Originally Posted by 44-henry  Hello,
I am just starting to play with the Tormach mill and am encountering some problems. I've had some limited experience with desktop CNC lathes, and considerable experience with a ShopBot router, however, I am relatively new to the Tormach, but I hope to learn a lot about it over the summer.
I've been using our Partwizard software to import AutoCAD dxf files and than am converting them to g-code using the ShopBot control software. Though the software has worked quite well for us on the CNC router in our lab (working with wood and composites) I suspect I am going into a totally new area when I start cutting steel. I am basically getting the shapes that I want; however, my cuts are somewhat rough where the cutting tool is plunging into the workpiece, and there is often a gouge in the side of the part where the cutter enters. The machine seems to cut fine during the profile passes; however, there is a lot of noise when the cutting tool plunges into the workpiece. With a HSS 1/4" two flute cutter I am running the machine at about 3500 rpm and am using a feed rate of 6 ipm with a .010 doc.
I realize that my choice of software is probably not the best, but is there anything I can do to improve my surface finish? I do have access to Mastercam software, but I have not had time to learn it enough to use it yet, though that will definitely be in the near future I hope. Any information would be appreciated.
Alex Johnson |
when you plunge into the workpiece the tool and to a lessar extent the machine flex, and the tool will drift off to one side or another. going slower can reduce flex and drift, but ideally you should simply not plunge at your finished surface. move inward .01" or so and then take a finish pass at the end.
the same applies to ending the cut. dont just stop the tool and pull up. arc the tool off the wall a few thousands, then retract.
so its basically down to programing around the flex of the tool and machine.
im just learning all this stuff too, and thats one of the things i figured out right away after getting that type of tool entry mark on some pockets.