[ZZII 527]

By some twist of luck, my steel came early this morning AND I was able to get 20 minutes on the waterjet. So I now have four A2 tool steel 56mm carriers, which are about the same hardness as the originals but can be treated to pretty much anything from C20 to C40. I will probably shoot for C23 for now to match the current shaft.

My dimensions were as the drawings say, except:
a) I went tighter on the double-D: 0.470in (11.94mm) radius and 0.350in (8.89mm) flats. With the taper from the jet, this seems to be a good press fit, but may require some filing.

b) The pins will be press fit in the other direction, against the taper of the jet, so I just made their holes extra small, 0.150in (3.81mm), and I'll drill them out later.

The stock I used is McMaster part #9019K147, 18"x2"x5/32" A2 tool steel, but I wouldn't recommend it unless you have heat treating capabilities, since it comes soft (B89-99). I am just using it to have an adjustable hardness to play with.

In the attached picture, the two carriers at the left are the originals (1CIM, 12:1) with almost no visible damage after "mild" usage. The four at the right are the new A2 tool steel ones that I will try to harden to C23 for testing.