We machine all types of Aluminum including the alloys in OP. The ESPI Metals paper is a good general guide to speeds and feeds, Though not the definitive numbers you want. Very definitive numbers are generally available from you tooling supplier. Machining dry does present some problems so we tend to use cold air (Vortec or Exair)on the tool until the final passes. We tended generally tended to lighten up on the feed when machining dry to prevent small burrs.
When weren't require to use a specific coolant made by one
of our divisions the machinist tend to use the Tap Magic Products.
We dry machine a very large number of 36" dia end plates made from injection molded 356 Al. If we use lubricant one of the best lubricants for marching this alloy was a 50/50 mixture of kerosene/lard. In fact this mixture is good on all Al alloys but is a little messy and fire hazard according to our safety department.
I have been in the coolant business for more than 30 years so in general I believe that machining wet is best but having said that a lot of Al is cut dry.
It is typically done at very high SFPM using diamond tooling and don't skimp on the quality as the quality of the tools will translated directly into the surface finish and residual stress in the finished part.
If there isn't some over whelming reason to run dry you would be a lot better off with a good high performance coolant with the appropriate EP additive package to control built up edge it will give you better machining performance with conventional tools e.g. taps etc. and make chip handling much easier.
The H&S arguments about wet and dry are largely academic. if you run wet there is the possibility of coolant mist and if you run dry you will find all the gasses that are found in a welding booth.
There seem to be a number of comparable units on the market these days.
Tooling is a mix of DLC and ZrN coated micrograin carbides along with some diamond coated mills. The best geometries on the market right now are typically not available in diamond though, as much of that tooling is marketed towards graphite machining.
For heavy removal "peeling" operations utilizing high axial depths with lighter radial engagement angles, standard DLC or ZrN works admirably. In fact, it's the best choice in that scenario.
Speed and feed? How much speed you got? Short answer: Whichever speed allows one to achieve the greatest metal removal rate. Start with the manufacturers recommendations and test to find the most stable cutting conditions for your system; ie. spindle + toolholder + tool + tool gage length. 3-flute end mills also tend to work within the natural frequency of a system, so they're always going to be first choice for maximum MRR. The rules change a fair bit at spindle speeds in excess of 15k rev/min and when employing longer length/diameter tooling, which seems to be standard fare in aerospace machining.
