Abstract: A palletizer has an improved slide plate assembly and an improved indexing hoist. The slide plate assembly incorporates measures to reduce friction between it and the bags or other articles being handled by it. The orientation of the slide plates of the assembly are altered ninety degrees with respect to traditional slide plate orientation to eliminate the deadplate encountered by articles sliding along the slide plates. An air assist mechanism also is incorporated into the slide plate assembly to produce an air cushion between the articles and the top surface of the slide plates. The hoist, which is designed to index upwardly after receiving a layer of articles to compress that layer against the bottom surface of the slide plate assembly to flatten the articles and to force air out of them, incorporates an improved controller that causes the hoist to assuredly impart the desired compressive force to the articles without over-compressing the articles or overloading the hoist's lift motor.