# Which Joinery Technique is Best? Time, Strength, Repeatability



## RichT (Oct 14, 2016)

Interesting video. I do question the validity of testing cantilever butt joints. Most assemblies are going to have joints on two ends of the rail or apron, so the load will put the joint in a shear mode, and not torqued like a cantilever (or are going to use a stronger joint like a half-lap or bridle). In your statement about a chair and the 400-plus pound load, the load needed to cause that joint to fail in a real situation, where the board is joined to the legs at each end, would far exceed 400 lbs because, again, the failure would be due to shear stress, and not torque. Even a biscuit would stand up to that because the long grain to long grain glue up inside the joint down the full length of the biscuit would be far stronger than torquing out the biscuit along the narrow face. Not that I'd build a chair with biscuits however, just making a point.

When I do have a cantilever-type of load found in residential doors, where the hinge stile and rail joints are supporting the rest of the weight of the door, I use exclusively long tenons. I've torn apart commercially made doors that used dowels, and I suppose they are adequate, and heard of people using dominos (though you'd need the $1400 XL 700 to use the long dominos you'd need for the job).

Finally, why didn't you include dowels? I'm pretty confident that dowels would be as strong as, or stronger than, dominos, considering you could put multiple dowels in a joint the size you were using for testing.


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## copythat (Sep 28, 2016)

I've seen a similar video where the Kreg jig came out on top. Interesting.

Here is the video I mentioned above:


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## EarlS (Dec 21, 2011)

It looks like you didn't include the Leigh Mortise and Tenon jig. Any way you could blow up the text on the table?


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## Ted78 (Dec 3, 2012)

I'd be curious about dowels too. They seem to be used a lot in older factory made chairs, and they also seem to be a really common failure point. I cant' say if that's down to execution of the dowel joints or the quality of the glue, or maybe just dowels joints were so ubiquitous that dowel joints are what I see when furniture falls apart. In my experience pocket screw joints get loose over time and the joints gets wobbly, though fixing it for another decade or so only involves a minute to snug up the screws. I am curious but don't know if the screws back out or it the wood shrinks or compresses. Mortise and tenon seem to hold up extremely well as one might expect. I assume dominoes or floating tenons would hold up just as well, but not sure they have been around long enough (or at least commonly used until recently) to make a determination on their longevity.


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## RichT (Oct 14, 2016)

It's pretty obvious the OP has no interest in dialog regarding any of this. He clearly was using LJ simply as a means to boost his view count on YouTube.

I won't be falling for it again.


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## WoodWorkLIFE (Nov 3, 2016)

> It s pretty obvious the OP has no interest in dialog regarding any of this. He clearly was using LJ simply as a means to boost his view count on YouTube.
> 
> I won t be falling for it again.
> 
> - Rich


So a dude has to respond right away? I have a life and job and stuff you know, I monitor the conversation via email alerts then pick a time to come back an respond. Your comment made that time now, so I guess thanks for the nudge.


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## WoodWorkLIFE (Nov 3, 2016)

> Interesting video. I do question the validity of testing cantilever butt joints. Most assemblies are going to have joints on two ends of the rail or apron, so the load will put the joint in a shear mode, and not torqued like a cantilever (or are going to use a stronger joint like a half-lap or bridle). In your statement about a chair and the 400-plus pound load, the load needed to cause that joint to fail in a real situation, where the board is joined to the legs at each end, would far exceed 400 lbs because, again, the failure would be due to shear stress, and not torque. Even a biscuit would stand up to that because the long grain to long grain glue up inside the joint down the full length of the biscuit would be far stronger than torquing out the biscuit along the narrow face. Not that I d build a chair with biscuits however, just making a point.
> 
> When I do have a cantilever-type of load found in residential doors, where the hinge stile and rail joints are supporting the rest of the weight of the door, I use exclusively long tenons. I ve torn apart commercially made doors that used dowels, and I suppose they are adequate, and heard of people using dominos (though you d need the $1400 XL 700 to use the long dominos you d need for the job).
> 
> ...


I plan on doing a follow up video with joinery from the comments and dowels were #1 on everyone's mind. Regarding the cantilevered testing methodology, I agree with you it is not entirely real world as shearing is not the only way furniture can break. I used this technique to isolate the joint and get a consistent methodology that could be repeated if I ever wanted to. Building a whole chair proxy and adding load to it would have been a more accurate representation.

I tend to trust M&T like joints for load whenever possible and the proper amount of material removed from the mortise and left on the tenon will give you the optimal strength (without weakening the walls of the mortise and the base of the tenon.) The art of joinery, especially in a production or professional type application is what is the best cheapest (time is MUCH more expensive than tools) joint, that is strong enough for the task at hand. I suppose dowels will stand strong on this logic in the follow up, but I guess we will find out.

Someone once told me engineering is not making something as strong as possible, it is making something strong enough.


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## WoodWorkLIFE (Nov 3, 2016)

> I ve seen a similar video where the Kreg jig came out on top. Interesting.
> 
> Here is the video I mentioned above:
> 
> ...


Ya I have seen a lot of different shoot outs like this, pocket holes are usually up there as far as speed and strength. I think the splintery nature of this old fir played into the performance in this test. Maybe after I get through all of the joints I can revisit with different species of wood?


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## WoodWorkLIFE (Nov 3, 2016)

> It looks like you didn t include the Leigh Mortise and Tenon jig. Any way you could blow up the text on the table?
> 
> - EarlS


Leigh Mortise and Tenon Jig? I had never heard of it until just now. I will have to check it out, looks interesting. Might shave some time off the machine cut M&T without having to use multiple tools.

The chart is bigger in the article on my website, I was limited in what I could post on this site. 
 
Article on my Website


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## WoodWorkLIFE (Nov 3, 2016)

> I d be curious about dowels too. They seem to be used a lot in older factory made chairs, and they also seem to be a really common failure point. I cant say if that s down to execution of the dowel joints or the quality of the glue, or maybe just dowels joints were so ubiquitous that dowel joints are what I see when furniture falls apart. In my experience pocket screw joints get loose over time and the joints gets wobbly, though fixing it for another decade or so only involves a minute to snug up the screws. I am curious but don t know if the screws back out or it the wood shrinks or compresses. Mortise and tenon seem to hold up extremely well as one might expect. I assume dominoes or floating tenons would hold up just as well, but not sure they have been around long enough (or at least commonly used until recently) to make a determination on their longevity.
> 
> - Ted78


I have had so many pieces of cheap furniture joined with dowels fail catastrophically, I think it is due to the lack of surface area of the glue surface. I have also seen the dowels themselves fail over time, that is probably due to cheap woods used in some dowels. I am going to be looking at dowels in a follow up here pretty soon.


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## EarlS (Dec 21, 2011)

I, for one, would like to see what you come up with in your subsequent tests. I'm always interested in seeing how well the various "go-to" joints really perform in a direct comparison.


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## dhazelton (Feb 11, 2012)

I remember a woodworking magazine article pre-Festool days where a biscuit joint came out on top - the wood failed before the joint did. I've built screen doors out of 5/4 pine with a double biscuit at each joint and they hold up just fine.

I'll probably add a domino system - when Dewalt or Makita gets to make one.


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## WoodWorkLIFE (Nov 3, 2016)

> I, for one, would like to see what you come up with in your subsequent tests. I m always interested in seeing how well the various "go-to" joints really perform in a direct comparison.
> 
> - EarlS


What go-to joints do you have in mind? I was going to look at half laps, and maybe later lapped dovetails and other joints, but everyone has a different idea of what their go to joints are.


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## WoodWorkLIFE (Nov 3, 2016)

> I remember a woodworking magazine article pre-Festool days where a biscuit joint came out on top - the wood failed before the joint did. I ve built screen doors out of 5/4 pine with a double biscuit at each joint and they hold up just fine.
> 
> I ll probably add a domino system - when Dewalt or Makita gets to make one.
> 
> - dhazelton


I assume you meant Dowels and not biscuits? I have never seen anything say that biscuits are the strongest joints…

I will be interested to see how different companies get around that patents, one of the systems I am testing in the next video is the Rockler beadlock system, basically another floating tenon joint but using your drill instead of a dedicated tool.


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## dhazelton (Feb 11, 2012)

No, I meant biscuits - might have been Fine Woodworking back in the early to mid 90s.


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## a1Jim (Aug 9, 2008)

Fine woodworking had an article about the strongest type of joints called "Joinery torcher test" and as I recall saddle joinery and half lap joinery came out on top followed by loose tenon mortise and tenon joinery and standard integral M&T and the weakest joints were unreinforced Miters , butt joints, dowels, biscuits then pocket screws.
But now I see they have a new video about it.

http://www.finewoodworking.com/2009/02/25/joint-strength-test


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## NormG (Mar 5, 2010)

Thru tenons are awesome


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## wormil (Nov 19, 2011)

Strongest joint tests are fun but not particularly valuable. A wood joint doesn't need to be strong as possible only strong enough. Durability is far more important. Durability comes in 2 forms, a joint that is tough or a joint that is easily repaired.


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