Joint stress test

[David Klug]

Wood magazine has a vidieo showing how different joints hold up when tested for the strength of the joint. You can see it here

http://www.woodmagazine.com/wood/story.jhtml;jsessionid=HWLVNWSZPS3YPQFIBQPR42Q?sto ryid=/templatedata/wood/story/data/1158959100390.xml&catref=cat5610002

DK

[Larry James]

David,

Thanks for the video link. Very impressive considering that most furniture, face frames, etc. never experience the amount of force used in the tests. I'm sure purists will pick apart how the tests were conducted, and that other variables were not considered:rolleyes: . I'm impressed.

Larry

[Phil Thien]

I wonder why they didn't do a direct comparison between dowels and biscuits. Perhaps I have to read the article to find a comparison. But it would have been interesting to see it in the video.

I have a conspiracy theory: The biscuits didn't fair as well as they expected, and they didn't want to P-O a bunch of biscuit machine advertisers, so they burried the results.

[Ken Garlock]

The Cliff notes summary is:

1) Mortise & Tenon win all tests.:p

2) M&T with cross dowel pins are weaker than with out dowels.:o

3) Butt joints with dowels out perform pocket screws and biscuits.:D

4) Pocket screws out perform biscuits.:cool:

5) Biscuits are only slightly better than a straight butt joint.:eek:

[Mark Singer]

The Cliff notes summary is:

1) Mortise & Tenon win all tests.:p

2) M&T with cross dowel pins are weaker than with out dowels.:o

3) Butt joints with dowels out perform pocket screws and biscuits.:D

4) Pocket screws out perform biscuits.:cool:

5) Biscuits are only slightly better than a straight butt joint.:eek:

That was what my general intuition suggested....The traditional joints are best and well worth the time to learn!

[Mike Cutler]

Intersting. I wouldn't have expected an unpegged M&T joint do perform that well on the "pull test". It really says alot about modern adhesives also.

I'm not sure that I fully agree with their assesment of the pins in an M&T joint adding no benefit other than aesthetics. The pin is their to pull the joint tight,and mitigate loosening up down the line. I'll still pin M&T joints personally.