Steel Selection

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I need some information on what type of steel to use for machining some parts. Basically what I am going to have machined will look like a miniature barbell. It will have 1" balls on the ends with a 4 1/2" long 3/8" diameter shaft connecting them. I would like to have them made from something that is a little tougher than mild steel for wear and weather resistance, but also be able to weld and drill it if the need arises. This is my way of getting around have to weld or drill ball bearings as mentioned in a previous post. Any information regarding the type/name of steels fitting this category would be greatly appreciated............thanks.
Reply:A few questions:1) what do you mean by "mild steel"?2) what are they used for (ie why the need for wear resistance)3) how critical is the weldability?For example, a 1018 would offer superior wear resistance over a 12L14, but a 1045 would be better yet.  None of these offers any real corrosion resistance.  A 300 series stainless offers great corrosion resistance, but won't wear worth a hoot.  A 400 series stainless will wear much better, but offers less corrosion resistance at a higher cost.  Perhaps a tool-steel like an O-1 gage stock would suit your needs better, offering a light corrosion resistance (once hardened).The best solution may be to describe your needs to your local steel vendor, and select from what he has in stock.  Buying non-stock material is small quantities can get costly VERY quickly.
Reply:Aaron,Mild steel to me is like the hot rolled plate that will be clamped to both sides of the ball creating a pivot point. I want something that wears better than standard hot roll so the plate will wear and not the balls. The parts (balls) will be clamped between 2 pieces of hot rolled plate with holes drilled and counter sunk where the balls will be seated. A bolt will be used to apply clamping force allowing the arm to be loosened for positioning, then tightened when the arm has been placed it the proper position holding the part to be welded. Weldability is important because it will allow me to adapt these machined joints to other uses. For example if I only need a ball at one end I could cut one of them off then weld the remaining shaft and ball to whatever. I hope this answers your questions. To me the standard angle iron and flat stock purchased at a steel supply place is what I consider mild steel...........thanks
Reply:Well, the standard plate/angle at the supplyhouse is likely a "mild steel", but that's like saying an apple is a fruit.  There are many types of "mild steel".  HRS or CRS are merely methods of manufacture, if you will (yes, it is mch more complicated.   I just am trying to simplify here).  One method, HRS, produces inconsistent dimensions & mill scale (crap on the surface of the metal), but is easy to machine and bend.  The other, CRS, produces steel that is much more dimensionally consistent, generally "clean", and is tougher (rough generalization)  than HRS.I would consider a 1045 steel (a CRS).  It is relatively strong, easier to machine than a SS, and can be hardened if needed.  To get corrosion resistance, have it plated.  An electroplater will likely charge a minimum fee, but they are not too bad.
Reply:Thanks Aaron,1045 it will be.
Reply:Let me know how it works.  I hope I have clearly understood your intentions, and I haven't misled you.  There is an art to material selection, an art to which I am struggle to achieve myself.  There are so many types of material available, and the selection will vary from supplier to supplier based on industrial needs in the region.  If your supplier doesn't stock 1045, (I can't believe he wouldn't) just ask what he would recommend.