I needed an apple grinder to make cider, but I didn’t want to spend the money for an expensive, store-bought machine. Instead, I found a new 1-horsepower garbage disposal on Craigslist for $70.
I mounted the garbage disposal in a wooden stand, using the same technique I would have used if installing it in a sink. Rather than use an actual sink, however, I used a stainless steel bowl with a hole in the bottom; this bowl acts as a funnel to help the apples roll into the grinder. I wired an on/off switch in the power cord to control the grinder. I sealed the switch with silicone for safe wash-downs, and covered the stand with several heavy coats of paint to create a clean, easily washable surface. This setup has worked great for my annual cider making.
If I were to build a more “professional” unit, I would consider using stainless steel fasteners, a waterproof switch, and plastic (instead of wood) for the stand.
I made a YouTube video about this homemade apple grinder, during which I explain the dimensions and basic building process. You can watch the full video on YouTube