Brendon_t

How on earth to cut this joint

Recommended Posts

I was talking to an old guy at my work who is an oldtimey wood worker. Talking radial arm saw, belt sanding, ax wielding dude. 

He challenged me to make this joint.  I've already slaughtered two attemps due to just my crappy layout lines. Wondering if anyone has any aah ha tips. 

Do you go socket side first or  stop sign first? Knowing how intricate it's going to be, would light wood, dark wood, or one of each visually help cover any imperfections.

image.jpg

Share this post


Link to post
Share on other sites

I'd do the stop sign first then use that to layout the "mortise". Of course you could make a template and use a router?

Share this post


Link to post
Share on other sites

Ok, the challenge is on!

Here's how the old timers did it.

Edited by K COOPER

Share this post


Link to post
Share on other sites

I'll knock one out tomorrow before breakfast. ;)

I'd certainly cut the tenon first. I can't see how to lay out the mortise first, and get proper layout the other way.

This is an interesting thing. I do want to try it soon.

Share this post


Link to post
Share on other sites

I would do the mortise first and I would use my HCM.  Then, I would cut the tenon to fit.

Share this post


Link to post
Share on other sites

Believe it or not, these sorts of joints were made by marking the lines on each piece separately, and then cutting each piece individually. There wasn’t any transferring of lines from one piece to another as in making a dovetail joint. If you think about it, these joints were used to join together long beams, which would have been too big to maneuver around to transfer lines. So the accuracy of the layout was key.

You can make things a bit easier for yourself by taking advantage of the parts of the joint that are evenly spaced. On the top, the two stub pieces, the gaps, and the neck of the long stop sign part are even, so divide the beam into five parts and work off of that. On the side, the shoulders are half way down.

Finally, and this is going to be different from how you probably are used to marking joints, strike a center line along the length on the faces of the two parts, and use that as your reference in marking the lines for the joint.

  • Like 2

Share this post


Link to post
Share on other sites

I was going to say "what is the point? does this joint have a practical use?" but I thought I should actually make one first.

fwiw I cut the tennon first.

A pretty gappy effort, but I was rushing it a bit. However, despite all the gaps it is surprisingly solid, I guess with all that complexity some parts of the joint are bound to be good and tight.

My first piece of advice is use a hardwood - what was I thinking using a softwood scrap to cut a joint like this!

PA084930.thumb.JPG.9ad1e601be894e583a85d

PA084931.thumb.JPG.4d832a530ba037fbb9538

So, back to my original question ... does this joint have a practical use?

Edit:

Since you asked for tips - I thought I'd add some serious ones for you.

0) Make sure your two pieces of wood are perfectly square - and the same width/height.

1) Layout the tenon piece as accurately as possible (I just used a ruler and pencil - hence all the gaps). It doesn't really matter how you layout the stop-sign, since I recommend scribing this onto the mortice piece.

2) Then its fiddly work with the dovetail saw and paring chisel.

2a) Actually I used a coping saw to rough out the tenon, then pared it to shape with a chisel.

3) Once the tennon piece is cut, layout the neck of the mortice, and cut it out just as deep as the stub tennon below the stop-sign.

4) now you can slide the tennon piece onto the mortice piece and scribe in the shape of the stop-sign and the corner cut-outs.

5) Then it's more fiddly work with the dovetail saw and paring chisel.

That's how I did it - no idea how you'd do it with a radial arm saw, belt-sander and axe.

 

  • Like 1

Share this post


Link to post
Share on other sites

Haha yes it has a practical joint. Whoever has a cleaner joint is buying tomorrow at happy hour.

i cut three tonight. First two were damn gappy and ugly. This is the first decent one. Pinned with bamboo and one coat of ars.

being not a hand tool guy, this was a pretty cool exercise. I'd definatey at least giving it a try.  

I changed it do a slight dovetail because on both the first two, the stop sign thing seemed really not strong. One wing actually snapped along the grain line when fitting it together.

and I agree, this joint is strong as crap. The first time it slid home with only mild pressure, it just plain LOCKED.

image.jpg

Edited by Brendon_t
  • Like 2

Share this post


Link to post
Share on other sites

Interesting puzzle but probably easy to do with hand tools - no I'm not volunteering - maybe in the future though - who knows....

Share this post


Link to post
Share on other sites

Brendon, good call on the dovetail shape. Looks better to me, and I bet it fits easier that the hexagon original. Now my question is, under what circumstances would someone used this joint? Timber framing, maybe? I can't come up with any furniture pieces that would benefit from it.

Share this post


Link to post
Share on other sites

I can see this useful as a repair joint, similar to a scarf. Pro's- Stronger than a scarf  Con's- More visible. 

Might also be a nifty way to attach a foot to a table leg. 

Edited by Janello

Share this post


Link to post
Share on other sites

Brendon, good call on the dovetail shape. Looks better to me, and I bet it fits easier that the hexagon original. Now my question is, under what circumstances would someone used this joint? Timber framing, maybe? I can't come up with any furniture pieces that would benefit from it.

maybe if you want to tie in another wood species for added visual effects, like maple in the middle of a table apron made of walnut to lighten the piece up color wise. 

Share this post


Link to post
Share on other sites

http://www.amazon.com/gp/product/B007055QIY?keywords=japanese joinery kiyosi seike&qid=1444501428&ref_=sr_1_2&sr=8-2

 

I have it.  It's a neat book just to look at but it's not really a "how to."  A lot of timber frame joints, scarf joints, and craziness that is both rarely used and rarely needed.  But still cool.

The one you linked appears to be a newer edition.  I would assume the same content.

Share this post


Link to post
Share on other sites

Haha yes it has a practical joint. Whoever has a cleaner joint is buying tomorrow at happy hour.

i cut three tonight. First two were damn gappy and ugly. This is the first decent one. Pinned with bamboo and one coat of ars.

being not a hand tool guy, this was a pretty cool exercise. I'd definatey at least giving it a try.  

I changed it do a slight dovetail because on both the first two, the stop sign thing seemed really not strong. One wing actually snapped along the grain line when fitting it together.

and I agree, this joint is strong as crap. The first time it slid home with only mild pressure, it just plain LOCKED.

image.jpg

Good job!

Share this post


Link to post
Share on other sites

       The only use that I can see is the appearance.  Using two different woods that compliment each other, would bring a visual interest to something that you wouldn't expect.. Kinda like a teenager's "eye candy" to we wood folks!  And Brendan, ya done good!

Share this post


Link to post
Share on other sites

You guys must have glossed right over Wilbur's post...frankly the only one worth reading in this entire thread: that joint is essentially a scarf joint for joining long beams in traditional Japanese timber framing.  It wasn't designed to be used in furniture.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.