Making gouges - has anyone tried stainless steel turning tools?

If you're doing it simply because you can then great, but I should think that the carbon steel would hold a better edge. Problem is, your friend is going to ruin them pretty quickly when he tries to sharpen them. Upon ruining them he'll never get a clean cut and may perhaps become disillusioned with this hobby. Buy him a cheap set of HSS tools from HF or someplace like that if you want to be nice to the guy, and try making your own carbon and stainless tools for yourself. Sounds like fun, and a nice use of scrap material.

J.

Prometheus wrote:

I think it is a nice thought to provide the fellow with tools to use with his lathe that you are selling him; however, the materials that you have available are not really suitable for making turning tools. Aluminum and cold rolled steel are totally unsatisfactory as turning tools. I do not believe that stainless steel would make a very good turning tool either. I have seen some stainless steel kitchen knives that were fair, but they never did sharpen extremely well. I would recommend that you suggest that he buy the high speed steel set of turning tools from Harbor Freight to go with his new lathe.

Fred Holder

Prometheus wrote:

Hmmm... Well, I do have a small set of cheap ones that are carbon steel I could let go with the lathe as well. They make nice clean cuts, but they're thin and a little flimsy. If stainless kitchen knives won't take a good edge, it's probably not worth messing with for turning tools. I've had stainless knives in the past, but they were the serrated Ginsu style, which (of course) I never tried to sharpen. I'll probably just try making a scraper for myself to test the material out, and see how that goes.

Any thoughts on the carbon steel if it is tempered? The guy I'm selling the lathe to works with me, and would actually be the one pressing the gouges after I laser cut them if we do this, so I'm sure he's competant to heat and quench them a few times. I'll pass along the HF idea, too- I just know I had a bit of sticker shock when it came time to buy lathe accesories when I started, considering I had just spent all my money buying the lathe itself.

Most grades of stainless are too soft for tools. Unless you have a hard grade, they will not hold an edge. The same is true for low carbon steels. You could heat treat the steel to harden it, but that is just a case hardening. The first time you grind, you remove the hard case and you are back into the softer steel. Brad

I found this on the metalworking group some time ago. It's called Superquench. I'm no metallurgist, but perhaps it would/could be helpful in this situation. Or perhaps I'm typing out my ass.

This mixture is reported to harden mild steel and will harden hypereutectoid alloys to the point where they become dangerously brittle.

It is the user's responsibility to provide due care when employing this mixture.

Superquench:

1. 5 lbs salt
2. 28 oz Dawn blue dishwashing detergent
3. 8 oz Jet Dry or other rinsing aid
4. Water to complete 5 gallons of the mixture

This is reported to "age" in the bucket athough some smiths report being able to sustain the mix by using a tight cover.

So there.

-Phil Crow

I did a little research on this, the only problem is that what I've got to work with no longer has a material code on it- we've just got it marked according to gauge and finish in the bin. But I will try the method you've suggested, that's a good one. My guess is it's 304, though that's bound to change depending the job the scrap was used for. Looks like a quick test with a magnet will tell me if I'm right about that one- if not, it'll be the tempering test. What I know off hand is that when it is cut with the laser, it does not have a carbon edge like steel does, and it very difficult to file or grind. It is very ductable, and is weldable. I can't for the life of me remember if it is responsive to magnets or not. I know the burrs are sharp enough to cut fingers like a scalpel if they come off the shear with an edge on them (thankfully, not too common an occurance.)

I'll be making the test ones not only because it's fun, (which it likely will be) but easy as well. Shouldn't take more than one lunch break to get them all cut and the gouges broke, then it's just a matter of grinding the cutting edges- something we all have to do anyway. The one I'm particularly interested in for myself is a captured ring tool or two- I'm not too keen on buying one for such a limited application, but making one might be awfully fun.

That super quench is another form of case hardening. Great until you need to sharpen and grind thru the case. Also 304 is too soft for cutting tools. You will continually need to resharpen. Brad

You are right- I tried a bit of scrap, ground and sharpened it to a razor edge, and it cut beautifully- for about 2 minutes. After that, it was about as good as a butterknife.

But it's interesting to note that the 304 is highly recommended for metal spinning. Definately something for me to play with- just not in the way I initially thought.

Quenching in brine is more severe than quenching in plain water, which is more severe than quenching in oil. It will harden a low carbon steel somewhat, but to nowhere near the hardness you want for a cutting tool. For that, you need more carbon. You can add carbon to the surface of low carbon steel through casehardening, but that involves adding the carbon to hot steel - not during the quench.

John Martin

Right on John, nobody can make hard cutting metal by super quick cooling lead or other........ Have fun and take care leo Van Der Loo

John wrote: