Gene Heskett wrote: > Greetings; > > One of the things I have not yet learned is how to get the most swarf from a > given milling tool. I have a tendency to go slow, so the swarf is sometimes > so thin it settles like snow flakes when it is blown away from the work. > > Obviously this is wasting the cutting edge of the tool, dulling it > prematurely. > > So when my fresh shipment of 1/8" mills gets here, I would like to be able to > have it throw thicker chips and far fewer of them but remove lots more metal > before they dull. > > I'm going to rig me an oil squirter from an in tank auto fuel pump to try and > keep the mill wet. With a tuna can under the workpiece I can catch most of > the runoff, and maybe even filter & recycle it. Details to be invented yet > in the finest of shade tree mechanic methods of course. ;) > > Assuming I keep the area wet with cutting oil at a high enough flow that I > don't wind up with a muddy slurry, but do have enough chips to act as a wick > and keep the mill wet from the cutting oil they absorb (or the oil level in > the tuna can is high enough), and the 1/8" 2 flute carbide upcut spiral mill > is turning 2500 rpms, how fast can I feed it while doing a 0.020" deep cut > per pass without breaking it? Slower and deeper, or shallower and faster for > best tool life? > > Feeds and speeds as you already know is a delicate dance with what material you're machining, spindle speed, number of flutes on your milling cutter, table speeds and lubrication. And like you discovered above, it's better to cut than rub your material off.
It sounds like you are running a smaller machine. If that's the case, another factor comes into the equation and that's how stable or rigid your spindle is. A spindle that is built with bearings less than ABEC 7's is not going to give you the rigidity you will need for long tool life. Your small spindle my wind way up, but that'll be useless when you start to load it with heavier cutting. Procession is not your friend. Even if it's so small, you can hardly detect it. I like your oil squirter idea for lubricating your cutter, but I want you to consider instead using a spray mister. The reason is simply because once you start to make bigger chips with those tiny cutters, you're going to have a problem with getting them out of the way. The smaller cutters are more commonly broken because the chips clog up the works. A spray mister will by its nature, blow everything out of the slot you're cutting, keeping the system cool, lubed and clean. It's less of an issue with larger cutters. The mister does make more of a mess, but with simple and carefully placed shielding, you can contain most of it. You will also be surprised at how little mist coolant you'll end up using when you get it adjusted right. My worthless two cents. ;-) David ------------------------------------------------------------------------------ Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day trial. Simplify your report design, integration and deployment - and focus on what you do best, core application coding. Discover what's new with Crystal Reports now. http://p.sf.net/sfu/bobj-july _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
