We’re always learning new things every day. Today we learned that the Wonder Junior had a different style auger for the first batch or two that came off of the assembly line (early to mid-2008). This original auger had more of a square head to it. As such, the plates (both stone and stainless steel) were also designed that way. After these first few mills, the auger was redesigned to include more rounding. The plates were also redesigned to match the new auger.
In 2011, the auger went through another redesign, but the head on it did not change. It is interchangeable with the previous model, so most customers are able to swap out augers if you would like to try the new one. However, if you have one of the few original sets out there, you would also need to upgrade to a new set of plates (stone, steel, or both). You only need the new front plate, so as long as we have some in stock, we can offer them at a reduced price from a complete set (front and back plate).
You can see a picture of the original style heads below as well as a picture of the new design of the part that connects into the front plate. Note the flat versus rounded sides. Alternately, you can grind the new auger to fit inside the old heads, but you may prefer to just upgrade to a new set of burrs.