This type of video is right up my alley. I like testing that has
measureable results, and in this they even spend a couple of minutes
on the biscuit.
After watching though, it looks like I may have to buy a new doweling
jig!
And I knew the mortise and tenon was strong, but not that strong. I
would certainly think at least some credit would go to today's
adhesives. I think this video ties in well to an earlier thread where
there was concern about using glue only in construction.
http://tinyurl.com/yto5av
I am sorry I missed the magazine when it came out.
Robert
On Mar 21, 2:59 pm, "[email protected]" <[email protected]>
wrote:
> This type of video is right up my alley. I like testing that has
> measureable results, and in this they even spend a couple of minutes
> on the biscuit.
>
> After watching though, it looks like I may have to buy a new doweling
> jig!
>
> And I knew the mortise and tenon was strong, but not that strong. I
> would certainly think at least some credit would go to today's
> adhesives. I think this video ties in well to an earlier thread where
> there was concern about using glue only in construction.
>
> http://tinyurl.com/yto5av
>
> I am sorry I missed the magazine when it came out.
Interesting link. I could watch stuff like that all day.
The tests were setup a bit oddly. The force in the "shear" test is
being applied at some distance from the actual joint, so it is not
really a shear test, so much as a test in bending. They also test a
dado as in a shelf connection, then follow it with a face frame test.
That's misleading and the numbers have nothing to do with one
another. The face frame joints tested in the "shear" test are very
strongly influenced by the moment. In other words, the distance
between dowels would have a large effect on the joint strength, and
that skews the results making it difficult to really compare two
different types of joints. I know that real life forces are rarely
entirely shear or entirely bending moments, but the forces are
limited. A shelf or face frame rail presumably has a connection at
either end, which would limit the amount of bending stress the joint
itself would experience.
I'm surprised that they didn't make the test pieces more accurately
model real world stresses so that the test result numbers could be
applied to something. I already know a mortise and tenon is the
strongest joint, but how much stronger than another type of joint in
the same construction is the question The tests should have been
conducted on face frame mockups and shelf mockups and not isolated
joints. I'd hope the complete sequence of testing would have more
comparable results.
Still, interesting stuff to watch. Thanks for posting the link.
R
On Mar 21, 2:59 pm, "[email protected]" <[email protected]>
wrote:
> This type of video is right up my alley. I like testing that has
> measureable results, and in this they even spend a couple of minutes
> on the biscuit.
>
> After watching though, it looks like I may have to buy a new doweling
> jig!
>
> And I knew the mortise and tenon was strong, but not that strong. I
> would certainly think at least some credit would go to today's
> adhesives. I think this video ties in well to an earlier thread where
> there was concern about using glue only in construction.
>
> http://tinyurl.com/yto5av
>
> I am sorry I missed the magazine when it came out.
>
> Robert
This brings back memories. I did a lot of testing, under controlled
conditions, of corner joints in box manufacturing. My interest was in
how one vibrating side transferred energy to an adjacent side in a
loudspeaker enclosure. The amount of flexing that goes on, as captured
by high-speed strobe and camera combos is fascinating. So was this
video. We never tested for ultimate strength.
I love stuff like that. All it needs is Scarlet Johannson to do the
show and tell.
>From a scientific/engineering standpoint, the tests were somewhat
limited by scope. 20 batches of oak, 20 maple and 20 hickory joints,
then average them all. That would give us a somewhat better feel for
the joint itself, not the limitation of the wood used. Oak likes to
split, maple not so much...etc.
Thanks for that, Robert.
r
On Mar 24, 11:21 pm, Lew Hodgett <[email protected]> wrote:
> Robatoy wrote:
> > This brings back memories. I did a lot of testing, under controlled
> > conditions, of corner joints in box manufacturing. My interest was in
> > how one vibrating side transferred energy to an adjacent side in a
> > loudspeaker enclosure. The amount of flexing that goes on, as captured
> > by high-speed strobe and camera combos is fascinating. So was this
> > video. We never tested for ultimate strength.
>
> Set a strobe at about 6-8 Hz in a dark room and watch out.
>
> Brain goes into resonance if you stick around too long.
>
...some people may argue that something like that already happened to
me...
"RicodJour" <[email protected]> wrote in message
news:[email protected]...
> The tests were setup a bit oddly. The force in the "shear" test is
> being applied at some distance from the actual joint, so it is not
> really a shear test, so much as a test in bending.
Do you have any opinions about the test result posted at
http://www.dowelmax.com/test_results.htm?
Its obviously a singular test aimed at showing the dowel joint compares
favorably to mortise and tenon. I have yet to see any test or claim to say
that there is any joint stronger than M&T, but many applications are served
well with something easier than a traditional M&T joint. I am a very big
fan of the dowelmax jig. My pocket hole jig and biscuit joiner are gathering
dust since I got it. Of course, I don't need production speed/efficiency
either.
Bob
On 21 Mar 2007 11:59:36 -0700, "[email protected]"
<[email protected]> wrote:
>This type of video is right up my alley. I like testing that has
>measureable results, and in this they even spend a couple of minutes
>on the biscuit.
>
>After watching though, it looks like I may have to buy a new doweling
>jig!
>
>And I knew the mortise and tenon was strong, but not that strong. I
>would certainly think at least some credit would go to today's
>adhesives. I think this video ties in well to an earlier thread where
>there was concern about using glue only in construction.
>
> http://tinyurl.com/yto5av
>
>I am sorry I missed the magazine when it came out.
>
>Robert
That was a pretty impressive video. Thanks for the link. I'm curious
how dovetail joinery would compare.
Robatoy wrote:
> This brings back memories. I did a lot of testing, under controlled
> conditions, of corner joints in box manufacturing. My interest was in
> how one vibrating side transferred energy to an adjacent side in a
> loudspeaker enclosure. The amount of flexing that goes on, as captured
> by high-speed strobe and camera combos is fascinating. So was this
> video. We never tested for ultimate strength.
Set a strobe at about 6-8 Hz in a dark room and watch out.
Brain goes into resonance if you stick around too long.
Lew