After experimenting with several brands, I think I get the best performance and value from a Starret bi-metal 10-14 variable pitch blade. That size should work well for your stated material sizes as well.
The place I last bought them appears to be no more (or at least their site is no more) so I'm all ears if you find a good source for them.
GsT
The place I last bought them appears to be no more (or at least their site is no more) so I'm all ears if you find a good source for them.
GsT