Tuesday, July 28, 2015

Break one tooth and you are an idiot

Break 20 and you are creating the Gonzalez™Universal Random Matrix tooth pattern. Created by your humble blogger (did you know that in germany blogger is a clothing style too?) myself.

The Gonzalez™Universal Random Matrix saw consists of gullets arranged in the same pattern as the first 12 eigenvalues of a random matrix. It's like the Fibonacci series but cooler and made precisely to cut well. It also solves the basic levels of an hydrogen atom when the chromodynamics equations are taken into account.

It also presents a carefully filed curve in the top part of the saw that both dissipates heat while cutting and compensates the movement of the hand at the end of a stroke

Let's see it closer

The depth of the gullets follow a catenary function to improve sawability

Here is the dissipation zone

It does cut like it is expected from a Gonzalez™Universal Random Matrix saw, as soon as Julia brings her Ipat i shot a video of it.

All this thanks to 1 single sided file I found in my box. Man they are sweet for dozuki. I used to think dozuki were difficult to file. I was simply using the wrong tool.

On the other news I'm moving to Valpo for a few weeks, second carpentry course will have sushi it seems. I'm building the structure from the previous exercise and taking Keiran with me to continue his apprenticeship

I also made a dai sunday, but chilean roble doesn't have "rays", is the one on top without sub-blade. The endgrain

 We also thought about acacia, but no rays either, extremely hard though. (Also, the left side is planed, the cuts directly from the dosuki I sharpened today.)

 American oak does but I don't like it

 Japanese white oak

 some other wood, more metallic, for a blue paper steel blade

 And I've been making some handles of old smelly oregon pine (or something like that)


In case you ask... I bought the dozuki originally form fine-tools, before moving to Graz. I tried to make a bed in douglas fir with it, construction market lumber. Then it broke. The saw can be found here: Shirai Sangyo Dozuki however, after seeing more carefully how I broke the teeth, like 90% of them broke on the same side, which indicates to me that the set was not properly made in this saw.

If you want to get one, bring me a dozuki, a single sided file, and a few beers. Let's say 30 litres. Or 20 litres and 5 kilos of meat that you need to bbw while I file.

Now, if you don't think on visiting chile in the near future, you always can get one from nagakatsu, but he doesn't have the random matrix pattern. Take a look: http://www.mitsurouwax.com/nagakatsu/doutsuki1.html

Another option would be to make a small workshop in Germany during October, not in Munich though, too many drunkards and too close to the Reich in October. In Celle instead. Saw vice making, saw sharpening and madonoko making. I got 34 hits from Germany last week so I guess somebody over there is reading this.  Wir konnen ein kleines bischen Deutsch, and I guess Julia would be trilled to work as a translator. Shall I put an ad somewhere?


  1. And it's pretty!

    Were the teeth already broken, so you made a sad situation wonderful? It looks nice!

    Finding a wood that is an adequate replacement for Japanese white oak is difficult. American red oak feels awful, white oak only slightly better. I had intended to try Beech...or....hard mahogany with a laminated purpleheart sole. The Japanese white oak is just a great wood! Hard, but not too hard. Very dense wood just doesn't work well, does it.

    1. I don't know if it's me, but beech gets dirty whereas jap oak gets shiny.

      I broke two or 3 more to make the gullets a tad more evenly spaced. The gullets now are 1 tooth wide, maybe 2 wide would be better... we need more variations to understand what's best.

  2. Ah! So that's what my one sided file is for! I bought it thinking it was a regular 75mm file, but it only has teeth on one side. With almost no thought, it cuts new teeth very quickly.

    Have you guys ever used shagbark hickory? I'm planning on drying some blocks of hickory specifically for plane bodies. I'm thinking it will work perfect for a dai, since hickory flexes, while being hard and dense.

    1. Exactly. And indeed, the thinner edge cuts down real fast, way faster than the double one.

      Never seen hickory, I think. From the online pictures, it doesn't have the radial rays on the endgrain. Somewhere I saw that that's what you are looking for on plane body, since they are like little dots of endgrain on the face, making it more hardwearing.

      That said, make 10 dai first in whatever wood you got, then buy japanese oak. This is like my 4th and still cannot make the blade to fit all the way properly, still have to glue newspaper on one side (which also helps with the springy-ness of the day, roble is not springy at all).

    2. I think hickory would be quite nice, especially if you had a piece from the under/compression side of a hickory branch. If you're splitting blanks from smaller diameter logs make sure you clear the pith. I left that on a couple of elm dai blanks I made and it has a habit of originating drying cracks.

      Sebastian is definitely on point saying, use what you've got and then get the good stuff. Japanese White oak is highly optimized for dai in so many ways, its hard to find domestic woods to match it. That said, the crappy read oak laminated dai I made works just fine, though it requires more work to keep the sole tuned.

    3. I think I will keep practicing in whatever wood until the hickory has dried (plane makers say they dry the blocks for four years, I think), then compare the hickory dai to a Japanese oak dai. I'm trying to avoid using any non-domestics in my work, to minimize my impact.

      It's strange, but apparently Japanese oak isn't in the wood database. I searched for Japanese oak and Mongolian oak, along with quercus mongolica.

  3. Love it, randomizing the matrix is what we need more of!

    The Oaks are the most difficult of all trees to convert to lumber. (of those that can be converted, or worth converting), and the thicker the lumber the more difficult. I got a book on Wood Conversion somewhere.

    Did you try searching under Shirogashi?

    I have a block of Hickory, ~ 4 x 7 x 13" I use for a wood anvil; probably make great dai. I made no attempt to season it, so it has cracks. I'm gonna say it is not as hard as kashi, has more bounce - more elastic.