For this I needed an M2 tap and die set which arrived in the post on Saturday from SFC-Tooling. The body of the mandrel caused no problems and was machined and tapped. The screw on the other hand caused a problem for my first tapping attempt.
I have discovered a technique from Fadmucker for making such small threads. He's made a special die holder with a pre-drilled M2 clearance hole. This means that the die is held perpendicular to the item being threaded.
I've also discovered the following advice on screw cutting from the National Maritime Research Centre who make the point that a thread should have a shoulder if you want to be perpendicular to the load bearing surface. You can see from my diagram above that I do not have such a shoulder, however I don't believe this will be an issue given the size of the screw and mandrel.
My plan of attack is 2 fold, the first is to get hold of some short M2 screws and nuts to check my threads against and the second is to have another go at making the large headed screw for this mandrel.
I've also nearly finished my drill bench which is good because I believe the new pillar drill (drill press) is arriving tomorrow.
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