gene heskett wrote: > This effect was discussed at length when we made the first 'test' cases for > our tv cameras out of alu we had cad plated back in 1960 and discovered > that no amount of cad plating could protect them from 8 hours over the side > of an LST 50 miles west of San Diego. I am NOT disputing that aluminum oxidizes and corrodes, only that the thin film of oxide is NOT a huge impediment to milling, and that you need to do all aluminum milling submerged in an oxygen barrier. > However, this does lead to the question: > > Is there a calculator, online or downloadable that will tell one the ball > park correct feedrate for a given bit and depth of cut at x rpms? I would > have far less problems with my un-SWAG methods of doing this if I had a > good, known to be safe, starting point. > I have these slide-rule type gadgets from McDonnell-Douglas that I got at a local scrap yard. But, there are some calculators. I have used Mr. Machinst, but I think my trial copy timed out. http://www.mrmachinist.net/ I just checked, it seems to still have the feed rate, etc. calculator.
The basics I use, even without the slide rule, is that plunge should never exceed 1/2 the end mill diameter, and then in softer stuff the feed per tooth should be around .010" per inch of tool diameter. So, for a 1/8" end mill, it should be .00125" per tooth. At 2500 RPM with a 4-flute cutter, then you get 12.5 IPM. For your 1/16" cutter, you should be around 6 IPM for the .030" plunge, but I'm conservative, so I'd keep the plunge to .020" and maybe feed around 5 IPM. Keep the slot clear of chips, so use the minimum of cutting oil if you are not flooding it, and either keep brushing the chips away or blast it with air. The above may sound confusing. What you want to do is keep the chips from recutting. So, either use minimum oil and brushing or air, or a FLOW of some coolant that carries the chips away. Jon ------------------------------------------------------------------------------ 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
