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Tooling and Machines:

1. 1/8" Coated Carbide 3 4 Flute End Mill for Stainless Steel (McMaster  8883a11)
2. Mill (At least 5000 rpm and set up for mist of or flood coolant)

Fabrication

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For the slots, using a slot saw works fine with phenolic and aluminium. But for stainless steel, HSS tools performs very poorly and it's better to do the slots with an end-mill.

I. Making the Blanks

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1. Get sheet stock that has the thickness of the final leading edge.
2. If you have not used the waterjet before, ask for help.
3. From the CAD model, make a .dxf drawing of the part. Check dimensions.
4. Using the related Waterjet software, copy-paste and orient the part such that you can get as many parts from the stock as possible. Make sure that all of the pieces fit in the frame of the stock.
5. Check settings related to thickness, material etc., make sure they are correct.
6. Follow the procedure for waterjetting. After getting the first piece, make sure dimensions are correct.

II. Machining the Slot

1. Break all edges. 
2. Secure the blank in the vise. 
3. Set the speed to 5000 rpm, the feed to 9 15 ipm. 
4. Turn on the coolant.
5. Plunging 1/16" at a time, cut the slot. Power feed is your friend.
6. Once you have reached the desired depth, test the slot width with the Fin Preform. Run .005" finishing passes until it fits snugly. 

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