Question regarding hardening of 01 steel

[Brian Rupnow]

On the engine I am currently building, I have a situation where a mild steel gear is bolted to an 01 material hub. I want to harden the end of the hub which has a cam machined on it, but see no real necessity for hardening the flanged end of the hub. I haven't done this before, and I'm wondering, in fact, can it be done. I have flame hardened and quenched many cams and tappets to harden them, but with them I wanted the entire thing to be hardened, so it was never a problem. So, I'm wondering--can I heat just one end (the cam end) of the hub to cherry red and then quench the entire part, or do I have to heat and quench the entire hub. ---Brian

 

[Jasonb]

Just get the lobe up to heat and then quench but only dip the lobe into the oil so any heat in the rest of the part cools down slowly. It's no different to hardening say a punch or chisel where you want the business end hard but the bit you hit soft.

 

[Brian Rupnow]

Thank you Jason.---Will do that.---Brian

 

[clockworkcheval]

I'm wondering whether you should heat up the whole end where the lobe sits and then quench in oil with the axis perpendicular to the oil surface. I've learned that in general you quench shafts and tubes by putting them vertical (and fast) in the oil to avoid distortion. But maybe it doesn't matter with a very local heating of just the lobe. I would appreciate your report on the results.

 

[werowance]

you can also dig up some yard clay and make a putty out of it and dab around the part you dont want to harden. but if the part is short the heat will still travel and when quinched will still harden partially. also watch for warpage

 

[Brian Rupnow]

Thank you for your answers fellows. I was able to heat up the cam to cherry red while it was still bolted to the camshaft gear and flip the entire gear into a can of old motor oil. The cam area hardened up very nicely, and there was no measurable distortion.---Brian.

 

[clockworkcheval]

Well done! Thanks for sharing the results.

 

[SmithDoor]

On the engine I am currently building, I have a situation where a mild steel gear is bolted to an 01 material hub. I want to harden the end of the hub which has a cam machined on it, but see no real necessity for hardening the flanged end of the hub. I haven't done this before, and I'm wondering, in fact, can it be done. I have flame hardened and quenched many cams and tappets to harden them, but with them I wanted the entire thing to be hardened, so it was never a problem. So, I'm wondering--can I heat just one end (the cam end) of the hub to cherry red and then quench the entire part, or do I have to heat and quench the entire hub. ---Brian

I used a lot O1 for all type of parts.
Some I did not heat treat.
Whenever I need to heat treat, I just heated to orange . Then put a toaster oven around 350°F or 450°F for a hour or two.

Dave