Aluminium Name Plate for truck

I thought I would show my first x carve project in aluminium.

I decided to make a name plate for my mates birthday to go on his classic Mack R series truck, in the stlye of an machine manufacture plate. Using a font close to that used by Mack Trucks.

I still need to spraypaint it and remove the paint from the raised surface, but I was so excited, I just had to share straight away.

I made 2 of them to mount on the chassis on each side of the truck. Here is the second one still on the waste board.

I grabed the aluminium from my mates workshop, a couple of scraps of 190x55x3mm thick 6061.

I split the design into 3 workspaces, the first being the mounting holes, so I could screw the aluminium to the waste board.
The second workspace was a 2 stage carve of the recess (0.5mm deep) and the third workspace was for cutting the outer shape. I ran 4 operations in all.

OP 1 (mounting holes):
2mm 2F EM
FR: 1200mm/min
PR: 76.2 mm/min
DOC: 0.1mm

OP 2 (roughing):
4mm 2F EM
FR: 1200mm/min
PR: 70 mm/min
DOC: 0.1mm

OP 3 (detail):
1mm 2F EM
FR: 1300mm/min
PR: 70 mm/min
DOC: 0.1mm

OP 4 (outside edge):
5mm 2F EM
FR: 1200mm/min
PR: 70 mm/min
DOC: 0.1mm

I did have some chatter, but not alot, I did experiment with a faster feed rate with the detail operation (1400mm/min) but it broke the bit. I am still experimenting with speeds & feeds.
I used a air hose to clear chips and a cheap airpump that only does 20psi, I badysitted the job and brushed out chip with a toothbrush also. I used kresoene as a lube.

Before I did this job, I practiced the 2 stage cutting process in scraps of wood, after about 5 attempts in wood, I was happy with the end result.

After that I practised milling a 2 stage cut in some 5mm aluminium with different feed rates. Once I got that, I then did the name plates in aluminium.

Oh, here is the truck they will go on.

I still got plenty of room to improve the finish. The floor of the cut is smooth, the sidewalls not so much. Any pro tips would be gratefully received.

Designed and tool paths generated in Easel, UGS used to zero in and run the jobs on the machine.
Cheap Chinese end mill bits and a stock x-carve (early version).