars off my initial rating. The concept of this automatic litter box is great, and the waste conveyor system works perfectly out of the box. However, there's clearly room for further improvement. *** UPDATE *** Unfortunately, I've got to knock off another star, and admit that I'm giving up on this particular automatic litter box. The short version is that I've been through two of these boxes now, and am continually encountering failures of some kind. The latest is that the bowl motor has developed a screeching/rubbing sound that's loud enough to keep me up at night. The overall concept is solid, but cheap components and poor design decisions have me now looking to other manufacturers.