Friday, June 15, 2012

Seat Shaping Thoughts

I've added a final short summation to the earlier videos on shaping a wooden seat.  I hope that in the series, there may be some useful information for people wishing to do similar work.  I am interested in learning if anyone finds what I have shown here to be helpful within their own approach to chair making, or what other methods that they may have found useful to produce seats.  A bit of a choppy edited vid, sorry!   Thanks for viewing.


MS said...

Thanks for making these videos. I'm interested in seat shaping with hand tools as the grinder method holds no interest for me either. It was useful to see the soridai-kanna in use, further encouragement to make or find some.

djy said...

MS, thanks for the comment. I'm curious, are soridai-kana (for folks not aware, the round bottom Japanese planes) not available from your location, or much sold on the web? I recently purchased some sharpening stones from an Australian fellow in Japan that has a tool site business. I don't believe that he markets soridai, but I could encourage him to do so if people would be interested in purchasing. It occurs that many folks interested in using Japanese planes, aren't so familiar with the soridai or nankin, more found within a furniture makers array of tools, than in a carpenter's kit.

His selling short die rectangular planes would be another way to go, then people can shape them to their liking. Available in a few different width would be great. Surface shipping from Japan isn't so costly, if he might have it as an option.

MS said...

The only lower priced selection of soridai-kanna I have found is from Stu Tierney's shop.

Japanese spokeshaves (nankin) are a bit harder to come by, selling in the $100-200 range new.

I think you're right that customizing a small dai is probably the quickest and most economical way to go. I had success making a rokudai jointer plane, so I obtained some white oak and am eager to try my hand at more dai making.


djy said...

Stu is the person that I had in mind, now I see that he already sells the soridai. Sadly, planes have much done a disappearing act in shops here. One place the next town over, used to have one entire wall covered with a vast selection, the same company that had a salesman come by the shop every month, at the place where I apprenticed. Guys would be literally jumping out the windows to keep from getting snagged to pay for past purchases. Now the shop is still there, but not a single plane in sight.Still a couple specialty suppliers in Tokyo that I know of. Japanese tend to take a lot of cool stuff for granted, that gets lost in the transition between eras.

One of the older craftsmen in particular had a phenomenal assortment of planes. It's years since he lost his sight and is retired, his tools probably boxed up somewhere. Families of the workers tend to keep them for the sentimental value, then rust invades and they disappear to who knows where? I know a couple of cases of that happening. My own teacher's tools for a fact. During his last days when I was visiting, his wife took me aside and said his treasure was to be bestowed upon me, but she ended up passing away before he did, and the children didn't share the same sentiment to part with them, though they would never be used. I had to let it go.

Good luck, Mike, I hope you can manage to increase your assortment of Japanese planes.

matsukaze said...

Dennis, thanks for putting out some really nice info. What I would really like to know from someone like you is how you shape, maintain, and sharpen contoured dai. Modifying toishi etc... HUGE subject for sure. Please no pressure. I have been working with some convex and concave koganna and also just build a beading kanna ( hemiganna? ) for beads on the interior edge of door rails and stiles. Thanks for shedding any light on the vast darkness in the scope of my field.

djy said...

Hi Correy,

Normally for a round bottomed plane like a soridai, the process I use would be to bandsaw the curve along the length, then refine and smooth with a nankin, and probably use a piece of sandpaper on flat surface like the table saw, to even it all out. With a curve also going across the width of the dai, once again a nankin or another soridai, then sandpaper. You probably already know that the areas of the dai both in front and behind the iron, and in relation to the horizontal plane, require a certain elevation configuration to get good planing results without chatter, much like a hiragana has certain requirements. Not all my round bottom planes have one, but I like to put a metal insert in front of the throat, to keep the area constant without wear. Especially with a plane that might be used as the next step after adzing or however one might initially rough out a seat, having the metal surface is important as the die will wear quickly with a lot of pressure pulled over the rough surface.

As far as the toishi go, i tend to use the used course flat stones, say 800 or 100 grit, that still have some thickness left. Starting out flat with a curved iron, a curve will wear in the stones, but they also do a good job when still in a more flattened state. Sometimes it seems to help by running the iron across the stone with the iron help perpendicular to it, along with sometimes parallel, whatever it takes to keep steel removal even, or when the iron shape has become corrupted and needs to be trued up to better fit the dai shape again.

For concave irons, I have taken some older stones and turned them on edge, then reshaped them to a curve using a grinding wheel or whatever ones might use to true up their stones. They tend to often be narrower than the iron, but work ok. The same with a finishing stone, but for the soridai iron, I tend to more often than not simply use a flat stone for the finer grit sharpening.

Currently I don't use much in the way of beading planes or the like, that is really cool that you do. In the past when more using them, I would need to reshape a stone to do the sharpening, with whatever might work, including a piece off a metal cut off wheel. I have a lot of small pieces of irregular shaped stones that I have acquired over the years. I must confess to not keeping them in a good order for better sharpening beading plane irons, etc. I became lazy about it. Such planes are very enjoyable to use, are they not? I wouldn't mind getting back to it at some point if the work called for it. In a sense, things seem to be getting simpler, probably my mind as well, ha!

Hope something here might be useful, thanks for contacting and keep up the good work! Nice hearing from you. I'd be interested in seeing what you are making, you always write about it well.