Question Re: o2 drill rod mod to PM tool rest

[Greg Ketell]

So I bought some 1/8" O2 (oops I meant o1, not o2) oil-hardened drill rod to put on the top edge of my PM and Jet tool-rests to prevent my tools from gouging the tool-rests. Do I harden it first? Or is it good enough the way it is?

Thanks in advance

[Jerry Marcantel]

Greg, I bought some 5/8 and 3/4 O2 rod from MMC, and made a bunch of rests for myself. I didn't heat treat them because when I was parting them to size, my parting tool just screeched and made a shiny groove . I took them off the late and cut them with a saw, then used carbide to dress up the ends.
I have found that the rod is not as hard as I thought it should be because I'm starting to find tiny divits on the surface. The aren't as bad as what you get on a cast iron rest, but still a little aggrevating...... One of these days, I'm going to cook them to the proper temp, when I find out what it is, and heat treat them myself........... Jerry (in Tucson)

[Greg Ketell]

Hi Jerry,

I was searching on the right way to harden it too. Here is some stuff I found:


Heat Treatment: Sections smaller than 1/4" heat to 1450 - 1475 F and hold until heated through. For larger sections, preheat to 1200 F, then raised to 1450 - 1500 F to hardening temperature, hold one-half hour per inch of cross section. Quench in oil at 125 - 150 F and temper immediately.

For O-1 hardening temperature is 1500. Use a magnet on a piece of wire. When it no longer sticks to the punch while heating the punch then you have got it hot enough. Do this test over your container of quenching oil and simply drop it in.
Temper in the oven at 400.

You need to heat to about 1500 deg.F (bright red), quench in oil and then draw it back by putting it in a 400 deg.F oven (kitchen oven is fine) for about an hour to get Rc~ 58/60 which should be good

"If you don't already have some get some Brownells Non-Scaling Compound. Wonderful, wonderful stuff. Your punch will come out of the quench looking a beautiful grey color, and you can then temper by color."
One additional advantage to the Brownell's anti scale is that it prevents decarb of the surface of the O-1. That is significant benefit as well. Gotta love O-1. Great stuff.


I'm thinking that I'm glad I have a kiln for when I need to harden my thicker pieces. Trying to hold a constant temp on a 16" piece of 5/8" rod for 40 minutes will be a trick!




Greg, I bought some 5/8 and 3/4 O2 rod from MMC, and made a bunch of rests for myself. I didn't heat treat them because when I was parting them to size, my parting tool just screeched and made a shiny groove . I took them off the late and cut them with a saw, then used carbide to dress up the ends.
I have found that the rod is not as hard as I thought it should be because I'm starting to find tiny divits on the surface. The aren't as bad as what you get on a cast iron rest, but still a little aggrevating...... One of these days, I'm going to cook them to the proper temp, when I find out what it is, and heat treat them myself........... Jerry (in Tucson)

[Richard Jones]

I bought some annealed 01 rod and epoxied it to my rests. Better than the cast/ductile iron, but not as hard as, say, my Robust rests. I was surprised at how "soft" the chart says it is, as a file or hacksaw woudn't touch it. I had to take the corner of a grinding wheel and then snap it off.

Maybe cut a bunch to the lengths you need and take it out somewhere for heat treating?

[Thom Sturgill]

I bought some A2 for tri-corner tools. Heat treatment is similar to O1 except no quench, just let it cool in air. Use the magnet test to tell when you have it hot enough to harden. As to the oven, I was told to hold it at 400 for about an hour and then let it stay in the oven while the oven cools. Best would be to leave it over night without opening the oven door.

[Dave Ogren]

If you are going to use a torch, hang the part horizontally and heat to a dull red then quench in oil. Later to temper or draw back so that it is not brittle use a torch and just heat it up not to any color, maybe a light grey, just burn off the oil then air cool. Did this for about 40 ++ years with out a problem. Good luck.

[Harry Robinette]

I'm with you Dave O. my dad did the same thing for many years. When I did the rest on my Vega I just used a piece of hard rod I got mine from a place here in Akron. It's a scrap iron place and they just called it Hard Rod have to cut it with a Cut-off tool and thin cutting plate. It's been there about 7 years and no marks or dings.
Something to remember is to grind the edges off all your flat tools so they don't cut the rest.

[Greg Ketell]

I learned something last night. You can't (well, I couldn't) get 6 inches of 1/8" drill rod evenly hot with a blow torch. It lost its heat too fast such that by the time I had moved the torch to "inch 3", "inch 1" was no longer red hot. Didn't matter how fast or slow I moved the torch, I just couldn't get it all hot at the same time.

And, even the very tips of needle nose pliers were enough of a heat sink that it prevented me from getting that first 1/2 inch hot at all.

Gk

[Thom Sturgill]

Greg, what kind of torch are you using? Propane will not produce enough heat, Mapp gas is marginal. I used acetylene. Not oxy-acetylene though that would work it can produce too much heat, I have a torch I got for silver work. This may be another reason to use A1 steel instead of O1 or O2

[Greg Ketell]

Greg, what kind of torch are you using? Propane will not produce enough heat, Mapp gas is marginal. I used acetylene. Not oxy-acetylene though that would work it can produce too much heat, I have a torch I got for silver work. This may be another reason to use A1 steel instead of O1 or O2

I have a mapp gas torch. A1 would definitely be easier since you could just heat it up from one end to the other and it would harden up behind the flame. O1 the entire thing has to be glowing red at the same time before it gets dropped into the oil.

Learning a lot as I do this for the first time. Next order will be A1 for sure.

[Jerry Marcantel]

Greg, I cooked some O2 in a BBQ once. The whole 12" piece was red when I pulled it out. I used mesquite, and from what I heard a long time ago, mesquite will get to 1400°. That might be an alternative, and if you want it hotter, blow some air into the coals. ?????? ............ Jerry (in Tucson)