An engineering / manufacturing question

[Captain Bongo]

I personally wouldn’t use mild steel. I’d use 304 stainless (which is easy to machine) or silver steel.

I did a few for people last year and was going to case harden mild steel but ended up making them out of 304. They all seem quite happy with them.

[CapitalBee]

I did a few for people last year and was going to case harden mild steel but ended up making them out of 304. They all seem quite happy with them.

Thanks Steve.

[robinghewitt]

I thought ordinary free cuttting mild steel included a lead component that made it unhardenable, including case. The moment you had to case harden they gave you the green ended bar that did not cut any where near as sweetly. OTOH my brain is getting old and the less well used memories are starting to fade. I can be safely ignored

[xbow]

I thought ordinary free cuttting mild steel included a lead component that made it unhardenable, including case. The moment you had to case harden they gave you the green ended bar that did not cut any where near as sweetly. OTOH my brain is getting old and the less well used memories are starting to fade. I can be safely ignored

I’m no expert but I think there is more than one grade of mild steel. You’re quite right though, one of them does have added lead.

[Norfolkngood]

I thought ordinary free cuttting mild steel included a lead component that made it unhardenable, including case. The moment you had to case harden they gave you the green ended bar that did not cut any where near as sweetly. OTOH my brain is getting old and the less well used memories are starting to fade. I can be safely ignored

En1a is painted blue and is free cutting leaded steel that dose not weld well.
En1b is painted green and has no lead but welds well.

[harvey_s]

Personally I wouldn't use stainless as it has a propensity to gall in high friction applications.
Most steels EN8 or better should be more than adequate in their natural state and in a pivot you want the pin to wear out before it starts enlarging the hole which is more difficult rectify as you lose the centre and increase the diameter each time.

[keithy]

What you need is silver steel rod from an engineers merchant its available in lengths of about a foot. Its precision ground high carbon steel but drillable you can temper it afterwards if you wish and it will then be very hard. I used to use it in the tool room at work regularly. I would also try the bay.

[NickG]

ditto silver steel harden in oil , then no need to temper afterwards