Kanna-ba shape

[Tom Schorn]

After lurking here I finally ordered a Tsunesaburo hina-kanna from Stu and got it last week, thank you all for your help. After a few rounds on my shaptons, I was impressed with the steel. Following directions carefully, I matched the dai bed to the blade shape, and then tapped it out so the cutting edge is parallel to the dai mouth. After this I tested on some maple and made some very thin, blade-wide shavings on the first 8 pulls,. After that the shavings were still thin but dropping off on one side. Removing the blade I checked the geometry and found that the right side is square with the cutting edge, but not the left. Below are pics What should I do next?

(A) Leave the blade as is and address the problem by working more on the dai?
(B) Grind the bevel and edge so the blade has an overall keystone shape, and then reshape the dai bed?

Top view: http://imgur.com/a/Ot6Hs
Right view: http://imgur.com/a/dIiEp
Left view: http://imgur.com/a/Vgd2a

[Brian Holcombe]

Tom, I'm a bit lost. Tapping out and bedding the dai are largely unrelated. Tapping out is to setup the ura.

Please provide a photo of the bedded blade as it looks from the underside of the plane.

[Jim Koepke]

Howdy Tom and welcome to the Creek.

Brian and a few others here are your best hope. I get lost just trying to figure out what all those different references to Japanese planes are.

jtk

[Tom Schorn]

Thanks for the prompt reply!

Tapping out and bedding the dai are largely unrelated.

I understand, I just wanted you to know that I did both before testing.

Please provide a photo of the bedded blade as it looks from the underside of the plane.

Here it is if I hammer it in straight from the back. As you can see the cutting edge is crooked because one side of the blade is not squared. Is this by design, to enable it to go in tight? If I hammer from the back and then the corner, the edge will come out straight, but then the blade is seated at an angle in the dai bed.

http://imgur.com/a/Al5vu

[Brian Holcombe]

Two problems have arisen, they are seperate from one another.

first, grind the mimi in from the sides until the blade width is smaller than the opening of the dai. This prevents the shavings from getting caught at the corners.

The second is that you need to relieve the back corner of the dai grooves so that you can adjust the blade side to side. If the clearance is there then adjust the blade so that the cutting edge protrudes evenly.

Please have a look at my blog posts on the subject, I cover these topics in detail.

[Pat Barry]

Howdy Tom and welcome to the Creek.

Brian and a few others here are your best hope. I get lost just trying to figure out what all those different references to Japanese planes are.

jtk

This is one of the few things Jim and I can agree on.

[Tom Schorn]

my blog posts on the subject

Excellent, looks like I came to the right place. Although, when I click on your blogs I see only three short comments, no actual blogs. Am I missing something?
From what you're saying, and the diagrams on toolsfromjapan, it looks like the angle of the ashi/blade leg is not intended. Are they usually more symmetrical? I can see how it's better to adjust the dai instead of the blade though, thanks

[Brian Holcombe]

Check out www.brianholcombewoodworker.com under Japanese tool setup. That should answer most questions, and possible raise more

[Stanley Covington]

Tom:

The blade is obviously of poor quality, in more important ways than just the skiwampus shape. Standard QC for this particular maker.

Grind the skewed side parallel to the other.

In cross section, the side edges are typically angled 2 or 3 degrees from the back to the ura (ura face is slightly wider than the back). Square edges are OK, but an angle in the opposite direction is bad. Don't let the hard steel lamination get too hot.

Wait to shave the grooves that hold the blade in places until you have finished grinding the blade. The grinding may make this step unnecessary. Best to retain as much continuous wood fibres through the mouth/grooves as possible to avoid weakening the dai.

With this adjustment, the blade may tend to wiggle too easily right and left in the dai. That can be fixed with some wood/paper slips and glue. But remember, whatever you do, the blade should not wedge into the dai across its width as the forces produced will tend to split the dai.

FYI, if you intend to store a Japanese plane for several years, it is best to remove the blade to prevent wood shrinkage from causing the blade to crack the dai. You see this a lot in old planes.

The mimi need to be trimmed as Brian said.

Did the dai come with those little divots cut out of the mouth's corners? Unfortunate.

Stan

[Tom Schorn]

Thanks Stan for answering my question.

The blade is obviously of poor quality

What are folks paying for something better? Maybe my expectations were too high for this price point

Grind the skewed side parallel to the other.

Good to know, I'm glad I didn't screw up the dai working around the poor blade angle. I'll be grinding this down by hand on my shaptons, this will take a while. I live in a city with small space so I'm limited to hand tools only.

Did the dai come with those little divots cut out of the mouth's corners?

Yes, does this indicate the dai is not new? I was told that it was

[Stanley Covington]

Thanks Stan for answering my question.


What are folks paying for something better? Maybe my expectations were too high for this price point



Good to know, I'm glad I didn't screw up the dai working around the poor blade angle. I'll be grinding this down by hand on my shaptons, this will take a while. I live in a city with small space so I'm limited to hand tools only.


Yes, does this indicate the dai is not new? I was told that it was

I don't know what you paid for the thing, so I can't say if you have the right price point. A decent 70mm starts at around $250 over here. T's stuff is machine-made, stamp-n-grind, K-Mart Special, use-twice-and-throw-away kinda tools, despite the inflated prices for their top-end products.

You will be grinding a long time on Shaptons. I know it sounds disgusting, but save yourself some time and money and work it on a flat rock or a concrete sidewalk with running water to waste most of the metal. Its just a Tsunesaburo after all. Check it with a straightedge frequently to ensure it does not get rounded.

The dai may be new. The little notches at the corners are intended to provide a hiding place for wisps of shavings that get stuck in the mouth. Amateurish, but some people think it looks professional. It removes material at the most critical area of the dai for no gain. Trading bacon for sizzle.

[Tom Schorn]

I don't know what you paid for the thing...K-Mart Special

I paid $78 plus shipping. I was told from multiple sources this dealer is reputable, selling only decent quality gear. Bummer, I was really excited about this and it took 6 weeks to arrive. One of my other hobbies is restoring and honing antique straight edge razors, so I'm confident I can get this setup properly, but now I question the integrity of the steel. I really don't want to lap this thing too often.

Here's the reason I bought this, excerpts from the sellers site:

"no Tsunesaburo kanna should require any adjustment of the body before they can be put to work...as Tsunesaburo is quite demanding in regard to quality control and takes their 'ready to use' warranty very seriously...they are always made to order...Tsunesaburo have recently taken on 3 new apprentices"

[Brian Holcombe]

Tom, in all seriousness you will likely be adding a zero to that number for a more serious Kanna. I completely agree with Stan, the notch on the bottom of the dai is pointless, I did it on maybe my first dai but stopped doing so shortly thereafter. I realize that you did not cut the notch, but something to be mindful of for the next dai.

Stan is a great mentor, so you are in good hands! Take his advice as it is excellent.

[Stanley Covington]

I paid $78 plus shipping. I was told from multiple sources this dealer is reputable, selling only decent quality gear. Bummer, I was really excited about this and it took 6 weeks to arrive. One of my other hobbies is restoring and honing antique straight edge razors, so I'm confident I can get this setup properly, but now I question the integrity of the steel. I really don't want to lap this thing too often.

Here's the reason I bought this, excerpts from the sellers site:

"no Tsunesaburo kanna should require any adjustment of the body before they can be put to work...as Tsunesaburo is quite demanding in regard to quality control and takes their 'ready to use' warranty very seriously...they are always made to order...Tsunesaburo have recently taken on 3 new apprentices"

$78 is very inexpensive. You got what you paid for.

The retailer is just passing along what T told him without being critical, just as he passed along the plane to you without examining it.

Tsunesaburo is a manufactory, not a blacksmithing operation. My problem with T is the hype they blithely issue while selling home-center quality tools as professional-quality tools. People actually believe it.

I am not sure what steel T used for your kanna. Probably SK, which is inexpensive and decent, but not the level of purity Hitachi's products or the Swedish HC steels. It will probably cut just fine, but the crystalline structure of the steel, and ultimate performance of the blade, will not match a hand-forged blade made from top-grade HC steel and jigane by a blacksmith with 30+ years of hands-on experience. But recognize that a blade like that will cost $300-$600, not $78.

Notice how the edge HC laminate is relatively thick, and of uneven thickness, indeed, even wavy. This is indicative of very rough, hurried, low-quality work, but it is entirely consistent with an inexpensive kanna.

More troublesome is the black line visible between the HC laminate (hagane) and softer body (jigane). A little bit of carbon and junk at this line is perhaps tolerable, but the amount visible in the pictures is a clear sign the forge welding was not done properly. Functionality aside, a professional would be embarrassed to have other craftsmen see that he owned a blade like that because it would reflect poorly on his discernment.

Make no mistake: A delamination would be fatal to the blade. Delaminations happen, but such a blade would never leave the forge of a skilled craftsman who cared about his reputation, however cheap it might be.

"Made to Order?" Charming way of describing a "lot" production. 3 new apprentices? 3 new minimum-wage workers (probably not Japanese citizens) is perhaps a more accurate phraseology.

Take heart. It's a good plane to learn on. Use it until you are ready for something better. Then continue to use it for rougher work. The money was not wasted.

[Tom Schorn]

Then this is the perfect plane for me to make all my beginner mistakes on. Thanks, very nice of you for taking the time to explain all of this.

UPDATE: I contacted the reseller and he quickly replied, and agreed that there's a problem with the geometry of this particular unit. He's going to talk with the manufacturer. Maybe they can fix this. I'll keep you guys posted. The kanna-mi is blue steel btw.