Photos Straightening Hammer (JT's design)

[HSC ///]

I was also looking at different chisels for this lately. Could you show us the tip/point of yours?

I rounded the edge with a diamond film to break the corner

 

[Scaniaman]

I rounded the edge with a diamond film to break the corner

Thanks, very helpful of you!
So, a flat chisel with rounded edges.
I was also looking at a pointed one, thinking of rounding of the tip and try that. This one is 20 mm at the shaft.

 

[HSC ///]

Thanks, very helpful of you!
So, a flat chisel with rounded edges.
I was also looking at a pointed one, thinking of rounding of the tip and try that. This one is 20 mm at the shaft.

That one looks to pointy for my preference
But In general I don’t think the shape matters too much. It’s the hardness and impact resistance and they all leave marks in the steel you have to grind out.

 

[Willie71]

Yes. It has to be harder than the steel
The chisel I’m using is in the 70’s as I recall

I don’t think u can get steel that high of hardness

You would have to use z-max, or Rex 121.

 

[Joker66]

Has anyone noticed that using this technique causes weakening or cracking in blades?

 

[HSC ///]

Has anyone noticed that using this technique causes weakening or cracking in blades?

No. Never cracked a blade this way
See Murray Carters video on straightening.

 

[Scaniaman]

Yes that is a good video.
Just ordered a flat head wolfram carbide chisel (made for hand carving stone) with 10 mm wide head, 170 mm OAL, from a reputable German brand (I'm in Europe). I will also round off the corners. Interested to give this a go.

 

[PEU]

I've been using a chipping/welding hammer with the tips slightly flattened for this for at least two years, today while using it it chipped and the chip went straight to my left hand, had to sanitize and stop the minor bleeding...
Tomorrow will grind a groove where the flats are and silver weld some carbide rods...
This method works very well for my thin culinary knives.

Pablo

 

[JTknives]

Out of the tons of blades I have straightened only one has cracked and that was a .0395 ulu made out of aebl. It was warped so bad that the amount of peening it needed exceeded what the tip could take.

As to using HSS I never got good life out of them. I switched to carbide and never looked back. I now use a sewing machine that I modified into a blade peening machine. With the volume of blades I process I could not keep up doing it by hand.

 

[N.W. Gean]

Out of the tons of blades I have straightened only one has cracked and that was a .0395 ulu made out of aebl. It was warped so bad that the amount of peening it needed exceeded what the tip could take.

As to using HSS I never got good life out of them. I switched to carbide and never looked back. I now use a sewing machine that I modified into a blade peening machine. With the volume of blades I process I could not keep up doing it by hand.

I've noticed after some use that the tap point is dull. Will any type of carbide work? I can get a tungsten carbide rod blank pretty cheap.

 

[Scaniaman]

I was looking around at tungsten carbide blanks and noticed many had specs at 55 Hrc. A little surpised, but I don't know anything on the subject.

 

[JTknives]

Tungsten carbide is the only thing I use for my straightening hammers. 55rc really soft, but there are different grades of TC. It’s not the tungstion carbide that hard or soft it’s the binder that holds it all together. In the past I made all my straightening points out of busted off 1/8” carbide burrs.

 

[R.C.Reichert]

Does this straightening method work on thicker blades like bowie knives, or is it just for thinner stock?

 

[JTknives]

I have straightened blades over 1/4”. blade thickness does not affect the process.

 

[Dan512]

Yes that is a good video.
Just ordered a flat head wolfram carbide chisel (made for hand carving stone) with 10 mm wide head, 170 mm OAL, from a reputable German brand (I'm in Europe). I will also round off the corners. Interested to give this a go.

I am in Europe too and struggle to find a carbide ball or chisel to build a staightening hammer.

Could you tell me what you ordered and where?

Thanks

Dan

 

[PEU]

just use a broken carbide endmill or drill bit, shape it with a diamond wheel and then weld it to a grooved hammer.

Pablo

 

[Scaniaman]

I am in Europe too and struggle to find a carbide ball or chisel to build a staightening hammer.

Could you tell me what you ordered and where?

Thanks

Dan

This is the brand I used for the chisel tipped hammer:

BAVARIA Bildhauer-Werkzeuge Druckluft-Werkzeuge

BAVARIASteinmetzwerkzeuge der Firma BAVARIA haben eine lange Tradition: 1872 als Geier Werkzeuge in Königsbrunn bei Augsburg gegründet, produziert BAVARIA bis heute hartmetallbestückte Werkzeuge und Stahlwerkzeuge für die Steinbearbeitung sowie Drucklufthämmer höchster Qualität für Steinmetze...

www.bildhau.de

For the round tip hammer I used a KLOT carbide bit 65 Hrc from ebay, turned backwards and rounded

 

[FredyCro]

I am in Europe too and struggle to find a carbide ball or chisel to build a staightening hammer.

Could you tell me what you ordered and where?

Thanks

Dan

Cheap solution - The largest masonry drill bit with carbide tip you can get. Preferbly over 14mm. Round of the tip with a diamond stone or a busted 120 ceramic belt.