The Powermatic 1285 jointer is the standard model of the 12-inch jointer range by Powermatic. It is nearly identical to the 1285 with helical cutter heads, which (as expected) has helical head cutters instead of the standard straight blades found on the normal 1285.
The 1285 jointers have a parallelogram base, which makes changing the height easy and not as prone to wear as wedge-bed jointers. The basic design of the 1285 is very similar to that of Powermatic’s 8-inch parallelogram jointers (the PJ882 series).
The main difference between the smaller PJ882 and 1285 jointers, besides the size, is the design of the fence. The 1285 has a rack and pinion design that makes the fence very stable and sturdy. However, it lacks the handwheel to set accurate angles, making it a lot more finicky to set a precise angle than on the PJ882 models.
The main downside of the Powermatic 1285 is the use of straight blades rather than helical head cutters. Straight blades are much more time-consuming to set up, last less long (helical head cutters have 4 useable sides), and make more noise.