As an alternative … you could chuck the pin in a collet on the [watchmaker’s] lathe and use a filing rest.

But that, of course, assumes that you would make them before fitting to the wheel.

Oops !

MichaelG.

May be easier to drill the hole pattern on a scrap disc of metal and slip over the assembled pinwheel and then just do a series of radial cuts rather than having the possibility of the wedge coming loose

Mount the whole thing in the lathe and index the spindle so you can move from one pin to the next. Grind the flats with a diamond disc in a cross slide mounted dremel or similar. It will probably help to file the pins roughly to size before installing in the pinwheel and use the grinding operation as a finishing operation.

regards Martin

Perhaps a daft idea, but here goes. Pin wheel on an arbour in a chuck, filing rest set up with both wheels outside the pin wheel and the file overhanging. Keep file in contact with rear roller and keep filing till it touches the the front one

I’ve made something similar in the past. Pins were high speed steel and glued into the holes in the wheel. Wheel was mounted on a mandrel in the lathe, with headstock indexing attachment fitted. The flats on the pins were then ground with a thin disc type grinding wheel in a toolpost mounted spindle. Worked well.

On 28 January 2024 at 12:10 Peter Cook 6 Said:

On 27 January 2024 at 20:49 speelwerk Said:

Why not use 0.5mm pivot steel instead?  Niko.

Not sure grinding is as appealing. Z control on my little SX1 mill is less precise than I  would like for 35 repetitions of the same amount ground off. Locking Z tight and cutting at the same height with the saw looks a better bet.

Thanks again for the ideas.

That’s why if you did grind the pins you should lock the cross slide and take a lick of all the pins at the same setting indexing round as you go. (Hence my suggestion that  you reduce the amount to be taken off by filing prior to fitting the pins)

Whatever you do I hope it works for you.

regards Martin