Remember, your cut velocity and tool rotational speed must be matched to the material you are working on.
Too fast you may melt plastics or break a bit.
Once you get things working, write down the settings for that particular environment!
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I have been looking into options for clamping stock to the waste board. A guy in Ohio is selling 1/2" aluminum bullet with threaded holes 1" OC for $400.
Luckily the sharpie doesn't care too much about feed and speed. Baby steps.
I use MDF as a sacrificial board.
Next, I level the surface with a 1/4 inch bit.
Paint with clear lacquer, dry thoroughly.
Stick a 1/8 inch sacrificial acrylic panel to the MDF using double stick tape. (replace panel as needed)
Use removable double stick tape to temporarily hold the work while routing to the above acrylic panel.
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How do you deal with dust from the mdf?
The 3/4 inch MDF is there for surface stability only.
You should never cut into the MDF therefore there is no dust.
At most, you cut totally through through the work piece and maybe a few thou into the sacrificial acrylic panel below.
i.e. the MDF is below the sacrificial acrylic panel.
---------------------- <-----<<<< work piece
---------------------- <-----<<<< sacrificial acrylic panel
=============== <-----<<<< 3/4 inch sacrificial MDF panel
How about heavier parts?
Doesn't the leveling of the mdf make a bunch of dust?
Let's say I was carving 3/4 MDF, then I use a vacuum assembly attached around the cutter.
I use a vacuum cyclone like this to get rid of the dust before it enters the vacuum cleaner.
Yes levelling the MDF makes a mess, therefore you need the assembly as mentioned.
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Why do you need to get rid of the dust before it enters the vacuum cleaner?
Have you cut metals withit?
I need to make two small polycarbonate parts from a 0.250" sheet. Which end mill would you use?
The dust is so fine it plugs the vacuum bag very quickly.
If you don't mind replacing bags then you do not need the cyclone.
Since buying the cyclone, I have not had to replace a vacuum bag.
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I have done some aluminum and diamond dragging on brass and glass.
Mainly cut plastics and wood.
TKall:
I need to make two small polycarbonate parts from a 0.250" sheet. Which end mill would you use?
Make sure you take the radius of the bit into consideration. 
If you need 90 degree edges, use something like this:
Thanks Larry.
I appreciate the good advice.
Are those 4 flute?
TKall:
Are those 4 flute?
Yes but two or three would work too.
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Make sure you take the radius of the bit into consideration/quote]
Is this handled in the machine software with end mill selection and offset? I don't have to draw the part differently, do I?
I do everything with AutoCAD so I have to take cutting bit diameters into consideration in my head/drawing. 
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