Hi folks, I'm heating a #4 Morse taper lathe center as I type this. As a machine operator my understanding of the hot side of metal working is very limited. So if any one would like to comment on what I'm doing here i would be glad to read what you have to say.
I started with a #4 dead center that had been abused to the point that, well there was no point the 60* taper was blunt to about 5/16" so I turned a new point on it and could tell that it was way harder near the O.D. than near the center. I don't know what it is made of but it is not rusty after many years of laying around (other parts that were stored with it are). It was pretty hard, I had to run the spindle between 40 and 60 RPM to cut it with Carmet 717 grade inserts. slowing down as I approached the O.D.
I have no forge yet so the part was heated with a rose bud till it was glowing red from the tip about 2/3 the way back to the O.D. it was then quenched in hydraulic oil and is now in the oven set at 400* going to soak it for 2 hrs. and let air cool. I hope I end up with a wear resistant but not brittle 60* taper. Thanks for any advise or comments, oscer.

Yeah, dead centers have a hard life, especially from newbies cranking them as tight as they can to try making up for not doing a proper set up. <sigh>

Anyway, The only thing I would've done differently is use a magnet to determine if it'd reached critical temperature before quenching. Did you try a file on it before starting to temper? As quenched a sharp single cut file should skate.

Worst case, you haven't hurt it and may need to anneal and re-heat treat it. Dead centers don't need much flex so a little brittle isn't a killer but if the point does chip don't burn up your inserts, grind it. I chuck them up and use a fine stone on my dremel, they come out near perfect, smooth and shiny for minimum friction in use.

I think you're okay though, if anything a little soft but if not okay, you DO get a redo. <grin>

Frosty The Lucky.

Thanks Frosty, I did check it with a magnet before quench,it had no effect. Wish I would have checked with a file after quench. When checked with a file after tempering it can dig in a little and it seems to be the same from point to O.D. this center will only be used as a live center in the head stock so I'd rather be a little soft than have a brittle nose.