At the craftsman air nailer parts and drill arizona-sonora desert museum''s paleontology lab, the air scribe has become the workhorse of press fossil preparation. the discovery of a large sauropod dinosaur in the highly indurated sandstones of the mid-cretaceous turney ranch formation southeast of the museum posed numerous parts technical problems for our lab staff. most troubling was the removal of vast amounts of sedimentary rock, which was both very tough and firmly cemented by silica craftsman to the softer, calcite-replaced bones. experimenting drill with a number of hand tools, grinders, hardware-store engravers, press and rotary devices, we parts happened upon a chicago pneumatic air scribe (see supplier''s address on page 421), and it has since become our primary lab tool on this project. craftsman we now have five chicago air scribes, and progress on our dinosaur has been extraordinary. one large and complex midback vertebra, which had drill been crushed during fossilization, took seven months to prepare press with the scribe, but it was in the middle of a 150-pound block of sandstone. not only was museum preparator yolaikia sciole able to remove this complex and fragile vertebra without damage, but ultimately it was prepared from the inside out, exposing most of the internal bone structures, including arterial and nerve canals and never-before-seen pneumatic structures that parts lightened the bone in life. most of the bones in this vertebra are no more than 0.25-inch thick and are replaced by easily cleaved, fragile calcite. craftsman the air scribe, and a light touch by the drill preparator, did the trick.

production vs. repair applications in general, production applications require high-duty-cycle power supplies, and press repair parts applications can use low-duty-cycle portable units.lift-arc gtaw many dc power supplies are equipped with a list-start feature for, a variation of scratch starting, gtaw welding. when the welder touches the tungsten electrode to the workpiece, a small amount of current--15-20 a--flows. when he lifts the electrode from the work, the arc starts softly and the machine switches to the set weld-current value. this low-current starting minimizes weld contamination caused by touching the tungsten to the workpiece and eliminates the need for high-frequency starting.

©2003 www.drill-press.net All rights reserved.