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Good steel for staffs


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Am looking for a source for good steel to make staffs from.  Got some from Esslinger recently and it appears to be crap.  Way too hard and won't anneal (at least I can't do it).  Any suggestions for where I can obtain it.  I'd like a range of sizes from, say, 0.5 mm to 3 mm.  Following link is the stuff I got from Esslinger:

https://www.esslinger.com/staff-and-pivot-watch-and-clock-wire-rod-assortment-blue-steel-55-1-93mm-12-pieces/

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Industrial suppliers such as MSC, McMaster Carr and others sell different grades of drill rod. The most widely used for watch pivots  is water hardening drill rod. This does not mean that water hardening steel is the "best" material, only that it is the most widely used.  The three most commonly used types of drill rod are water hardening, oil hardening and air hardening. Water hardening drill rod is the least expensive and air hardening is the most expensive. As air hardening steel is subjected to the least amount of shock from heat treatment, is has the most dimensional stability. This is why it is used for dimensionally  critical parts such as blanking and piercing (stamping) dies.  Since the making of watches began long before the invention of modern steels, water hardening steel is still used because it was formulated first and established a tradition.

A watch pivot should be made to the correct dimension (@ 1/10 of a millimeter) and reasonably hard (@Rc 50) to resist wear. If it is much harder than that it will transform from spring hardness to wear hardness and be more subject to breakage. 

I went through a lot is experimentation to finally successfully turn something that small in diameter.  I would turn the pivot down to about .010 inches and then watch it snap off when I tried to machine to a smaller diameter. The goal was about .004 inches in diameter. I think most people would turn it down to .010 thousandths and then grind it down the rest of the way in a Jacot tool. Instead of taking that route I set my watch lathe up with high precision dial indicators and fed the cross slide in using very small increments. I also used a carbide cutting tool.

david 

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The above mentioned assortment is probably that from India. The kind of steel is absolutely unknown, the Indian exporter does not give any details. Such an item I would buy from a source only that will give technical data, too.

Frank

 

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