Steel Grade Question

[frdtrkguy]

Help please

Im gonna make some custom output shafts so the steel has to be drillable but strong to resist torque. Mcmaster carr has the following options:







General Purpose
Water-Hardened W1 Tool Steel


Because W1 is not heavily alloyed, it is one of the easiest tool steels to machine. Its high carbon content makes it suitable for many applications even without heat treating.




Multipurpose Oil-Hardened O1 Tool Steel


One of the original tool steels, O1 has a good combination of machinability and resistance to wear and abrasion.




Multipurpose Air-Hardened A2 Tool Steel


A very fine grain structure results in a superior-quality steel.





Wear-Resistant Air-Hardened D2 Tool Steel


If you're looking for a versatile high-carbon/high-chromium tool steel that has great wear and abrasion resistance, D2 is the choice for you.




Very Hard M2/M7 High-Speed Tool Steel


A high molybdenum content increases this material's hardness, which means it will resist softening and maintain sharp cutting edges even at elevated temperatures.




Ultra-Hard M42 High-Speed Tool Steel


This material is often called cobalt steel. It also contains molybdenum, making it suitable for working the hardest metals.

[Charlie-III]

I would stick to one of the 1st 3 listed, keep in mind how you are going to heat treat it. Some are easy, some need a long heat soak.

The later materials are very hard, thus not as good in shock loads.

I'm sure the real machinists will give better answers.

[trwelds]

Im not sure what kind of force or loads these pieces would be under, would have to do some searching into that and what the steel you listed is good for.

What you can maybe do is take a OEM output shaft and do a hardness test on it and then go from there. that should give you enough data to know what to choose if you want to go higher or lower. generally the harder tool steels crack with little bending applied but i just don't Think the output shafts would be even close to these kinds of forces.

[binaryterror]

Outputs need to be chrome moly 300M or 4130 or 4140 material.

Harden it after machining.

[JeepinDoug]

Oil quench is great to work with.
When you're done with the part, heat to cherry red then quench in oil.
Keep moving the part until it's cold.
That's full hard.
Polish it clean, then heat it again until a light purple.
This will draw the temper down to around the hardness of a band saw edge, rugged without being brittle.

[frdtrkguy]

Thanks for the input thus far!!

[frdtrkguy]

Ok, so, I found some old 5mm axle shafts from a Wheely King I think that Im gonna use. After I finish cutting, drilling and grinding em how I want, do they need to be re-heat treated? And if so whats the procedure?

Thanks!!