Today I was the grass hopper.

I have a big (70kg) old MAS dividing head. There s a plate on the spindle that has 3 circles with different numbers of holes for doing quick, simple indexing. However mine is missing the indexing pin/plunger arrangement.
So, as a make work for myself, I've been mucking about on and off for a couple of months making an indexing pin assembly. I haven't seen an original but the design is pretty obvious.
I decided to make it out of brass because I had a lump of cast brass that was big enough to use. So I've been machining down to size and I noticed a very, very fine shrinkage crack in one side of it.
I thought it would be ok as there's not much load on this thing, however when I drilled the 10mm hole in it for the plunger and started making a slot for the release pin today, it must have released a lot of stress in it.

brass crack.jpg

Oops. At least the crack opening up has made it easier to scrap after the "miscalculation" I had milling the slot.

Geez it was nice to machine some brass again after years of not doing so.

Peter
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