[VSO]

Anyone experienced hard milling a material like C45? I am having troubles with a new job in shop. Simply a part has more milling process rather than turning. Using 8 mm solid carbide chatter free iscar endmills. 3 mm depth of cut generally. Doing side mills also. I prefered doing down milling coz the mill was chattering a lot in up milling. I am also using a long guide bush to make the part stable enough. 2500 rpms and 450-500 mm/min feed for roughing and 3500 rpms and 600-800 mm/min feed for finishing applications. The guys here telling me to give more rpms and feed :nono:- i tried to give a little more but chattering problems began - but swiss machines are not that stable like vertical milling machines! Is there anything wrong with it? Or am i just havin a brain fart? I am trying to optimize the tool life and cycle time..The part has 12 mm of diameter and with 60 mm length. And i cannot do a sync with sub spindle because of the part's geometry. The machine is 20mm hanwha. Any ideas for a better tool life?

[carmstrongls1]

many times I have problems like that I go with a 3 flute mill. vs. 4 flute. Then decrease the rpm and increase the feed. But one question. Are you facemilling or cross live tools? When hard milling I would use Kennametal cutters vs the iscar stuff if possible. You would be amazed at the grades of variable helix Kennametal cutters they have. WE use them milling inconel on the swiss machines with great results here.

[VSO]

I do both face and cross live milling. Generally no probs with face milling, as the sub spindle is powerful than cross live tools. I will now investigate Kennametal's stuff.. I now prefered to lower the rpms and give the feed a little bit more. It looks like much more stable to me. Thank you anyway, the thing i did not get is, did you get better performance in 3 flutes?

[carmstrongls1]

I do both face and cross live milling. Generally no probs with face milling, as the sub spindle is powerful than cross live tools. I will now investigate Kennametal's stuff.. I now prefered to lower the rpms and give the feed a little bit more. It looks like much more stable to me. Thank you anyway, the thing i did not get is, did you get better performance in 3 flutes?

Yes, with the 3 flutes you get more cut because the helix allows more broad and deep removal. each flute gets a worload that in a sense simulates greater feed or allows for more area of chip to fill. I use the Mitsubishi M star 3 flutes alot on 316 SS and nitronics. Recently I had an application with an IMCO 4 flute 1/16" mill on the subspindle face milling slots. at 5000 rpm .02" depth of cut and 2.5 ipm (.06 deep solt) I could only get around 70-75 parts cut. When I changed to the three flute I now get 2000 pcs each mill. Also at 12.5 ipm feedrate.

getting the material out of the hole with feed is commonly the best practice. Unfortuanately with the swiss machies we only get one shot to do it So we'd beter do our homework.

[hacdlux]

if I'm ripping out material my preferred em is the Niagara elite 5 flute you can get them in stub and with a corner radius

you get limited on your doc because it has small gullets but you can generally go pretty aggressive on the feed which helps keep the chatter down.

and ive used them in the bridge port when i had to modify some chucker tooling
that smoked a hss em in under an inch

[VSO]

I worked with nothing but swiss so far. I am not really experienced in tough milling applications, we got very easy milling jobs so far.. But this one is a little bit tough. This is why i stuck. People here mostly say that a solid carbide end mill with corner radius or chamfer, wants to chatter more than the non radius ones. But weirdly, i simply got better performance in corner radius end mills? Using a 3 flute end mill also a good idea; i bought a variable pitch, non radius 4 flute endmill here from a local producer..Bunch of .. whatever, it did not even able to make 10 pieces, cracks came out at the hellis just after three pieces. However, the last set-up i made is looking good so far, although i had given 1800 rpms to the roughing end mill.. The cutting process now sounds good, no chattering or something else. I will give a try if i could find Kennametal products and a good 3 flute end mill.. I love swiss machines but the worst thing is they are not as powerful and rigid as cnc lathes.. And mostly adviced speeds and feeds by the manufacturers does not fit swiss machines..