Hello,

I will try to make a guitar neck out of 70x35x100 mm piece of 7075-T6 aluminum.

I have 10k-30k rpm Kress milling motor installed on DIY MDF CNC machine with keling 425 oz-in steppers. Max feed rate that I can achieve is 600mm/min.

Machine is not very rigid in my opinion. I tried to cut 2mm thick aluminium in one pass and got it running in one direction 250mm/min @ 10k rpm with 6mm single flute endmil, spraying WD40 over the endmill every minute or so. I got into 'standard' aluminium chip gumming problems, but the real problem was cutting in the opposite direction, where machine started jerking until I reduced the feed rate. At certain point i had to reduce the feed rate down to 10mm/minute for the back-x and back-y direction. Once x direction changed again I could increase the feed rate to 250mm/min again. That tells me that I (probably) havent destroyed the endmill, but maybe have problem with fastening the milling motor tight enough...

I will have to buy endmills for doing this new project. I was thinking about getting the fly cutter endmill to do rough cutting of straight parts, U shaped or Ball shaped endmill for shaping the oval parts (eg. back of the neck) and ?-flute endmill for cutting.

What kind of endmills would you suggest I should use in a sense of shape/size, number of flutes and the material (HSS/Carbide), and regarding to that - RPM of the milling motor and pass depth ? And are there any considerations about different endmills for roughing / finishing ?

Also, I still haven't figured out how I'm going to do the headstock which is under 7 deg. angle. I was thinking in doing that last, and securing the billet under 7 deg angle, so I can work on headstock like it's straight. Any ideas on that would also be very helpfull.

thanx