Cutting 6061 .325 aluminum

[randall_e]

Hi, I have a job of cutting 2' letters in .325 aluminum using 6061. Is 6061 the best alloy to use? What bit and speed would be best? I have a Yaskawa spindle. I was research and the search function but couldn't find what I was looking for.
Thanks

[courtney2018]

6061 is a common use aluminum grade. Very good stuff. In the past when I've cut aluminum on a mill machine I use a speed around 600 to 800 and some cutting fluid at around 1/4" a second, maybe a bit less. Sounds strange, but I use my ear and listen and adjust the speed that way. You can go faster than that obviously, but you'd need some coolant to keep the bit and part cooled down.

I don't know what kind of detail are in your numbers, but I would imagine a 1/4" end mill bit would be fine.