On Wednesday 24 August 2016 04:35:01 andy pugh wrote: > On 24 August 2016 at 04:22, Gene Heskett <[email protected]> wrote: > > What occurs when it has come back from there? Or is at a great > > distance from the trip generator? Or am I back to 59 cent roller > > microswitches? > > I have been using: > http://www.ebay.co.uk/itm/351757900525 > (That'as 8mm dia, 1mm distance, there are also 12mm and a range of > sensing distances. Just make sure you get the NPN version and one > where the threaded body goes all the way to the end (shielded type) as > those can be conveniently embedded in machine slides, like this > https://goo.gl/photos/M4zAigRExWFXh5m48 (the prox lurks in the hole > just to the left of where the ball-nut mount is)
And you are sensing the crossfeed slide as it comes across the top of it. Neat. You can go by it w/o demolishing it. Accuracy so far? Whats the X range? And that looks as if the nut is constrained by not clearing the top of the beds V ridges. The screw I am using is pretty small, an 8mm I think, and the bottom of the nut carrier clears the top of the V ways by 10 thou or so, giving me a huge X range since its a 13" screw. I'll likely trim it some. I am currently as I sit down to do it, putting in some set screws to lock that teeny ball nut into the holder, and to forceably compress the nut from one end of the holder to remove the thou or so end play it has now. I don't think I'll worry about a rear end bearing on this small a screw. The "little monster" is current turning about 90 revs, carving a cone shape on its own compound replacement cast iron block, centered on the QC's mounting stud hole. At .25mm's a pass, properties says nearly 1300 minutes, but I turned the feed rate up to 200% while its just working on one outside corner. That may not be enough clearance to carve the similar block for this Sheldon. It needs to be cut in a hollow ground profile for full workpiece clearance, so I may have to byte the bullet and hack up some math. We'll see if thats enough for the time being. But this should remove some of the weight thats swinging offcenter, so the next cut to hollow it out will not take so long as I can crank the revs up above its natural dance on the floor frequency. :) > But these might be more convenient in some situations. > http://www.ebay.co.uk/201633292943 Page is gone, expired. Thanks Andy. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
