Insane idea?

[wadebevan]

Hey all,
Getting fall-like around here, which means I need to get back in the shop and start playing with some ideas.

I came across some O1 tool steel scraps from previous blades, or blade attempts.
None of them would make good stock for a full blade, but they should have some use.

Here is the idea that I have been thinking about, and it may or may not be a good one.

Also in the scrap bin is a fair amount of 304 Stainless.


I was thinking of TIG welding a 1/2" piece of O1 onto a SS blank, then shaping, then HT.
The O1 being the blade edge.

Is this just a ridiculous idea?

Often when I am welding carbon steels, I will use 316L SS filler rod as it is said to make a stronger weld.

Over the years, I have TIG welded a lot of SS and have developed some skills in minimizing warping and such.

Any thoughts are appreciated, but please don't send a van with dudes in white coats to pick me up

[Larrin]

Forge welding would be much better

[EOU]

We like it Wade but as you know, we set the bar when it comes to crazy ideas. These are the sort of experiments from which springs new ways of doing things...or more often, quickly forgotten.

[Mark Reich]

Larrin is correct in that forge welding is the only way to construct a laminated blade.

The trick is using a stainless steel that is compatible with a carbon steel. There aren't many stainless/carbon combinations that will readily or reliably weld to each other, to the best of my knowledge.

[wadebevan]

Well, just for giggles, I decided to try the TIG welded blade.
It worked pretty well, even though it is not all that attractive.

The heat treat went very well, and according to the rockwell file test the O1 tools steel edge is at around 63.
The body is 304 stainless.
The filler used was 316L stainless with some very creative heat control in the heat affected zone.

The edge holds really well.
Its initial sharpening result was 156 BESS, and after a weekend of use was 220ish.

It is a single bevel.

I wasn't going for beauty
It is a useful kitchen knife so far, even though the edge does scare me a bit.

[grepper]

I'm not qualified to speak to HT, different steels or knife making in any way, but only going from 156 to 220 after a weekend of use is most excellent. Not sure what a weekend of use means exactly, but I know it's easy to dull an edge that much or much more by just chopping some veggies.

Seems like whatever you did worked well and now you have a useful blade. Cool experiment. Congrats. Thanks for sharing.

[wadebevan]

Thanks Grepper. It has been a fun experiment.

I'd call the weekend use 'moderate' not 'heavy'... however, you got me thinking about knife use and how arbitrary it probably is when relying on the human to recall it.

I am going to measure the edge over time just to see how it behaves.
(I did see one little chip in the edge, it was a true chip not a dent/bend. I'll have to get the USB scope on it.)

Since this thread is called 'Insane Idea', I thought of another one for tracking the use of the knife:
Strap a fitbit on it!

Not sure if I will, but it is a funny idea.

[Mark Reich]

You're riding the edge of insanity (pun intended) with a TIG welded blade. You win if you stick a fitbit on it.

[Mike Brubacher]

All hats off to you Wade! That is a very neat experiment and it seems to be a successful one. I was just thinking about this project a couple of weeks ago and wondering if you had ever attempted it. Seems to me that you have confronted conventional wisdom and emerged victorious. 

You know, if it were somehow possible to clean up and straighten that joining line a bit, it would be a fine looking kitchen weapon!

[wadebevan]

Thanks Mike... I am sure there are master TIG welders out there that could make it a hell of a lot better looking.
My goal was just to get a good mix of the 3 metals involved, and good penetration through the weld.

Stainless likes to warp a lot when welding, so I had to weld about .5 to 1 inch, flip it, .5 to 1 inch, flip it ...

One day I will get into forging and do it proper, but, I had to use what I have to satisfy my curiosity.

It is also my last O1 tool steel blade because it is really quite difficult to heat treat -- if you do it properly.

A good use of some scraps nonetheless.

Now where is that fitbit?