I was reading this post about surface finish
http://www.cnczone.com/forums/showth...t=36496&page=1 (Surface finish issues on VF3-SS-YT)
and I am very curious about this because I have been wondering about what really separates Haas from other machines.
If you read thru the post on page 3 and 4 there are some pictures and a sample tool path. I ran this toolpath on my 2008 VF-2YT and my 2006 minimill and I got identical results to what Mr. Flat in the post is complaining about. There are .0001" circular marks on the floor of the finished surface that cannot be removed with scrubbing with a scotch-brite pad. In the photos he claims the identical path run on a Mori that the machining marks can easily be removed with a scratch pad. The marks were referred to as "coining" marks that coincide with zero speed changes in direction in x and y. This is not a tool deflection issue or a coolant issue (same results with and without coolant, and with larger diameter endmills running the same program). And if another machine can do it as Mr. Flat claims then it is not a programming issue. The only change I made to the toolpath was to cut .005" deep instead of .055". I measured the "surface finish" with a Federal MasterTest .03" diameter stylus and I think the .0001" measurement is fairy accurate although I admit the test is crude.
What I want to understand is if this is normal for a machine in the same price range. I am willing to accept this if you have to spend double or even 25-50% more to get this .0001" scratch to go away. However if a Hurco, or Milltronics, or Fadal or other similar machines can pass this test then there is something amiss. The construction of all these machines is nearly identical and they probably even use the same suppliers for the motion components so I want to know what's up.
I love my machines and this has never been a problem for me, but now that it has been brought to my attention I would like to understand what is normal and acceptable under these conditions. I don't have access to another machine to test, but I know some people who do and I plan on investigating further.