On Thursday 24 January 2013 13:15:06 Roland Jollivet did opine: Message additions Copyright Thursday 24 January 2013 by Gene Heskett
> On 24 January 2013 18:27, Gene Heskett <ghesk...@wdtv.com> wrote: > > On Thursday 24 January 2013 11:05:42 Todd Zuercher did opine: > > Message additions Copyright Thursday 24 January 2013 by Gene Heskett > > > > > Add a spring to your contact, to give it a degree of compression. > > > > I did, in a previous design, mount the pcb on grommets so there was > > room for crush. but found it near impossible to get a consistent > > spring back. Or if off center, a consistent restoration to level. a > > 4 grommet mount would have solved that, but the frame of that gage > > didn't have room. So I wound up insulating the pcb being carved in a > > pocket of micarta, and g38.2'd the pcb I was carving, which worked > > very well indeed. > > > > Like T. Edisons & his light bulb, he found 10,000 ways it didn't work. > > > > All my current problems regarding this would go away if the switch > > hysteresis backup move would just do another 5 thou of back away > > anyway if it found the switch open when it checked instead of > > freezing in place and fussing with a big red error advisory because > > the switch was found to be already open as it started the back away > > move. HINT, HINT. IMO, the only error here is in the assumption > > that the home switch is mechanical, with several tens of thousandths > > on an inch, or in metric, possibly a whole mm of hysteresis. Perhaps > > even a per axis keyword to make it work either way? Would seem to > > give maximum flexibility at any rate. > > How about using a proper travel limit switch. The contact operates well > within the first mm, and then you can press it a further 5mm or so with > no ill effect. And on release the hysterisis is very short... > > http://www.galco.com/buy/Eaton-Cutler-Hammer/E47BMS04 > http://www.galco.com/buy/NTE-Electronics/54-438-BP > > Regards > Roland I don't understand why the pressure to use a sloppy microswitch here, when the electrical contact can and is within .0005" repeatable. All this cut, measure, set touch off, try again is a kludge, why not calibrate it dead on? Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) My web page: <http://coyoteden.dyndns-free.com:85/gene> is up! My views <http://www.armchairpatriot.com/What%20Has%20America%20Become.shtml> Be careful! UGLY strikes 9 out of 10! I was taught to respect my elders, but its getting harder and harder to find any... ------------------------------------------------------------------------------ Master Visual Studio, SharePoint, SQL, ASP.NET, C# 2012, HTML5, CSS, MVC, Windows 8 Apps, JavaScript and much more. Keep your skills current with LearnDevNow - 3,200 step-by-step video tutorials by Microsoft MVPs and experts. ON SALE this month only -- learn more at: http://p.sf.net/sfu/learnnow-d2d _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
