Manufacturer: San-Val Trains, 7444 Valjean Avenue, Van Nuys, CA 91406. Price: $5.95 for two axles.

As with all but one aftermarket wheel maker, San-Val fits delrin plastic insulator bushings into the center of each wheel disc, and hydraulically presses the axles into the bushings. The double insulation allows the wheels to pick up electricity from the track for lighting a car, activating a sound system, or powering the motor from a locomotive tender.

The wheels measure 3/16 inch across the tread and 1 5/16 inches across the flange. They represent a wheel diameter of 33 inches in 1:32 scale--close to the most common (36 inch) size in standard gauge--and slightly over 26 scale inches in 1:24 scale--by far the most common size for narrow gauge. In 1:22.5 scale they would represent a wheel 24 inches in diameter, undersize for most applications except very early rolling stock or locomotive pilot trucks. But San-Val's 1 1/8-inch diameter wheel (actual inches) satisfies the need for LGB/USA Trains/Bachmann-compatible 26 scale inch replacement wheelsets.

The wheels' appearance is consistent with most of what is currently on the market: The wheel face is flatter than that of most plastic wheels, concentric machining rings and minor nicks are evident on the wheel face (they disappear when you paint the wheels), but the tread has a high polish. On one sample a tiny piece of plating had flaked off exposing the brass beneath; on another the wheel disc was not perfectly square on the axle so it appeared to wobble slightly when it spun. Neither defect seemed to have an effect on performance.

San-Val claims the design of its new wheels to be a synthesis of the best features of other aftermarket wheels. For example the flange is the same size as on an LGB wheel to allow it to roll over the plastic frog platform on an LGB turnout (to prevent wheel drop through the frog) and the transition from the tread to the flange includes a slight fillet to enhance rolling characteristics.

And the real test of any wheel is how it rolls. Our test included three other contenders: A widely distributed aftermarket metal wheel also of new design, a "premium" metal wheel, and standard LGB plastic wheels. We allowed four identical cars, one with each set of wheels, to roll unassisted down two different 2 1/2-percent grades outdoors on LGB track. The cars finished in exactly the same order in both tests. One wheelset was a clear winner, rolling about eight feet. The remaining wheels all finished about four feet downgrade, within four or five inches of one another. The San-Val wheel came in third, one inch behind the second place wheel and four inches ahead of the LGB plastic wheel.

In practical terms, the second, third, and fourth place finishers were virtual equals. The conclusion? If the appearance of metal wheels and the sound they make appeal to you, in most cases the choice between them will involve quality control and esthetics. Only one manufacturer's wheel appears to offer significantly better performance and I hope you understand why we are unable to mention the manufacturer here.

So, in a sentence, San-Val Trains' metal wheels appear to offer better than average performance and average quality at a lower than average price.--RR