Cutting a Giant (300 mm) Japanese Scarf Joint (金輪継 or Kanawa Tsugi) - for a Structural Beam

In this video, I work through the process of cutting (Kizami - 刻み) a Japanese Scarf Joint (Kanawa Tsugi - 金輪継). This is one of most common joints found in a Japanese house. Perfecting your skill in cutting this joint is important because on a typical house you may have to cut this joint 50 times or more. This particular joint is the biggest one that will be used in a new Japanese house. This beam measures 300mm tall.
For a Kanawa Tsugi joint, the attention is in the details. Slow and careful cuts will prevent unnecessary repeating and waste. This beam is relatively small considering some of the bigger beams planned for this Japanese house. However, the cost of this beam is still significant and can be a tough financial lesson to learn if you make a mistake.
At Fujimoto Koumuten, we are asked to work slowly as we do Kizami. This joint would take an average carpenter an hour or longer to cut if done accurate and well. Some more experienced carpenters can cut this same joint in 30 minutes or less.
Hope you enjoy this video.

[@jackchevalier8105]

I am fascinated by the Japanese ancestral techniques. And even more, the harth you put in it. Your explanations are very instructives. Thank you very much.

[@jamescook5617]

I certainly don't need to watch this, why can't I look away. What fascinating work. Beautiful.

[@deborahf3738]

Thanks for showing such a multi faceted scarf joint. Whew!!

[@nickmolloy9563]

Nice job. I can see your confidence growing using your tools. Hand tools are more effort but much more satisfying. Very grateful for the videos you produce.

[@LabGecko]

Many times hand tools can be deceptively fast without much effort. Skipping all the setup time on power tools makes a difference people often don't account for.

[@marcobettencourturbina1107]

Beautiful work man. You’re very fortunate to have found your way into it. It’s my dream to do this work. Keep it up!

[@sawboneiomc8809]

Keep doing a great job.....after 30 years can you imagine how more skillful you will be?

[@joeschmoe6392]

Woooo hoooo! Loving the return to fresh eps!🙇 Arigato gozaimasu!

[@fredbosch5392]

Nothing beats the sound of a sharp chisel. Great job.

[@michaelbacon5001]

.. ❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤😮❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤😮❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤😮❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤😮❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤😂❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤

[@rolandgdean]

Absolutely and utterly fascinating.

[@RichardDenRooyen1973]

around 29:40 u took a sigh and said it was a lot of work.... i did something last week with a 600mm length cut into a douglas beam of 140x140mm.... twice... i know what you feel 😂 p.s. your videos made me decide to buy a Japanese saw set myself and use for the project im working on now . boy, i love these tools.... ill never go back to western saws

[@chriskirkemo2522]

Super interesting. I’ve noticed a marked amount of improvement in your capabilities from the first video I saw (please know you’re more talented than me regardless). Well done!

[@ivanxyz1]

Beautiful craftsmanship. Japanese carpentry is top-notch. I have to believe this kind of attention to details adds quite a bit of cost to the construction budget of a house. But the long-term satisfaction is well worth it.

[@user-co8vc5nd7l]

Absolutely beautiful work

[@liveoak4124]

Excellent learning experience Thank you

[@JLuo-hb3mo]

Take the time to do it right! Great work!

[@woodisgood85]

I'd like to see a video of hand sawing techniques. Like how you hold the work, different way you use them, and the different saws you use and where you use them. I'm super interested in Japanese saw right now :D

[@homjay2448]

Manifique travail , très bonne explication des outils et parfaite éxécusion. Bravo à vous.

[@mercylongmeimercylongmei8865]

.lm Lm Let My m l I'm B00ppp

[@swissthun60]

Thank's for sharing this - it has been fantastic to see..., 😎

[@aconybell8658]

Thanks!

[@thecarpentrylife]

Thank you so much for the donation and thank you for watching! This keeps me going!

[@kmonnier]

Ink line precision is a great tip

[@physicsphirst191]

I don't think he mentioned it, but when he cut the kerfs for removing the wide "dado", he located kerfs at each edge, and the middle, of visible knots. Presumably that's because he knows the strip will break at that location, and has to be removed in portions, so a narrower strip is removed easily. Also, the adjacent strips have no knot material, so they will break fully along their length with less risk of a partial break.

[@johnnysmythe7767]

Fantastic work! I love watching your vids. On a side note… where do you buy your pants? At Workman?

[@Seelos333]

+ What function does the concave surface serve as? Does it help with assembly?

[@zephyr1408]

Looks like straight grain DF with the sap wood? I know it’s not & obviously a solid pick for the job I bet! I am a Finish Carpenter in the States. Out of all other countries craftsmanship Japan is def in the top 3 . Probably top two! Just amazing joinery skills! And I do my comparison by skills in wood joinery! Nothing can beat a heating / cooling ability in all environments then wood ! Done right 2 or 3 hundred yr old homes still working! By the way solid work!

[@WelshPigeon]

very good work! which tataki nomi do you use? tasai? I Enjoied the video. thanks for sharing!

[@Pali65]

Great to watch how you do it. I am only a bit surprised that for scoring lines you use chisel and not knife. I've been learning from the videos by Paul Sellers and it seems to me that using knife is somehow more straightforward so I wonder if knives are used in Japanese carpentry at all.

[@dusty7264]

Nice work 👍 what kind of wood is that? I’m still wrestling with adjusting the Japanese planes, I have used Primas European planes and American Stanley planes for thirty years

[@sal1964]

Would of like to see the layout in detail

[@abdelaziz0365]

Hi dear can you do a special episode if you can talk us about your tools, like the little square you got here it looks pretty nifty thanks in advance

[@17penobscot]

I’m enjoying your videos more and more, you show many good techniques that help in my hobby. I’m curious about the wood species you work with, is it a type of Pine?

[@thecarpentrylife]

The wood most commonly used in Japan is Japanese Cedar (Sugi). Thank you for watching.

[@petem9063]

I’m sure this has been covered or answered before but I’m wondering, do the Timbers come from the supplier square and straight and planned already, or is that something the carpenter does in the shop before the joinery?

[@technocos]

Thank you for the step-by-step explanation. Does the wood got some water damage on the right side? I see some darkish/greyish stain 4:25

[@thecarpentrylife]

The wood we use is naturally dried. I am not sure what that dark stain is, but it was dry. Given that it is embedded deeper into the wood it might have been caused by damages that happened to the tree years ago.

[@Seelos333]

+ Awesome content! Keep up the good presentations What function does that concave surface that you formed in your process of the cuts serve? Do those concave cuts aid in the assembly of the joints when erecting the structure on site?

[@thecarpentrylife]

The concave cuts are designed to make sure that the surrounding outer faces (edges of the joint) touch and create the appearance of a seamless joint. If the middle potions are not cut with a slight concave profile you would inevitably have the inside faces touch first which would result in the outer edges showing a visible gap. The concave cuts do not aid in the assembly, it is purely for the planned aesthetics of the joint. I plan to do a video explaining this in more detail soon. Stay tuned. Thank you for watching.

[@m249paramachinegun]

could you please share why you made a slight dip in the surface as you point out around 28:30?

[@joschmoyo4532]

I am a joiner, cabinet maker, pipe organ builder by trade but I thoroughly enjoyed building my own timber frame house. I didn't use any of my Japanese tools though. The timber was to tough and knotty. Where you used a paring chisel to flatten your scarf, I used a record rebate plane and Sorby firmer framing chisel. I reverted to Western tools because frankly they can handle faster more aggressive use on difficult timber. Even so I destroyed a Stanley fatmax. Broke the steel shaft inside the plastic handle ! I was using it to clean up angled mortises. I drove it with a heavy Thor rawhide headed hammer. Brutal. English scribe framing is not as precious and complex as Japanese framing but it's faster and extremely strong. We used a big circular saw and a German Mafele chain mortiser. Occasionally I was able to use my bandsaw to cut tenons. It was a blast. Timber framing is hard hard work.

[@andrewcarmichael8683]

Why were you using the rip side of your saw blade when you were cutting out the last of the waste? Other than that, good job! Wish I was doing that!

[@HeroOfTime303]

Hey! I hope you are well. This video was great! Could you please tell me the preferred woods the Japanese use for timber framing? Thanks for the video. -Ian

[@thecarpentrylife]

We use Sugi (Japanese Cedar) and Hinoki (Japanese Cypress). Some areas of Japan may use Hiba (a type of Cypress) and Akamatsu (Japanese Red Pine). It really depends on where you are and what trees are prevalent or common in your region. Thank you for watching.

[@HeroOfTime303]

@@thecarpentrylife Thanks for the reply! Your videos are entertaining and informative!

[@mururoa7024]

You never use dust masks with the circular saw? (I value my lungs)

[@guidetomachining]

Hi hello can you guide me on trying to purchase a long paring chisel like that one you use ? What’s the width of that ? Thanks

[@thecarpentrylife]

The long chisel I am using in this video is called Anaya Nomi and it is intended for carving deep holes with the added benefit of being able to hammer the end of the chisel to provide greater power. The size I am using is 48mm and it is by Tasai. You may find it online from Kurashige Tools. It took about a year for me to receive the one I am using. Thank you for watching.

[@anonplayer8529]

An amateur asking a dumb question (probably), how come kigoroshi is not used in this joint, is it too complicated structure to be tightened with hammer pretightening? I understand the reason to cut that minuscule concave clearance to surfaces to ease the assembly, but does the wedged joint eventually press tight enough to counter the "wobble". And thank you for an excellent video again, hope to see more of these.

[@thecarpentrylife]

You really do not have to do kigoroshi if the joint was well cut. I often see kigoroshi only happening in situations when we are stacking one beam perpendicular or parallel with another (a vertical install). This joint is a horizontal install. The wedge is tapered and will pull the two halves together making what appears to be a seamless joint. We also put a lot of chamfers (mentori) on edges to assist in the two halves sliding into each other. This week I will try to post a short video showing two halves a of kanawatsugi and the way they look after time.

[@anonplayer8529]

@@thecarpentrylife Glad to hear, I was pondering whether to ask about the test fit fit of the joint or not, decided not to bombard with too much. And thank you, that cleared a lot. edit; You mentioned to other comment about the expensive wood/expensive mistakes, watching these videos gives one better excitement and suspence than Hollywood blockbusters, I actually sighed a relief when that last slab you sawed off dropped and took away those gnarly knots 😅👍.

[@e139439]

Anyone knows why there are circular saw blade entries on top two corners @3:40 ? *I'm guessing they are circular saw entries

[@e139439]

oh, answer @5:50 :)

[@sylvioks]

Nice job!! My friend, What is the weight of this hammer you use to chiseling? Do you use the concave or the flat side? Thanks

[@thecarpentrylife]

I am using a 375g hammer head. The one face is convex and the other is flat.

[@sylvioks]

@@thecarpentrylife thanks for your reply! Do you think this weight is good for furniture making? Yeap about the shape, but which one I use where? Thanks a lot

[@marhar2]

what's the price range of these beams?

[@dougshaw9701]

Explain why the small gap was left around 28:12 of the video , should it of not been flat?

[@thecarpentrylife]

The concave profile allows for the joint to be mated together seamlessly.

[@LabGecko]

Dowels and wedges get added after placing that puts a lot of pressure on the joints, so on most joints once placed there will be no empty space inside

[@KamikazeeNYC]

Hi, Is there any difference between the Japanese and US version circular saw?

[@thecarpentrylife]

One of the biggest differences I have found is the weight. Japanese circular saws seem lighter and more ergonomic. The base plate is different as well. Japanese circular saws allow for attachments, like the guide for long cuts (equivalent to using a track saw). The base plate is also taller in some cases. This allows for the edge to be put against a guide. I can only compare this to an older circular saw by Skilsaw that I had from 10 years ago. It has a magnesium base, but it is still heavy.

[@KamikazeeNYC]

@@thecarpentrylife I had a feeling it was a better machine. I'm going to try to get myself one. For my first timber frame project I'm planning to build a floating deck. What joints would you recommend to use? The deck will be 16 x 18 ft. It is essentially just a very small house foundation frame.

[@normandeer1151]

could you please spell out the name of the tools and the tool shop in Tokyo so I can learn what the Japanese names are and possibly buy some Made in Japan tools?

[@scottm3130]

What is the pay for a Japanese Carpenter ?

[@SKawa-bo6ng]

金輪継ぎは、大体、土台の継ぎ手です、桁は、追っかけ継ぎが、ふさわしい、何故なら、継ぎ手が、斜めに、なつているから、

[@petrosmalik]

Is it still commonplace for the beams to be prepared manually? I would have thought that most construction companies rely on CNC machines for this.

[@petrosmalik]

And, lest I forget: AWESOME job!

[@thecarpentrylife]

Timber framing of any region is often done by hand. There are machines in Japan that can do a lot of different joints, but they can't do a kanawatsugi due to its intricate shape. We actually still use a lot of machines cutting a kanawatsugi, like the circular saws, kakunomi machines, etc. Since 100 years ago (and earlier) up until today we have sped up, improved, and become more accurate in Japanese joinery. Electrical tooling, like the above mentioned, is a big reason for this. However, the world seems to want robots, but every now and again it will be nice to meet a craftsman.

[@thecarpentrylife]

Thank you for watching!

[@petrosmalik]

Fascinating. So, just so I understand: when someone like Shoyan Japanese Carpenter gets his beams for framing at the start of the construction process, all those joints etc had been prepared by people rather than CNC machines? WOW!

[@LabGecko]

@@petrosmalik As I understand it for Japanese joinery the tolerances are fine enough that machines often have too much error, and many of the cuts used are at angles or small clearances that don't work for CNC

[@WireWeHere]

10:35 A little bit of a relief?

[@NSResponder]

26:25 wouldn't that part go faster with a plane instead of a chisel?

[@thecarpentrylife]

Yes it would be faster, but I have taken my chisel to cut along the line which is where the halves of a kanawatsugi joint will meet. I would be afraid of over pulling the plane and creating what appears to be a gap. Also, I am not interested in going fast, wood is expensive, which makes mistakes expensive.

[@NSResponder]

@@thecarpentrylife I see.

[@Kaijuus]

Are you mixed?

[@reddpanda3243]

You jammed the saw guard. A real clown move.

[@bgt63]

Nice.....youre half done. Lol

[@theshadow4292]

No disrespect meant to you or the Japanese people, but in speaking for myself, by you using Japanese words for various tools and wood cuts, etc. you are only making the video less understood and far less appealing to watch.