blackout_89t said:
The holes and slots create stress concentrations in the part.
If the rotor was not designed originally with these holes in mind, then chances are the stress in those area is not safe and will indeed fail in those areas. Especially if the holes are close together and or near the edges of the surface.
well of cores this will happen but if you use a good casted part there will not be a prob to certon dagree
there is alot of tecnogy going into casting
piaa for example they use low perure casting with there cast wheels
casting has come along way since the 80's causeing now you can have nice grain to it and more even though out the steel
look up casting and sucg that shit has come along way
now for the big thing on muching in slots and drilling
the key si to use a good sharpe bit and cold cut aka no over heating
kvr use great methed on cutting there rotors perures air cooling instead of cutting fuild wich works but doe snot as good as air
air cooling takes longer but is way better then cooling then cuttign fulid
in the end if doen right it will last for along time and work great
but any thgin form china stay the fuck away