Good, Easy to machine Steel (not 12L14)?

[Builder4wd]

Hi guys,

I'm unfamiliar with all the different types of steel. I'm looking for a durable, easy to machine steel that does not warp. I know 12L14 is easy to machine, but I don't want to use it because it contains lead. Any suggestions?

Thanks!

[dertsap]

depending on what you need it for leaded steel is harmless , 10-18 is pretty common

[widgitmaster]

1018 is cold rolled steel, contains stress from the rolling mill.
Hot Roll steel is a little more stable, and soft for easy machining.
However, O1 Tool Steel is a lot stronger for automotive use even when un-heat treated!
Tool steels come in many grades, and every size!
12L14 is soft, east to machine, and the lead gives it an almost stainless characteristic.

You need to be more specific as to the application, as there are so many variables and alloys!

Eric

[Builder4wd]

Thanks for the responses. For application, I was looking into making a basic spindle body and shaft. Another application would be for small mechanical rotary parts, such as for r/c cars. I may be able to access a full size lathe, but for the most part I'm planning on doing this with a benchtop machine, hence the desire for relatively easy to machine material.

Thanks

[handlewanker]

Hi, I've been using s12l14 in my capstan lathe for a long while. The reason why it's used here is to stop the long curly swarf that tangles round the tools and makes it a pain to get rid of.
The chips break up short and also cut easily and leave a very smooth finish, but here's where it ends. The material is too soft for most stressed parts. Try bending a piece of bright cold rolled mild steel and it will develop cracks and break.
The s12l14, which is a leaded steel, is so malleable it will bend easy, and also does not have much surface strength. Good for small parts and easily machined but the strength is sacrificed for ease of machining. If you don't believe me, test it for yourself.
I recently had to make a batch of "U" bolts out of 12mm diam leaded steel, about 60mm across, using a fly press and they bent up in one press with a rudimentary die. I ran out of material and used a bit of 12mm bright mild for the last 6, and had one hell of a job to stop them springing back. Also the cracks on the outside of the bend scrapped them. It's crap material at best and only used for mass production.
Ian.

[HuFlungDung]

"Stressproof" or C1144 grade is also quite nice to machine. It is sulferized for machinability.

Type 303 stainless is also quite nice.

I do not think that any of the modified steels that have their composition adjusted for high machinability are recommended for welded construction.

[Geof]

Originally Posted by HuFlungDung ....I do not think that any of the modified steels that have their composition adjusted for high machinability are recommended for welded construction.

I have seen this stated in other threads/posts but I have never had problems welding leaded steel so I looked for some information. This is from; www.key-to-steel.com

I put in the Bold Italic.

Free Machining Steels
The term free machining can apply to many metals but it is normally associated with steel and brass. Free machining is the property that makes machining easy because small cutting chips are formed. This characteristic is given to steel by sulfur and in some cases by lead. It is given to brass by lead.

Sulfur and lead are not considered alloying elements. In general, they are considered impurities in the steel. The specifications for steel show a maximum amount of sulfur as 0.040% with the actual sulfur content running lower, in the neighborhood of 0.030%. Lead is usually not mentioned in steel specifications since it is not expected and is considered a "tramp" element. Lead is sometimes purposely added to steel to give it free-machining properties.

Free-machining steels are usually specified for parts that require a considerable amount of machine tool work. The addition of the sulfur makes the steel easier to turn, drill, mill, etc., even though the hardness is the same as a steel of the same composition without the sulfur.

The sulfur content of free-machining steels will range from 0.07-0.12% as high as 0.24-0.33%. The amount of sulfur is specified in the AISI or other specifications for carbon steels. Sulfur is not added to any of the alloy steels. Leaded grades comparable to 12L14 and 11L18 are available.

Unless the correct welding procedure is used, the weld deposits on free-machining steel will always be porous and will not provide properties normally expected of a steel of the analysis but without the sulfur or lead.

The basis for establishing a welding procedure for free-machining steels is the same as that required for carbon steels of the same analysis. These steels usually run from 0.010% carbon to as high as 1.0% carbon. They may also contain manganese ranging from 0.30% to as high as 1.65%. Therefore, the procedure is based on these elements. If the steels are free-machining and contain a high percentage of sulfur the only change in procedure is to change to a low-hydrogen type weld deposit.

In the case of shielded metal arc welding this means the use of low-hydrogen type electrode of the E-XX15, E-XX16, or the E-XXX8 classification. In the case of gas metal arc welding or flux-cored arc welding the same type of filler metal is specified as is normally used since these are no-hydrogen welding processes.

Submerged arc welding would not normally be used on free-machining steels. Gas tungsten arc welding is not normally used since free-machining steels are used in thicker sections which are not usually welded with the GTAW process.

[ctate2000]

You might try 4140 4150 8620 1144. Buying hot rolled material will help prevent warping.