2010/11/18 Dave Caroline <[email protected]>: > enjoy > http://www.shipsnostalgia.com/guides/William_Doxford_and_Sons#The_Manufacturing_Process > > Dave Caroline (archivist) > > On Thu, Nov 18, 2010 at 1:05 PM, Igor Chudov <[email protected]> wrote: >> Which brings up a question. >> >> How did they make propellers for big ships in the old times without 3D CNC? >>
Unfortunately, this link does not really answer, how exactly the propellers were made, because I also think that those curved surfaces are pretty tricky to get. Unless they cast them in molds. But that page had reeeeeeally nice insights, on how some other parts were made. Especially engine cranckshafts. How thick were those blocks that were cut with [probably] oxy-gas? One meter? My waterjet cannot do even a quarter of that thickness. Awesome. Now that is where one would have a job for lifetime to convert ALL those lathes, mills and god-knows-how-they-call-them to EMC2. 2010/11/18 Andy Pugh <[email protected]>: > On 18 November 2010 12:49, Viesturs Lācis <[email protected]> wrote: > > Probably just a hydraulic cylinder with a pressure regulator and pump. > With the regulator set to a pressure where it will almost, but not > quite, lift the gantry the ballscrew torque needed to move the gantry > is equalised. This is likely to make axis tuning a whole lot easier, > and will also significantly reduce wear. > Thanks, that beam weight compensation makes perfect sense! 2010/11/18 Sven Wesley <[email protected]>: > 2010/11/18 Andy Pugh <[email protected]> > >> >> I imagine that the "beam" is a lot stiffer than the "quill". You >> probably machine with the "quill" retracted as far as you can, but can >> still reach down inside things when required. >> >> > Yes, and it's also a speed thing. Accelerating only one part takes time > because of the weight itself, if both moves it goes much faster. > Could be. I would love to see this beauty in action - I can't really imagine, how a Z axis movement speed might be an issue in a 250-ton machine. This machine is out of the world that I am used to live in :)) /vie ------------------------------------------------------------------------------ Beautiful is writing same markup. Internet Explorer 9 supports standards for HTML5, CSS3, SVG 1.1, ECMAScript5, and DOM L2 & L3. Spend less time writing and rewriting code and more time creating great experiences on the web. Be a part of the beta today http://p.sf.net/sfu/msIE9-sfdev2dev _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
