|WikiProject Metalworking||(Rated C-class, Top-importance)|
|WikiProject Technology||(Rated C-class)|
The main category for this article is category:machine tools. This cat is a sub-cat of Category:Industrial equipment, Category:Machines, Category:Machining, Category:Tools, and Category:Woodworking; therefore this article does not belong in any of those categories because it's main cat is already a sub-cat. If we added the higher-level cats to all articles, most articles would have at least ten categories and each category would be un-navigable. Wizard191 (talk) 12:57, 12 October 2009 (UTC)
- A related category that readers may find interesting is Category:Machine tool builders. — ¾-10 23:57, 24 January 2010 (UTC)
"From the simplest to the most complex, most machine tools are capable of at least partial self-replication, and produce machine parts as their primary function."
Forging hammers, etc.
Are forging hammers (i.e. power hammer, trip hammer, etc.) machine tools? My gut says no, but I could see the other side of the story. If not, we need to clarify why in the article. Wizard191 (talk) 19:43, 26 May 2010 (UTC)
Too much nomenclature, not enough history
There's far too much fussing over nomenclature in the article, and not enough history.
The classic machine tools are the lathe, planer, drill press, grinder, and milling machine. There's good history over at lathe, milling machine, and planer. An important historical point is that good milling machines didn't really appear until the late 19th century and didn't really get good until the Bridgeport in the 1930s. Before that, heavy machining was limited to flat surfaces (planing), round surfaces (lathe work), and holes (drilling). Casting could produce almost any shape, but if a large surface had to be finished, it had to be flat, round, or a hole. This shows strongly in steam locomotives, where all the finished surfaces on big parts are flat, round, or holes. --John Nagle (talk) 06:57, 10 September 2011 (UTC)
- You're completely right that the current state is imbalanced—but it's not because there's too much nomenclature (in absolute terms), but rather because there's too much nomenclature compared to the other content that's still missing (that is, in relative terms). I have been back-burner pondering a history of machine tools article (or at least a history section of the machine tool article) for about 4 or 5 years, but it's a large undertaking that will require more time than I have to donate anytime too soon. The nomenclature info that's here has to remain here, because it deals with the question of what a machine tool *is* (or isn't), that is, which subclasses of machines fall into the class of being machine tools. The reason this has to be dealt with is that encyclopedia articles start off by stating what a thing is. Which for machine tools turns out to be a multivariate analysis, as the existing nomenclature info shows. But you're quite right that plenty of content on the archetypical machine tools has already been written and currently exists as sections of other articles on specific machine tool types. In fact please see the details in a musing of mine on this very topic at User:Three-quarter-ten/Ponderings#A "History of machine tools" article: first glimpses of making it actually happen. We will improve this coverage within the next 5 years—just need to find time to do the writing and revising work and nailing down the inline reference citations. — ¾-10 15:46, 10 September 2011 (UTC)
- I read a very good book on the history of machine tools, but I don't remember the author. There is quite a bit about the early history in One Good Turn by Witold Rybczynski. I may be able to insert some of that here. Critical steps were a lathe that turned a screw more accurate than its own drive screw, and rubbing three surfaces together with abrasive to get flat surfaces: two surfaces can match as convex and concave spheres, but three in all combinations match only if all are flat. Rybczynski Says that a steam engine cannot be made by hand. That is not strictly true, but it might take less labor to supply the power by turning a crank. Rybczynski is extensively referenced in the screw article, but not the part about early history of machine tools. David R. Ingham (talk) 06:46, 17 March 2012 (UTC)
- The making of true plane surfaces are described in Roe(1916) and I believe they were used in Maudslay's shop. The shop had several which workers could use for checking their work. The method in which they were made is lost; however we know that it used scraping and not abrasives.Phmoreno (talk) 12:19, 17 March 2012 (UTC)
- True, the 3-plate method is one of the many things that a history article will talk about. Hand scraping is one of the most important cutting methods for it. I recall from my reading that scraping by the 3-plate method was used by Joseph Whitworth, and I think I recall that I've seen it credited to his invention, although that crediting may be wrong. His shop, and many since then, used it to generate highly accurate surface plates; and accurately flat machine slides (dovetail slides, lathe ways, and so on) were thus possible to make, scraping them to a bearing using the plate as the reference surface. Speaking of hand scraping, Wikipedia's article on it is currently very underdeveloped—that's another thing on my long-term to-do list (long-term being, in this case, probably a few years till I get around to it). There is (and has been for over a century) a lot of discussion and confusion out there in the world about the relationship of grinding and lapping (abrasive methods) to hand scraping. For example, questions like, does one obviate the other; is one more accurate than the other; etc. The answer is actually a multivariate relationship that most people oversimplify; both are capable of high accuracy under appropriate conditions, both have their place, and neither is obsolete. Doses of reality on the topic are given in Colvin 1947 (pp. 269–272) and also in an excellent series of articles by Michael Ward that has been running in Home Shop Machinist in recent issues. Colvin felt the need to rant about the folly of some people believing that no surface could possibly be accurate unless it was hand-scraped, and he cites machine tool builders that proved them wrong ... Ward, on the other hand, very rationally provides some arguments that support the idea that hand scraping is not at all obsolete and in at least some cases can correct inaccuracy left behind by the grinding op (although the question behind that, to my mind, is whether the grinding [including workholding] should have been done more skillfully/knowledgeably, and Colvin cites examples where it apparently was). Ward's articles are highly readable, and cite a monograph that I myself haven't gotten yet, Machine Tool Reconditioning by Edward F. Connelly. Anyhow, a digression ... one very good book on the history of machine tools is Rolt 1965. Maybe that's the one David remembers reading. It is very readable. Woodbury's monograph series from circa 1955-1965 (republished as a set in 1972) is another of the most important references. In fact, a good bibliography is already underway at Machine tool > Further reading. I should add Rybczynski 2000 there—he provided more info about the special-purpose automatics of the hardware industry than even Rolt or Woodbury provided. One of the frustrating things about this history is how relatively few good books have been written about it, and how each author managed to miss entire segments of industry—you have to read across many authors to start to arrive at the real, whole truth. But that's not their fault, as pondered here; each did his level best. Anyway, glad to know that you guys are interested in developing Wikipedia's coverage on these topics. We will chip away at it in coming years ... — ¾-10 18:10, 17 March 2012 (UTC)
NBER definition of machine tool
The NBER's 1930s definition is probably out date. It was used as an industry classification. Perhaps someone who is familiar with industry classifications can supply the modern definition.
As for the part of the definition about "operating other than by hand power" it should be pointed out that the many early, true machine tools were in fact hand powered, as clearly shown by the drawings.
It is also worth noting what Henry Ford said about electrification allowing higher cutting speeds and that without electrification there could be nothing like what we know as modern production.Phmoreno (talk) 18:12, 19 November 2011 (UTC)
- Forgot to follow up on this thread. The first two points mentioned above have since been addressed via edits to the article. Regarding the third, it's an interesting topic, and actually rather complex. It's amazing how technologically advanced some people were in the period of the 1880s through 1920s despite electrification not having spread very far yet (especially rural electrification). Line shafting can seem rather primitive today, but there were some remarkably advanced machine shop capabilities, and other manufacturing capabilities, in the days when the motive power came from a belt off the line shaft and the light came from an expanse of windowpanes (during the daytime) and oil lamps (when the midnight oil needed to be burned). Certainly, though, it's true that today's technological milieu would never have taken shape without electrification. — ¾-10 18:32, 17 March 2012 (UTC)
Planning new section-machine building before machine tools
I'm planning to add a short section on machine building before the widespread availability of machine tools. Hunter provides some good descriptions with first hand accounts in Steam Power.Phmoreno (talk) 18:01, 15 May 2012 (UTC)