The PROJECTA-SET method for adjusting TIMKEN tapered roller bearing clearance is similar in concept and application to the ACRO-SET method, but adds additional variety and complexity through the use of special measuring fixtures. This gage projects unmeasurable shims, spacer gaps, or reference surfaces into an easy-to-measure location. This type of gage is usually used for dial indicators or LVDTs that take readings. It is also ideal for designs that employ a tight fit on the adjustment component (inner or outer ring) without sacrificing assembly speed or accuracy. The method (Figure 12) involves two important gauges: a spacer sleeve (reference C) and a tapered measuring sleeve (reference D), usually equal to a known design length (reference X). These sleeves will project an inaccessible spacer gap to the shaft end. To illustrate the PROJECTA-SET method, refer to a typical main shaft assembly (Figure 13). In this back-to-back mounted inner ring adjustment design, bearing clearance is obtained by using a spacer between the small end faces of the two inner rings. In this application the outer and inner rings are slightly tight fit. The required measurement steps are: 1. Place the assembled drive gear shaft (except the upper inner ring and spacer) on the lower platen. Place the gage on the upper bearing outer ring and then into the upper inner ring (Figure 13). 2. Apply pressure to clamp the gauge between the two bearing inner races. In this case, the known axial load can be transferred to the measuring tool by means of the inner disc spring. (Note: The purpose of applying pressure is only to clamp the upper inner ring in place against the spacer sleeve to properly seat the bearing. Some gauges do this with a nut). 3. Swing the measuring instrument (handle) to seat the bearing rollers in place. The LVDT probe measures the axial displacement between the two gauges and the desired spacer size reading is displayed on the digital display. 4. Use a gage to determine the spacer size according to the following equation (Figure 13): S u003d Z - A + K where: S u003d size of spacer required, Z u003d sleeve length (fixed value) A u003d inner and outer rings Variable distance between two corresponding diameters on the cone of the locator. (dimensions for zeroing known) K u003d constant, compensating for system deviation due to gage spring load, average inner ring fit effects (clearance loss) and required bearing clearance G u003d clearance measurement, representing the change in distance A. Distance A includes special considerations for the GPROJECTA-SET method: 1. The size, weight, cost and design of the PROJECTA-SET gage should be checked for the specific application. Typical measurement costs for industry applications, including LVDTs and gage internal springs, are approximately $10,000 each. To improve the efficiency of setting clearance, for assembly volumes exceeding 30,000 per year, designers should consider using special automatic compression designs and the use of compression fixtures in the measurement. 2. If different bearing series and different types of shafts are used in the same application, then separate measuring instruments or interchangeable parts (ie double cones) are required. 3. Just an alternative to setting the clearance for tapered roller bearings (ACRO-SET is similar to PROJECTA-SET and should be considered first). Advantages of the PROJECTA-SET method Eliminates time-consuming disassembly when replacing gaskets or spacers in applications where the inner or outer ring fits tightly Can be easily applied to automated assembly processes Minimizes manual judgment compared to traditional manual methods in the past Minimum training time required to use PROJECTA-SET gages The PROJECTA-SET method provides consistent, reliable set play.