Saturday, February 21, 2015

A hard and sensitive girl

Still not dead.

Just looking for flat for julia for 6 months. Not as easy as one could think here in Graz.

But she's not the hard and sensitive. I'm talking of a saw.

A bit of history first. When I was asking Murakami to buy me the saw files I also asked him about a few saws I saw in yahoo japan. There you can get 4 or 10 saws for 1000 yen or so... The lot I was looking at was real crap, and Murakami told me, as a good drug dealer, "look, I found these today".


At 10usd for the four of em, I could not possibly said no.  Problem was that I needed to pay EMS for the long saws... so I left them in japan waiting for a while and they came together with my new slicks.

That was like a month ago.

Today I was tired of my cheap 300mm ryoba (pressed teeth, lousy sound, far too soft) and decided to try the bottom saw from the last picture.

It's a real sweet piece of steel. Tensioned like crazy, sounds like a frikkin bell. And it cuts fast:




However, like 33 seconds after start cutting, I realised I had snapped a few teeth. A FEW. 


I managed to break 3 on the rip side and 3 on the cross cut.

Now, you can think that stupid chilean, I bet he was still drunk from yesterday and bent the saw too much. Far from that. I was sober and had slept well, thanks god because last week was horrible.

The saw is hard. Like real hard. Like I make annoying sounds when you try to pass a file on me hard. No surprise I broke a few teeth.

This is the signature. I've seen that scorpion tail at the end in some axes, but have no idea who may be.

 The weld. Note how close to final size the forge work was done.

 da other side

One of the broken teeth.


Two of the other broken teeth.


When I had broken 6 teeth I said enough is enough, and put some fire to it. I think it didn't make the slightest difference. I touched up the rip side and every tooth had that annoying high pitch sounds when you are filing too hard steel. Crazy. 

My theory is that the surface of the teeth got far too work hardened and that's why they break so easily. (You can see in the last picture that the metal snaps in relatively large chips when you file it.) After I managed to file the edgy part of the teeth, the sound was a bit more normal, like you are filing steel, but nevertheless the saw is extremely hard. And extremely fast too. Hopefully with the use the uber hard part wears away and I can have a more forgiving saw. It didn't keep on breaking though, just 6 teeth in the first 5 minutes, and the rest of the afternoon she was behaving ok. 

I will keep an eye or two to see if I can find other saws with the same signature. Kinda like it. 




3 comments:

  1. What a great saw, I really like the looks of this one. A good call to buy it ( and the other saws look fun,too).

    Looking at the pictures of the steel where the teeth have broken, the grain of the steel looks a bit coarse. This might be indicative of less-than-perfect heat control during the forging process, and some steel types would be more sensitive than other types, ie; yellow steel has a lower carbon content than white so, as forged, a yellow steel blade would be not as hard as a white, but also more resilient and forgiving both to the blacksmith and the sawyer. I believe that would be why yellow steel is the more commonly used steel for saws. This baby could be a white steel blade. Nice!

    That's my thinking, anyways, haha. The grain size of the steel has already been established during the quenching process, but the utility of the saw might be improved a bit if you were to draw down the temper a bit. Say, 425*F for 30 minutes........Maybe 500*F or higher. Multiple cycles wouldn't hurt, either.

    When Julia asks what the funny smell is, say that you are cleaning the oven ('course then you gotta clean the oven,so......).

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    1. but now the problem is: I need a clay oven with a very high thermal mass to cook the blade in a very controlled way. And make pizzas.

      I didn't think of it, but I will definitely try it when I have an oven near by... still two weeks it seems.

      Oh, and I'm also learning to weld those broken teeth, that was my promise to the saw after the third tooth.

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    2. Welding teeth.......Interesting! Be sure to keep us posted!

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