If you pull a big enough chip the heat goes with it... too small you gall. Flood does help.
JT On 9/24/2016 1:26 PM, Gene Heskett wrote: > On Saturday 24 September 2016 12:11:34 Jon Elson wrote: > >> On 09/24/2016 03:04 AM, john mcintyre wrote: >>> Good Day All, >>> Problems with machining sticky material. >>> I find wd40 or crc penetrating fluid in the pressure pack and use >>> the fine tube nozzle to direct the spray right onto the cutting tip >>> . >>> This is good for all sticky materials as it stops the material (soft >>> aluminium) building up on the cutting edge. >> The best fix for this is to keep the tool moving along the >> workpiece. Don't take a deep cut slowly, take a light cut >> and keep the feed rate up. This prevents localized heating >> of the workpiece material. Also, I don't use any plain HSS >> tools, I use M42 or higher Cobalt HSS, which keeps a sharp >> edge MUCH longer. For the small stuff, I use 1/8" solid >> carbide end mills, these work really great. >> >> Jon >> > And for alu, if the spindle can do it, all the rpms it can muster. > This reduces the time between the passage of a cutting edge for the oxide > to form on the freshly cut surface before the next cutting edge comes > by, as does some spray misted, oxygen free oil (safflower is nice) to > keep the surface sealed behind the cutting edge as much as possible. > > That alu oxide forms behind the cutting edge in free air in about 1 > millisecond, and its the 2nd hardest substance known to man. And its > that oxide that eats our tools for lunch. Even carbide succumbs > eventually. > > For long jobs where the work gets hot? A goodly portion of that heat is > from the chemical reaction of the alu burning and forming the oxide on > its freshly cut surface. Reducing its access to the oxygen in the air, > or in the water mix you may be using for coolant, will cool the > workpiece by a considerable amount. > > Messy in the shop, but your tooling will thank you by lasting many times > longer. You don't need much oil, but you do need enough continuous air > to feed the mister. If you can see the oil spray, thats way too much. > An once an hour is enough to make the shop air foggy if not vented > outside. Hard to get off your glasses too. >> ---------------------------------------------------------------------- >> -------- _______________________________________________ >> Emc-users mailing list >> [email protected] >> https://lists.sourceforge.net/lists/listinfo/emc-users > > Cheers, Gene Heskett ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
