A locking tenon joint?

To access this forum when logged in, please, sign up to the Woodworking User Group in your User Control Panel.

A locking tenon joint?

Postby davidheim1 » Wed Oct 18, 2017 8:05 am

stick table.png

I recently modeled this table, by a furniture maker named Casey Lurie. All the joints use what he calls a locking tenon joint. It's some sort of Japanese-style joint. Unfortunately, I can't find anything that shows what a locking tenon joint looks like. What I used instead is a six-sided slip tenon, which fits in a funny little mortise, as you can see in the image. Any suggestions for a locking tenon joint?
Thanks in advance for suggestions and advice.
Best,
dh
0

davidheim1 
 

Re: A locking tenon joint?

Postby pbacot » Wed Oct 18, 2017 5:59 pm

With a little woodworking knowledge myself, I don't see a tenon joint in your drawing. You need a projecting element from at leas one piece. A locking joint may include some sort of cutout in the tenon that rests in the mortise making a positive tie--and with a wedge or pin would not come back out of the that position. That's as far as I can go with a little knowledge being dangerous thing! Let Dave R step in....
0
MacOSX (El Capitan) ShetchUp Pro v16 Layout Twilight Pro v2 M2 Kerkythea PowerCADD
User avatar
pbacot 
Top SketchUcator
 

Re: A locking tenon joint?

Postby pbacot » Wed Oct 18, 2017 6:02 pm

I like that hexagon biscuit and your model though! Seems that joint is taking on a lot. I'd love to see what joint would work best there.
0
MacOSX (El Capitan) ShetchUp Pro v16 Layout Twilight Pro v2 M2 Kerkythea PowerCADD
User avatar
pbacot 
Top SketchUcator
 

Re: A locking tenon joint?

Postby robertWan » Wed Oct 18, 2017 6:20 pm

I would do it that way.

tenon.png


tenon2.jpg


Robert
1
User avatar
robertWan 
 

Re: A locking tenon joint?

Postby davidheim1 » Wed Oct 18, 2017 9:13 pm

Good thoughts, pbacot.
Bob, I think you almost nailed it, so to speak.
It hadn't occurred to me to make one member in the joint a different shape from the others. I'd convert your tenon to a dovetail, however. That shape will definitely lock the two halves of the joint together.
Best,
dh
0

davidheim1 
 

Re: A locking tenon joint?

Postby tuna1957 » Thu Oct 19, 2017 3:35 am

Cool table David :thumb: . I think I've seen a drawing of the Japanese joint your referring to, but it's been so long I can't remember the exact details. Was inspired to put my own spin on it by everyones posts.
The stretcher has the tenon that"s cut like a butterfly dovetail. If that makes sense, narrow in the center tapers out at top and bottom. Corresponding mortises cut into leg pieces that slide straight in from the ends. I'd pin them with through dowels for a little extra holding power.
You have my curiosity up. I'll have to dig into my old reference material for the Japanese joint.
3

tuna1957 
Premium Member
Premium Member
 

Re: A locking tenon joint?

Postby davidheim1 » Thu Oct 19, 2017 4:04 pm

Excellent joint, tuna--especially working from memory. I think if you shaped the tenon like a double-dovetail, you wouldn't need the extra pins.
Many thanks.
Best,
dh
0

davidheim1 
 

Re: A locking tenon joint?

Postby davidheim1 » Thu Oct 19, 2017 10:20 pm

locking tenon.png

How does this look? It's a variation of tuna's joint.
Best,
dh
0

davidheim1 
 

Re: A locking tenon joint?

Postby tuna1957 » Thu Oct 19, 2017 11:17 pm

David, This rattled in the back of my melon head all day. Think I got it figured out :shock: .

The tenon end is hidden when assembled. Should only require glue for a strong joint. Each leg piece slips onto the dovetailed tenon. The angle cheek cuts on the stretcher should resist sagging of the leg pieces. Better be damn handy with a chisel if your going to make this joint. Cheers, tuna.
0

tuna1957 
Premium Member
Premium Member
 

Re: A locking tenon joint?

Postby davidheim1 » Fri Oct 20, 2017 5:28 am

You nailed it, tuna!
Nice work.
Best,
dh
0

davidheim1 
 

Re: A locking tenon joint?

Postby tuna1957 » Fri Oct 20, 2017 10:22 pm

Thanks David. Couldn't help making one more minor variation to the joint. Added a square dowel through the joint. It is centered on the midline of the tenon. Driven in after the parts are assembled the joints not coming apart even if the glue fails. This kind of locking peg is pretty common in large scale Japanese joinery. I'm not sure if it's common in furniture construction.
0

tuna1957 
Premium Member
Premium Member
 

Re: A locking tenon joint?

Postby davidheim1 » Sat Oct 21, 2017 3:00 am

Nice touch, tuna.
Got me thinking . . . .
If you use a drawbore pin in each half of the joint, you might not even need glue. (The hole in the piece with the dovetail socket would be offset about 1/64" from the hole in the dovetailed tenon. Forcing the pin into the hole draws the two parts of the joint together.)
Best,
dh
0

davidheim1 
 

Re: A locking tenon joint?

Postby tuna1957 » Sat Oct 21, 2017 2:27 pm

David , Your correct about draw boring for the peg. Offset hole in tenon, peg a little longer than needed , taper one end real good and there you have it. I'm sure most of the pegged joints the Japanese craftsmen cut for timber framing were draw bore. Still don't think my saw and chisel skills are good enough for this kind of work....
0

tuna1957 
Premium Member
Premium Member
 

Re: A locking tenon joint?

Postby Charlie__V » Tue Oct 31, 2017 2:51 am

I'm certain my geometry is off as to rake angle's/etc.......that said; I had a go at it just for fun as to what the "lock tenon" might look like.
2
Precision M1710/Win 7 Pro 64 bit/i-7 6920 Quad core 2.9 Ghz -3.8/16Gb ram/NVIDIA M5000M 8Gb

Charlie__V 
 

Re: A locking tenon joint?

Postby davidheim1 » Wed Nov 01, 2017 2:41 am

An elegant alternative, Charlie. If there's a way to shape the tenon like a butterfly key, then you'd have a real locking joint.
Thanks for taking the time to work through this.
Best,
dh
0

davidheim1 
 

Re: A locking tenon joint?

Postby Charlie__V » Wed Nov 01, 2017 2:20 pm

davidheim1 wrote:An elegant alternative, Charlie. If there's a way to shape the tenon like a butterfly key, then you'd have a real locking joint.
Thanks for taking the time to work through this.
Best,
dh


Thanks dh

I started to wonder if the "lock" in lock tenon was maybe taken a bit too literal?
So I made a second attempt with that in mind...... :mrgreen: IDK....maybe the upper & lower part of leg get "rotated" to fit together and then slipped over tenon? (just a carpenter here, and not a master woodworker)

C
1
Precision M1710/Win 7 Pro 64 bit/i-7 6920 Quad core 2.9 Ghz -3.8/16Gb ram/NVIDIA M5000M 8Gb

Charlie__V 
 

Re: A locking tenon joint?

Postby davidheim1 » Thu Nov 02, 2017 4:25 am

Very colorful and ingenious. Thanks for taking the time to model this. But it doesn't look as if the tenons on the brown part can be fitted into the mortises in the purple and green parts. The tenon fitting into the purple part works, but I don't see a way to get the tenon into the mortise in the green part. The long tenon on the purple part will prevent the other pieces from rotating into position. But if you make the purple tenon butterfly-shaped, then I think you'll be on to something.
0

davidheim1 
 

Re: A locking tenon joint?

Postby Charlie__V » Thu Nov 02, 2017 12:20 pm

davidheim1 wrote:Very colorful and ingenious. Thanks for taking the time to model this. But it doesn't look as if the tenons on the brown part can be fitted into the mortises in the purple and green parts. The tenon fitting into the purple part works, but I don't see a way to get the tenon into the mortise in the green part. The long tenon on the purple part will prevent the other pieces from rotating into position. But if you make the purple tenon butterfly-shaped, then I think you'll be on to something.


Dh
I was thinking the brown and green get assembled as a unit first. (Rotating both so tenons could “fit” together)
Then, brown and green assembly slips over the purple parts (long)tenon and lastly brown/green smaller tenons engage purple part.

I’ll see if my Fredo Animator plug in still works and try to post a video of assembly.
If not, ill just put a few scenes together to demonstrate what may be lacking in my verbal assembly description.

And yes, butterfly shape on purple long tenon would definitely make is a true locking tenon.....just don’t Know how that is possible in this configuration.

C

EDIT: UPLOADED .gif
Lock_Tenon_draft3.gif
2
Precision M1710/Win 7 Pro 64 bit/i-7 6920 Quad core 2.9 Ghz -3.8/16Gb ram/NVIDIA M5000M 8Gb

Charlie__V 
 

Re: A locking tenon joint?

Postby davidheim1 » Thu Nov 02, 2017 2:54 pm

Charlie,
Now I get it. Your locking joint works just fine. Thanks for the gif.
Best,
dh
1

davidheim1 
 

Re: A locking tenon joint?

Postby TIG » Thu Nov 02, 2017 7:37 pm

To force the final [purple?] tenon to lock firmly into the mortise...

Make it with a central small tapering horizontal cut along its length, make it widest at the visible end.
Make the tenon-mortise's cross-section so that its external end is slightly bigger that its start size.
After the joint whole is assembled, you can then drive a glued wedge into the tenon's exposed cut.
Over size the wedge's length so that after its firmly in and all is set, you can trim off the excess exposed end of that wedge and finish everything neatly.

Now all of these connections are locked in all directions ?
1
TIG
User avatar
TIG 
Global Moderator
 

Re: A locking tenon joint?

Postby Charlie__V » Thu Nov 02, 2017 10:34 pm

TIG wrote:To force the final [purple?] tenon to lock firmly into the mortise...

Make it with a central small tapering horizontal cut along its length, make it widest at the visible end.
Make the tenon-mortise's cross-section so that its external end is slightly bigger that its start size.
After the joint whole is assembled, you can then drive a glued wedge into the tenon's exposed cut.
Over size the wedge's length so that after its firmly in and all is set, you can trim off the excess exposed end of that wedge and finish everything neatly.

Now all of these connections are locked in all directions ?


TIG,
Thanks....& Aha....much like an Axe handle wedge, to keep the axe head from flying off.

And also goes to dh's thinking on butterfly joint as final "lock".

I only tapered the tenon's mortise 1° which actually seems like a bit too much? (maybe not)

Please see GIF
____________________________________________________________________________________________________
EDIT: I should have properly thanked Fredo for his Animator plug-in used to create the GIF’s in this thread ......so Thank you Fredo, for all the magic you have done with the Animator plug-in!
____________________________________________________________________________________________________
3
Precision M1710/Win 7 Pro 64 bit/i-7 6920 Quad core 2.9 Ghz -3.8/16Gb ram/NVIDIA M5000M 8Gb

Charlie__V 
 

Re: A locking tenon joint?

Postby davidheim1 » Fri Nov 03, 2017 3:23 pm

I think that does it. Thanks to TIG for suggesting the wedged tenon and to Charlie for producing yet another version of the joint.
Best,
dh
0

davidheim1 
 

SketchUcation One-Liner Adverts

by Ad Machine » 5 minutes ago



Ad Machine 
Robot
 



 

Return to Woodworking

Who is online

Users browsing this forum: No registered users and 1 guest

Visit our sponsors: