FWW Article: "you can't be serious" abount clamping.

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wrote:

Complete with toes that hang straight down over a sawhorse lip? <G>
<
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On Fri, 05 Oct 2007 06:43:05 -0400, C & S wrote:

Between that and the recent bandsaw fiasco, Fine WW may soon become "Final".
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C & S wrote:

Franklin recommends 175-250psi for Titebond III on hardwoods.
I know a local maker of bass guitars that uses a 20-ton steel press for gluing up laminated body blanks. He uses custom-made 1-inch thick steel plates top and bottom because weaker materials kept bending.
Of course you can get very acceptable joints with much less pressure than this, especially if your mating surfaces are well machined and in good condition.
Chris
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But how much pressure is it, really? 20 tons spread over one square foot is 277 lbs/sq. inch.
- Owen -
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<snip>

This is what happens when you let journalists pretend to be experts. It also happened to American Woodworker when Reader's Digest took over. Out with all the old experts and in with a bunch of journalists. The difference with FWW is that it's been happening slowly, over a long period of time (since the early 90's). It happened all at once with AW. None of the magazines want real (educated) technical expertise - not even if it is offered for free. I'm sure the journalists are making that call too. You can expect this to continue until one magazine suddenly realizes that they can make money by providing correct, technically accurate, useful info.
I registered on the Taunton web site so that I could read their forums. BIG mistake. Now I get spam from them every day. I think I've seen 200-300 "Last chance for free shipping" messages (how many "last" chances can one get?). So, I guess the MBAs have taken over the marketing department too.
Ed Bennett snipped-for-privacy@ts-aligner.com
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Ed Bennett wrote:

...
Well, in this case the author is actually a PhD in Industrial Technology specializing in furniture manufacturing technology it appears. See my earlier response.
It appears there is some actual basis for the claims made, what isn't possible to determine from the article is the applicability of the research to the task at hand...
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"dpb" wrote

While the OP doesn't say what type of glue the article references, it makes you wonder how many thousands of pounds/sq in clamping force Stradivarius used on those violins still being played? :)
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Swingman wrote:

What the article says is "I'll assume you're using yellow (polyvinyl acetate--PVA) glue..."
The tome I posted previously that reference one of the good doctor's published papers used PVAc and U-F according to the abstract I was able to find.
Well, of course ol' Strad had the advantage of dividing by a small denominator to raise the pressure significantly... :)
Although, had they even invented pressure back then? <vbg>
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"dpb" wrote in message

I'm often convinced it was invented strictly for my benefit ... parental, marital and financial.
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Didn't see this before I posted. If I get a chance I'll check out the FWW article. I haven't received FWW since 1992 so I will have to wait for it to hit the newsstands.

Based on the references you posted above, it would seem that they erred in the opposite direction this time: too academic.
Ed Bennett snipped-for-privacy@ts-aligner.com
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Ed Bennett wrote:

Except they left every bit of the basis for the recommendation out of the article as well as any discussion of difference in results in not following the recommendation (which of course there's a tremendous amount of data that says gluelines don't fail at far lower clamping pressures).
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Turns out the "journalist" in this case is a University professor with several publications on the topic of glueline strength in wood.
While one may disagree with his results, I'd argue that he is an 'expert'.
scott
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Scott Lurndal wrote:

His results are probably "spot on" for what he tested, but it's the applicability and usefulness for the intended audience I question... :)
In particular, notice in the abstract of the paper I posted earlier the testing was for shear strength of the joint which is rarely the failure mode in most furniture glue joints. It also neglects that most well-fitting joints in testing through the years at much lower clamping pressures will break the wood rather than the glue joint. Once the joint is as strong or stronger than the wood, there's very little if any point in worrying about making it stronger. In short, the results may have some limited applicability for commercial manufacturing processes for which I strongly suspect the research was directed, but think it of little practical value for the average guy reading FWW.
None of this directed at you, just one last thought I had on the overall subject and this seemed convenient place to put it in...
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on 10/5/2007 8:18 PM Scott Lurndal said the following:

Timothy Leary had a PHD in psychology.
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Bill
In Hamptonburgh, NY
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And he was an expert on LSD.
scott (pun intended)
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and Jesus was a Rabbi.
not exactly what we'd call orthodox today, but a Rabbi nonetheless.
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wrote:

In some ways he studied it well. <G>
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Timothy Learys dead. No, no, no, no, hes outside looking in. Timothy Learys dead. No, no, no, no, hes outside looking in. Hell fly his astral plane, Takes you trips around the bay, Brings you back the same day, Timothy Leary. Timothy Leary.
Timothy Learys dead. No, no, no, no, hes outside looking in. Timothy Learys dead. No, no, no, no, hes outside looking in. Hell fly his astral plane, Takes you trips around the bay, Brings you back the same day, Timothy Leary. Timothy Leary.
Along the coast youll hear them boast About a light they say that shines so clear. So raise your glass, well drink a toast To the little man who sells you thrills along the pier.
Hell take you up, hell bring you down, Hell plant your feet back firmly on the ground. He flies so high, he swoops so low, He knows exactly which way hes gonna go. Timothy Leary. Timothy Leary.
Hell take you up, hell bring you down, Hell plant your feet back on the ground. Hell fly so high, hell swoop so low. Timothy Leary.
Hell fly his astral plane. Hell take you trips around the bay. Hell bring you back the same day. Timothy Leary. Timothy Leary. Timothy Leary. Timothy Leary. Timothy Leary.
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And he's _still_ spaced out.
scott
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On Oct 5, 6:18 pm, snipped-for-privacy@slp53.sl.home (Scott Lurndal) wrote:

Indeed. I didn't see that tidbit until after posting. I still maintain that it was the journalist types who decided that he was the right guy for the article. It's kind of like hiring a Phd in electormagnetic wave propagation to tell you what's on TV tonight.
I've talked to several of these magazine editors about the lack of any technical expertise on their staffs. I've suggested that they need someone who is familiar with basic experimental design and data collection. They just don't understand why. It doesn't take a Phd, just someone who has taken some undergrad experimental science courses. The "Myth Busters" guys, while not always designing perfect experiments, consistently do better than anything I've seen in the woodworking magazines. And, they don't mind doing more experiments when someone pokes holes in the results (as opposed to the "we stand by our results" BS).
Ed Bennett snipped-for-privacy@ts-aligner.com
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