Friday, December 5, 2014

Last is first, first is last----having a bad "kanna" day.

Sometimes they are your best friend, sometimes you want to chuck them out the window. I'm having a bad kanna day. Not really bad, just a little annoyed is all.

We are moving, literally in just a few days, and I just received my last kanna from my tool seller friend Junji (eBay seller yusui).

Unlike the other kanna that I've bought, this one is a "known" blade, and WAY better than anything that I would normally dare to purchase. So my first famous blade is also my last purchase (for the foreseeable future). First is last, get it?

"Kanzan", by Hideo Ishido Teruhide. 

Hideo Ishido passed on in 2006, I believe. I'll do my best.

It's a little hard to see in this photo, but just below the lamination line, to the left is the stamp of the Tokyo plane manufacturers co-op.

There is a nice feather pattern on the display face.

It is in pretty good condition, and lightly used. Definitely used though, so I can be comfortable putting this guy to work. Whew! I don't know what I'd do with a really nice kanna, you can only look at them so much, before you need too remember that they are just tools, haha.

Matching sub-blade.

There are stamped markings on the front side as well.

(Damn this iOS mobile app!! My apologies for the strange picture sizes.)

This kanna is very close to being ready as is, but the blade protrusion is slightly uneven. I need to shave a small amount from one side of the blade retaining groove. As I use these tools more, I am coming to the realization that "less is more", meaning that you should only do the barest minimum required to get the job accomplished. This is not to be confused with the easiest way, or the least amount of work. Perfection is a floating target at best ( and an illusion at worst), but you do the best that you can.

With my first few kanna, I adjusted the fit of the main blade to accommodate more lateral blade adjustment than was really needed. I was carving out the sides of the grooves so that there was about 2mm of gap on either side, but that's not the proper way of accommodating a blade that sits unevenly. Maybe it would help if I explained how this came about.

My first kanna had been sharpened unevenly, so that the blade edge was no longer perpendicular to the long axis. Seeing this, I thought, "Sloppy bastard, too lazy to do a good job, etc etc", then proceeded to square things up. It turns out that the dai had been cut slightly uneven, so the guy who was sharpening the blade funny was right, and I was wrong.

Now I had a kanna that was taking a bigger bite on one side, so to even things out, I needed to tap the blade over to one side. That meant deepening the grooves. Now the blade is sloppy, and I still need to tap that blade over to the right, each and every time that I use it. Forever. A better fix would've been to sharpen the blade so that it was no longer perpendicular to the long axis. Smart guy, I am.

We are so used to thinking of things as needing to be square, straight, flat, whatever, that it's easy to shoot yourself in the foot. These tools just aren't made that way. It's tough, but there is no standard/perfect/anything. You need to think. There are general rules and guidelines at least. Thank god, cause thinking isn't always my strong suit.

In my perfect world, the main blade of the kanna would slide down perfectly to within maybe 3mm of where it would start cutting. It would be perfectly centered, and would take an even thickness shaving the full width of the blade. There would be only 0.5-1 mm of clearance at each side of the blade, to accommodate any changes in humidity that might cause the blade to bind. If I *could* somehow get that perfect fit, then it would be a relatively simple matter to keep it that way. If I happened to sharpen the blade unevenly, pretty soon I would get shavings that taper to nothing on one side, so I would then refine my sharpening technique. I would be learning. It's cool!

I strive for a perfect world. It's an ideal, not a reality.

I laugh at those guys who need to have every tool ever invented, but sometimes it is nice to have some specialized help. I was sceptical of ever using a knife with a left hand bevel, but here is a good example of one, seen in use.

Right hand bevel, left hand bevel, and a 3mm chisel.

The left bevel knife really is handy for trimming flush to the underside of the groove.

Then the right bevel gets to do the other side of the groove.

The blade bed already has tape on it, so at least I don't need to feel guilty when I make the blade fit too loosely. Someone else beat me to the punch, haha.

Time for a preliminary bed check, using the straightedge light gap technique. I am going to borrow a picture from Kiyoto Tanaka (because he's a DUDE!, and the best in the world!) that serves to illustrate my ideal bed configuration.

This's perfection. There is a minimum of contact at both the front and rear of the bed, and just a sliver touching right before the blade......THIS IS THE MOST IMPORTANT AREA! You can also see how the hollow in the bed of the blade gradually becomes deeper, then sweeps up to contact just before the cutting edge. 


This is what I've got.

Close, but needs some tuning. The notch is where the blade protrudes, so you can see that the bed is touching behind the blade. We want the opposite. We want the light to shine behind the blade.

One more thing. When I get the sub-blade aaaaaalmost to where I want it, it overrides the main blade on one side.

You can see the sub-blade osae-gane peeking out at the left. Crap! I hate when that happens!

The osae-gane fits perfectly, so never being one to take my own advice (much less others).....

......I take a bit off the side.

Just a smidge, I swear!

A little scraping, for starters.

And finally, a first test on some stringy, mystery mahogany.

Not too bad.

 It's a start, and is certainly workable as it is, but I want to see what this baby can do. The idea of getting the thinnest shaving possible isn't about the thin shaving. It is a simple matter to get the plane to work, to cut a shaving, to smooth the wood. That is easy. To get it to work perfectly? That is what the thin shaving thing is about. Any fool can get the damn thing to cut.

I messed up the edge when the osae-gane overrode the main blade, so it's time to sharpen. 

As is with almost all of these, the bevel isn't perfectly flat, but because I'm, uh, time constrained, I just concentrate on the edge itself. It pains me, because I REALLY want to see what this blade looks like polished, and I can't quite get all of the edge right, either. It needs to be redone, but that will have to wait. The rentetsu is even and fine grained. The lamination shows perfect heat control, and has no evidence of carbon migration. Very nice welding.

I try to get the osae-gane as close to the cutting edge as possible.

I think that I can see a thread of edge down in there.....

The African khaya shavings are very glossy.

However, something just isn't quite right. The blade isn't taking a full length shaving, and only partial in width, too. The board is only a short thing, and a quick visual confirms that it's not the board's fault, so it must be the kanna. I had a day like this a few months back, and it can be maddening. Everything is there, but something is off.

When the kanna isn't working right, the first thing I always check is the condition of the edge. It seems obvious, but almost every problem is rooted in sharpening, one way or another. 80% maybe?

I just sharpened, and although the blade isn't as perfectly sharp as I would wish, it doesn't explain the lack of proper performance. If the blade is fine, then it had to be the dai.

The dai looked ok when I performed the light gap test with the straightedge, but I'm often not as thorough as I could be, so it seems likely that I have missed some spots. A quick, yet nearly foolproof test is the "sandpaper stuck to a piece of glass " test.

High spots are lighter, the lower are dark. The hollow at the center of the dai is fine, but all of the light areas along the edges represent material that needs to be removed before this kanna will work properly. 

The section of the bed behind the blade needs attention, too.

Light test.

This usually goes back and forth a few times. Scrape, check the gap, then scrape a different area, probably.

Don't forget that little bit to either side of the blade mouth.

The difference is remarkable. When the bed of the plane is configured properly, you can feel the kanna sort of squat down as the cutting edge bites in. That's when the kanna will make its distinctive *Skweeeeep* sound and pull shavings the full length of this Bubinga, no problem, but......

This mystery wood (soft maple, perhaps) has a mild curl to the figure, and gives no problems, but still....

I feel like the sub-blade/osae-gane could be set a little finer, but it doesn't want to cooperate. This kanna is getting tired...... or maybe it's just me. Best not to push too hard, at this point.

It is a gray day, so photos of glossy, reflective surfaces are in short supply.

It's glossy, trust me.

 But *still*.....something is not quite right. I can check the blade bed, I haven't done that yet. I can fiddle more with the hollowed portions of the dai, they're not quite perfect yet. And I can do a better job sharpening, too.  

It has to be......*something*!

At least I can make it pretty.

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Like all of us, I am figuring this out as I go, so when you see something that is incorrect or flat out wrong (and you will!), let me know. This is a learning process. Real people and names, please. Constructive comments and questions are very welcome, but hate speak/politics are not! Life (get one!) is too short.

Thanks, Jason