MIC-6 is particularly gummy when machining. I always use coolant and I still get a little bit of chip weld if things aren't just right.
Getting the chips out of the slot you are milling is also critical. I would keep using the compressed air blast and i would probably use a HSM slot instead of a conventional slot to allow more room for chip evacuation. It will take more time but should provide better results. I get similar results to John for feeds and speeds. Use 1/8" DOC, 2 flute 24k rpm and 119 ipm feed gives .0024" chip and about 15-20 lbs of cutting force. Jim On 2/21/2017 10:53 AM, John Thornton wrote: > The key to milling aluminum dry is cutting a chip big enough to pull the > heat out with the chip. So big chips mean the part stays cool, and small > chips means the tool will gum up and stick the aluminum. I like 2 flute > carbide from Lakeshore Carbide. They make end mills for steel and > aluminum that have different coatings. Looking in the Lakeshore Carbide > book they recommend for aluminum 1600-2000 SFM ( I assume that is with > flood coolant) and 0.003" inches per tooth. Using my handy calculator > and using 1600 SFM for a 2 flute 1/4" end mill I get 244446 RPM at 146.7 > IPM. > > JT > > > On 2/21/2017 9:34 AM, Todd Zuercher wrote: >> I am a wood worker in a large wood working CNC shop. But I need to mill some >> aluminum for a project (a jig for another process in our company) but I know >> next to nothing about milling such material. What I need is to cut a large >> grid out of a 5ft x 10ft sheet of 1/4inch thick MIC6 AL. The machines I will >> have to do this are large wood working cncs with flat vacuum tables. We >> normally cut flat sheet material like MDF or plywood on a MDF fall-board >> (vacuum sucking right through the fall-board (holes, no jig tape, just >> porous MDF) These machines have no provisions for coolant Just compressed >> air blast and dust/chip collection (big centralized dust collector system). >> I will obviously have to disable the dust collection, because I'm pretty >> sure the local farmers who pick up our dust won't appreciate AL shavings in >> their cow bedding. The machine I am probably going to use has a 12kw 24krpm >> spindle. I would like to mill this with a 1/4" 2 flute carbide end mill. >> Should I use an up or dow n spiral cutter? What feed speed and RPM would be appropriate? What depth of cut per pass? Do I need to arrange some sort of mist system for cooling? What to use and how much liquid in the mist? (Don't want to cause problems with the MDF fall-board or vacuum hold down system.) The grid is only going to be about 2 inches wide, with 12 windows in the 5x10 frame (a lot of wasted material). At this point the plan is to set the milling up with lots of bridges to hold the grid to the scrap then go back and trim those off with a final finish pass. >> > > > ------------------------------------------------------------------------------ > Check out the vibrant tech community on one of the world's most > engaging tech sites, SlashDot.org! http://sdm.link/slashdot > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
