question for knife makers or metal workers ??

[mr dazzler]

I have acummulated a few TCT saw blades over the past few years, and was thinking about making some blades from them. What I dont know, and wanted to ask of an expert, is what is the steel like. I know the teeth do the cutting, is the rest of the disc just a bit of old mild that wont harden and temper to make a good blade (I want to do bent knife blades)?
Thanks in advance

 

[Everything Mac]

I believe it depends on the blade. Best thing to do is cut a bit off and heat treat it - see if it will harden in oil, if not try water. If it does it'll make a blade if not then it won't.

All the best
Andy

 

[Dave Budd]

Yep, just as andy said. Thats pretty mucb what you have to do any time you recycle old steel

I would suggest just buying some virgin steel if a known grade. It will be mucn easier and doesn't cost much

 

[mr dazzler]

Thanks for the advice! I'll try it any way, if it turns out duff, nothing to lose. One of the blades is an old fashioned one with no TCT teeth I think I'll start with that one. If nothing else it would be good cutting out practice. One of the blades is around 3mm thick, might even make a tiny elbow adze blade
Thanks again

 

[Fadcode]

Quite possible the steel away from the teeth is not hardened , but tempered to allow a bit of flex when cutting, try a file on it to see if it is hard, if the file skates across it, its hardened if it cuts in it isnt, then cut a piece off harden it and try the file again.
It is one of the problems when you dont know the characteristics of the steel, you can waste a lot of time and effort and end up with the same piece of scrap, always best to deal with steel you know is suitable.

 

[Everything Mac]

You can file it after heat treatment but I was thinking just stick it in a vice and whack it (Wearing proper PPE) - if it bends it's duff if it breaks you're on to a winner.

Andy

 

[Ascobis]

Whatever you end up doing with your TCT blades, save a couple of the carbide teeth. I have a challenge for you: fabricate a knife sharpener just like the ones for sale everywhere but with an included angle sharper than the useless 40 degrees of the retail versions. (I want to make such a sharpener, but don't have any TCT blades.)

 

[Robson Valley]

Sort of like this one from Lee Valley? I bought several, the included bevel angle is about 20 degrees and works OK in the kitchen.

http://www.leevalley.com/en/wood/page.aspx?p=60002&cat=1,51222

 

[Ascobis]

"To be effective, a cutting tool not only has to have an edge of zero width, but the angle at which the two surfaces meet must accommodate the intended use of the tool and the material from which the tool is made." -- Leonard Lee

Those using unknown steels as described up-thread will have to find the best angle by experiment. An adjustable angle, perhaps involving set screws, will let a TCT-steel knife maker tune a sharpener to the new blade. Gadget or not, the maker will still have to find the best geometry.

[As would be expected, that LV model is closer to the ideal than most.]

 

[Robson Valley]

Porsche kitchen knives are fairly expensive. He (brother of the car-guy) recommends 20 degrees total included bevel.
Also recommended is a 4k Polar waterstone. For those proficient in freehand sharpening, it all comes together.
Sharpened and honed, that's good enough for ripe tomatoes. My bone cleaver is as crude as it needs to be and 40 degrees.

I'd recommend a carbon steel Asian cleaver as a steel source.

 

[Janne]

With dubious steels we need a larger angle ( more degrees) than with refined steels.

I am a custodian of some knives ( food prep, meat prep and wood carvers) from early 1800’ I found on grandmothers farm in Sydetenland ( today Czech Rep)
Made by local blacksmith I assume. Angle of around 30 degrees or do.
Only thickness and size differ between them.
Design is the same you will find in museums around Europe. Proto Mora shape.

All marked by my ancestors initials. He passed away in mid 1800’.

 

[petrochemicals]

Chances are that the steel used to weld the tungsten carb in is low carbon <0.5, other wise the welds harden, so basically no good for knives. The one that has been hardened itself is obviously reasonable at edges.

 

[Janne]

If you make the knife of that (substandard) steel, you have just recreated a blade as it would have been before the modern metallurgy.

Most Viking swords and bladed implements were highly effective, yet made out of rubbish materials!

You need to learn the limits of the tool, and adopt your usage.

 

[petrochemicals]

Janne, folding carbon bearing stuff into it should create the woltz steel, leaves etc. Carbon nano tubes are formed apparently.

 

[Janne]

Yes, but quality steels like that were incredibly rare and expensive.
The average man and woman had only tools from very crude, simple steels.
And worked well with them.

Of the tens of thousands of Norse iron/steel implements found, only a few (less than 200 found) luxury swords were made from quality steel, steel made (possibly) by Franks in Germany.
The Ulfberht swords.
No knives or other bladed implements were of this steel.
The thoughts are the crude steel implements were made locally, either from local (bog iron)
material or traded or conquered stuff, reshaped locally.
Of course, the steel was still superior to the Roman or post Roman steels.
A knife made from lesser quality steel can still be useful and fully functional, so the effort the OP intends to put into it is not wasted.
Just carry a small sharpener.

He never mentioned he wanted to do any blacksmithing, just cutting and shaping existing steel?

Wootz - we still do not know how they made it. What is called Woitz today displays different metallurgy than the real Wootz. Many have claimed to have replicated it though.

 

[Ascobis]

Of course, the steel was still superior to the Roman or post Roman steels.
.

Thanks for the information. First, because I believed Roman metallurgy stopped at bronze. Second, finding something new to learn is always a pleasure.

[trying to stay on bushcraft] Mild steel would be adequate for food cutting edges. I imagine that bodkin arrowheads would work ok. Hammer-sharpened scythe blades want to be soft.

 

[Janne]

No, the Romans had a huge Iron and Steel industry.
There are sites all around UK where they smelted. Many in Sussex and Kent.

The Bronze age went over to Iron Age around 1000 BC in Europe. So half a Millenia before the Romans started being Romans

Mild steel is not ‘bad news’ imo.

It brings another level to bushcrafting. So a good, educational thing!

The Same, a culture where knives are hugely important every day, used mild steel blades well into the 1970.
Like an old Same friend told me, the blades were made from cask bands, were soft, had to be sharpened every hour during use, but did not break!

 

[Ascobis]

Sort of like this one from Lee Valley? I bought several, the included bevel angle is about 20 degrees and works OK in the kitchen.

http://www.leevalley.com/en/wood/page.aspx?p=60002&cat=1,51222

No joy. I wrote Lee Valley customer service. The included angle is 38 degrees.
The product itself, with the ability to change cutting edges, is cool. Alas, it's just not tight enough for knife snobs with waterstones.

 

[Robson Valley]

What the Hello good is 38* in a kitchen? Are we whacking a side of bison? My Chestnuts don't look that fat at all.
Whatever LV told you, the basic bevel is really good for repairing cheap knives to get back to a workable bevel edge.

I look at the steel curlies spalling off into my sink and smile. A few soft licks on a Henkel rod works well enough.
I'm always going for 20* in the kitchen.

I have really good water stones (gifts) but never drag them out. To be honest, I get better results with the cheap
Asian cleavers that I buy for $7.00 in the far back ends of Asian grocery stores.

 

[mr dazzler]

I didnt want anyone to think I was being rude and ignoring the thread I started, I just imagined it had naturally run its course and "wound down" and was surprised to see more comments in the last few days....
I should have said, my idea is to cut out the shapes for some bent knives, and put a bevel to them, then bend them to the curve I know I want with pliers around a simple mandrel form, then harden and temper. I havent got the facility to do any forging at present

As for the suggestion about a TCT knife sharpener, I think the small teeth would be a bit fine and fiddley to customise. BUT what about using 2 cheap TCT router cutters (straight sided) You can get them an inch or more long, or 1/2 inch router bits 3 inches long. The 1/4 inch shanks could be handy to fit into some sort of adjustable mechanism? I dont mean revved up to 22,000 rpm either just manually pull the knife blade between the 2 cutters

It amazes me that native carvers used beaver teeth to carve bowls and other forms, and that they gladly used the iron bands off of ships barrels as a substitute source for blade material. Ahhh-but...were they HIGH CARBON iron bands???? LOL Do what you can with what you have...
But then cedar is soft to work with. I dont know if norse carvers worked the wood wet ot seasoned. I know the boat builders did