Hot rolled vs cold rolled

[stephenc]

I have a couple small parts to make that I want to case harden with casenit .
Is there any reason to pick hot or cold rolled 1018 over the other or will they both be about equal when done .

I do understand that the cold rolled is more likely to have internal stress and be more likely to warp but the part taking the case hardening is more important then dimensional stability.

Thanks

[Rich_Carlstedt]

No difference really other than the warp potential.
Hot roll is generally 1020 and that means a slightly higher carbon content but as you know , machining is not as good

Rich

[stephenc]

thank you . i do prefer to use cold rolled because it is a little easier to work with .
plus in this case it means i can use some stock i have on hand and not have to make a trip to town to scrounge some material up .

[Harold_V]

One disadvantage of using hot rolled material is size. If you're gripping with a chuck, no problem, but hot rolled is generally oversized, and not round, so it doesn't lend itself well to working with collets. I've used the Jacobs collet chucks for the material, which seems to be satisfactory, however. Wish I had one for my Graziano.

Harold

[liveaboard]

I've been machining some hot rolled 1" rod today; what a pain compared to the nice cold drawn rod I was using before.
I can only get hot rolled here in southern Portugal.

It's so lumpy and irregular, time is wasted.
Cheap though.