On Tuesday, February 14, 2012 12:53:29 AM Mark Cason did opine: > On 02/13/2012 10:03 PM, gene heskett wrote: > > On Monday, February 13, 2012 10:21:08 PM Jon Elson did opine: > >> gene heskett wrote: > >>> Guy's, maybe I don't understand cutting alu as well as I thought. > >>> > >>> All along, I have believed that it was more important to keep the > >>> oxygen in the air away from the cutting surface in order to slow the > >>> formation of alu oxide on the surface, which in normal air, not > >>> blown, can get a good start in 0.001 seconds > >> > >> I have some doubts about this. The oxide will form unless you run > >> under Argon shielding, > >> which may not be real practical. > > > > Nitrogen should work equally well since the idea is to flood away the > > oxygen. And its 99% cheaper. > > Not exactly, Nitrogen can react with the magnesium in various > alloys, There's a reason why noble gases, specifically Argon, and > Helium are used as shielding gases. The only exception is CO2, where > it's used in welding.
There, particularly in a mig setup, its main reason is to add its carbon to the puddle, hardening the weld. Same effect as firing up your Smith Wrench and running a long central feather in the flame by reducing the oxygen flow a wee bit. You can make very very good welding rod out of a pile of coat hangers that way. ;-) But you don't have the control over the carbon added that way in comparison to the Smith Wrench, that is almost unlimited. 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> Support your right to bare arms! -- A message from the National Short-Sleeved Shirt Association ------------------------------------------------------------------------------ Keep Your Developer Skills Current with LearnDevNow! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-d2d _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
