Newbie- General help with cutting aluminum??????

[lilbs67]

Hello,
I’m pretty new to the world of machining and need several tips on cutting. I’m having difficulty understanding proper feed rates and spindle speeds based on which cutter to use for different types of stock materials, should I use 2 flutes 3flutes or 4, center cutting vs non-center cutting. How to achieve a nice finish on the final cut. I have a Proto Trak SMX DPM2 full 3 axis CNC mill. For my cad I use Solid Works and cam Visual Mill. As example below I am cutting a 18”L x 4”W x 1” thick aluminum stock. Any input would be greatly appreciated. I added a bmp file pic to show part.


Stock material (Aluminum)

.375 cutter/2 flute/HSS/TICN coated

4000 spindle speed

Plunge 15 in/min

Approach 15in/min

Engage 15in/min

Cut 20in/min

Cut direction (mixed)

Step distance 35% of tool diameter

Z total depth of cut .275

Z incremental cuts .0825

[ImanCarrot]

2 flutes is good for aluminium.

Your change in direction means that on some cuts you're "climb" milling and on others you're "conventional" milling. The latter will wear your tools quickly and give a poorer finish that the former.

I'm kinda new to the speeds n feeds stuff too, so perhaps someone else will chip in?

Oh, coolant? what coolant are you using? bear in mind you're trying to get all the chips away from the cutting face.