Rinsaikeru wrote:It really isn't that expensive--companies change packing size all the time--usually to slightly smaller amounts when they jack up the price per unit...
A full conversion to metric is going to be bloody expensive. I used to work at a mechanical testing lab; here's some of what would be involved in coverting to metric:
Converting the 10-ton and 30-ton presses to output mechanical stress in kilograms rather than pounds would be easy: the actual measurement is in ohms, and the software is already able to convert that to metric units. The 120-ton press would be harder: it dates to 1943, and the analog-mechanical plotter still uses vacuum tubes. You'd need an electronics guy to open it up and rewire the gain circuitry with the new scaling factors. Estimated cost: $1000 plus re-calibration for the 120-ton press, free for the others.
The extensometers for measuring mechanical strain are a different matter: they're built with half-inch, one-inch, and two-inch gage lengths, and it's physically impossible to change them. You need to replace all four. Estimated cost: $50,000 for replacement and calibration.
But the presses are still built using US customary parts, and these break on a regular basis. What are you going to do twenty years down the road when one of the half-inch bolts holding the load cell down shears off, and nobody makes replacements any more? Replacing the 10-ton and 30-ton presses would run around a quarter-million dollars each; the 120-ton press would be close to half a million.
What about hardness testing? I don't know what the metric standard for hardness is, but I'm fairly sure that a machine for testing Rockwell hardness can't be converted: the different standards use fundamentally different techniques for measuring it. Four automated hardness testers at $25,000 each: $100,000; one elevated-temperature hardness tester and furnace: $50,000; if the computerized microhardness tester (it does both Vickers and Brinell) needs replacing, $100,000.
The fatigue lab has six axial fatigue testers, eight rotating-bending fatigue testers, and three low-cycle fatigue testers. Cycle counts are the same between customary and metric, but the stress loads aren't. Further, since almost all fatigue-testing work was done for US-based automobile manufacturers, the custom-designed control and data collection software can't handle metric: $10,000 for new software, plus the cost of re-calibrating seventeen machines.
Replacement parts for the fatigue-testing machines would be even more critical. Since these machines are designed to see how fast parts wear out, they themselves wear out quickly: it's rare to have more that two-thirds of them up at any given time. Replacing the entire lab would probably run around $1,000,000-$2,000,000.
And then there are the miscellaneous bits: the gage-mark punches calibrated at half-inch, one-inch, and two-inch sizes, the calipers and micrometers that use inches, the threaded inserts for bolt testing, the end plugs for tensile testing of tubes, the calibrated five-pound sledgehammer for dealing with recalcitrant parts, and so on...