What is the general thinking for using a shell mill in aluminum?
http://www.jlindustrial.com/NSM-0999...D/product.html
The tool is Cobalt and 2.75" with six flutes. I cut my hand a bit taking it out of the package so I know it is sharp []
So this weekend I plan to try some cuts. Basically my goal is to make a very smooth finish for the face of a part. The shell mill is big enough that I can finish in one path. I only need to remove .07" from the stock.
This is now the biggest tool in my collection. What type of feed/speed should I use with it? I have been using max RPM for all my tools so far since I only get 3k from my spindle. The biggest tool I used in the past was a 1" roughing EM and it cuts well at 800sfm with .007" fpt with good result at .5" depth and 45% step over. For finish pass I was using a .75" tool at .0025" fpt and was fairly happy with the result. I had some lines to buff out by hand but all and all the result was decent. My hope with the shell mill is that I can cut faster and produce a finish that does not have lines that need hand buffing.
Here are the questions?
1) Feed/speed
Can I push it beyond 800 sfm how about my fpt? Basically I want a smooth finish but I also want to know what the speed limits for the tool is (in 6061).
2) How much material can I remove per pass?
In the past I have used 1/2 of the end mill size as a rule of thumb. Would this still apply? I am assuming that HP will be my limit. I need to do the math but if anyone has a guess that would be helpful. I have 5hp spindle drive.