box joint testing

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Happened to come across this test of Joints, not all types but a few,...and
http://woodgears.ca/joint_strength/pockethole.html
Our friend has a couple videos on it, he found with the wood he was using that the pocket screws, even with glue, was about the weakest, other than a butt joint with clue.
Now I am not going to argue his methods of measuring since he did apply the same test to all, however in reviewing what he did and his points about pocket screws, I sort of think a shallower pocket, in conjunction with a slightly longer screw might help tremendously.
So I am tossing out that idea for your consideration.
I would ask him, since he has the gear set up for testing to verify it for curiosities sake, but then if he did so and it all worked out then he should be paid for the proof I would think.
In any event, I do not think you will find any pocket screws in my new wall cabinets for my kitchen. I wish he had tested with domino joints.
What does your experience tell us?
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On 12/18/2015 2:02 AM, OFWW wrote:

Hard to say here, I don't recall where the pocket hole joint method failed. Did the screws pull out of the mating side or did the end grain of the pocket hole piece fail. If the former, I agree with your thoughts. If the later, shallower pocket holes might be better. Anyway I typically glue pocket hole joints when I use them.

In my experience glued dowels and tenons and or floating tenons are better than screws.
But another black eye for TBIII. LOL
I have contacted Franklin more than a few times in the past 7+ years. My initial contact was to inquire on their position of the Wood Magazine glue test. Long story short TBIII did not do as well as TBII in the so called "Water Proof" testing. I did not recall the convoluted answer but they did send me a case of 4oz TBIII.
The a year or two back I learned that you must periodically shake TBIII to keep the ingredients thoroughly mixed. The agent that gives the glue a longer open time will settle to the bottom and if let to sit there for a long period will be extremely difficult to remix with out actually mixing, not shake.
There is also a shelf life on TBIII, and most bottles I see on the store shelves cut their recommended useful to 6 months or less.
And Now this test once again shows that the lesser yellow glue appears to provide a stronger bond than TBIII.
I think I am going back to TBII and or Elmers Probond or Gorilla White wood glue.
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Wow, that's worth knowing. I haven't used TBIII until recently, but there is a bottle in the shop now. Guess I should shake it every time I walk past.
I think as you suggest I'm going to stick with plain yellow glue (or epoxy if I need waterproof).
John
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On 12/18/2015 10:48 AM, John McCoy wrote:

John, I used to also buy TiteBond Extend by the gallon. Same problem. I would transfer to a smaller bottle and it came out like milk. It worked fine but it sure was thin. Half way through that gallon it thickened to almost a pudding consistency. Talking to Franklin I learned that I needed to stir from the beginning. Try doing that!
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On 12/18/15 1:13 PM, Leon wrote:

I got sick of dealing with that and now I just buy more, smaller, bottles instead of trying to save money by buying one big one. Not worth the PITA to deal with stirring all the time. I'm on my last gallon and it'll be my last.
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On 12/18/2015 1:33 PM, -MIKE- wrote:

Yes, I buy quarts now. BUT the regular TBI and TBII should not be a problem. It seems to be more with the longer extend times that present the short life shelf life.
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wrote:

this is all very interesting. As I am fixing to build 10 more beehives for spring at will amount to about 160 box joints that will need to be glued up. I find the results of TBIII compared to TBII or the elmers quite a surprise.
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On 12/18/2015 10:50 AM, Steve Barker wrote:

Shocking IMHO. FWIW the "Water Proof" classification on the TBIII bottle is deceiving. I looked that classification up and learned that no where in the description of the testing method did the words water proof show up except in the title of the classification. Only water resistance was used. Sounds like a good old boys agreement among those in that industry.
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wrote:

He did tests both with and without glue, very little difference, the glue let go first.
He did show the difference between screws both shallow and deep into the attached wood. Those that were deep, where you could almost see the tips, pulled the wood under the screw head free from the board with the pockets. If the screw was on the shallow side in the attached board then the board with the pocket was whole and the screw pulled out of the attached board. All material used was consistent on both sides.

His as well.

I used their stuff made specifically for melamine, didn't appear to hold or bond much better than TBII, without screws I wouldn't use either. Those shop cabinets are coming down after other projects are done, I'll use them for jigs.
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On 12/18/15 2:02 AM, OFWW wrote:

I've found that pocket screws are stronger in harder woods and yes, longer is better. All this, however, seems a bit too much like common sense to me. :-) I don't think I ever needed a test to tell me that a glued joint is going to be stronger that a pocket hole screw. Sorry, I don't mean to offend anyone, but that's always seemed like a "duh!" to me.
Here's my verdict and why I use pocket screws. They're strong enough. I use them for joints and applications in which they are strong enough or even stronger. You don't always need a mortice & tenon joint, nor a dovetail, nor a rabbet joint. You don't always need glue. Some times a pocket screw is good enough. Some times it's better than good enough. And you know what? Some times it's perfect for the job.
And I certainly didn't need to see a test to tell me two pocket screws in soft wood are much weaker than a glued M&T joint. :-)
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wrote:

Well I need to learn all I can, the glue verses screws test lost to the screws.
In pulling down cabinets in my kitchen I have been pulling them apart. They used dowels in the face frames with glue, after 40 years of sitting there the dowels mostly held strong, the glue and nail joints (or staples) were a mixed bag, it was surprising how much glue just gave up, where there was particle boards it was self destructing and stunk really bad.
Sometimes I wonder if it isn't just better all around to use horse glue, and epoxy for the tough stuff.

I'd like to see a test between the green machines M&T joint and a 3 dowel. Especially between a square tenon vs rounded with everything else being equal.
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On 12/18/15 1:09 PM, OFWW wrote:

IMO, it's the particle board that gave up. A glued particle board joint is only as good as the particle board, which we all know is about as strong as cheddar cheese. :-)

Epoxy on particle board is only as strong as the particle board, right?
But really, you already conducted the only *real world* test that has any relevance. You pulled down your cabinets and had to tear them apart, right? So glue, particle board, screws, staples, whatever combination of whatever they used worked for your cabinets. They didn't fall down, they had to be torn down.
Fast forward to today, however, and we've reached to tipping point. We have major cabinet manufacturers using a strange, soft, hot-glue mix on their cabinets and drawers in combination with long staples, and that $h!t's just falling apart en masse all over the place.
I may start a business that does nothing but repair and replace these crappy drawer fronts that are put together like this. I'm talking 1/2-3/4 million dollar homes using contractor grade cabinets built like this. It's disgusting... but lucrative.
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-MIKE- wrote:

To avoid issues like that, I think you might have to be your own contractor.
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On 12/18/15 1:45 PM, Bill wrote:

I'm not sure who misunderstood whom. :-) I'm saying I'll start a biz that goes around to these homes and repairs these crappy cabs. I'm already doing this with other things in this area. I make a decent amount of money fixing stuff that the original builders did poorly or outright wrong.
In many cases, the homes are still under warranty from the builder, but the homeowners are so sick and tired of getting the run-around, blame games, or having the same people who did the crappy work to begin with come back to do more crappy work to "repair" their previous crappy work.... that they would rather *pay me* a premium to fix it and do it right than get it done for *free* by the incompetent builders.
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-MIKE- wrote:

Yes, I understand. By the time they meet you they are disgusted. They thought they paid for quality the first time around!
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wrote:

Well, actually the shelves were cupped, on the wall units, one group of cabinets was sagging more and more, but the faces being oak were tough as nails, and the ends were Oak plywood and basically they were what was holding it all together. As you noted the particle board was all crap, crumbly, sagging and so on. And yes, the "real world test" was worth its weight in gold.
As a result I am wondering if 1/2" ply cabinet grade isn't just as good as 3/4" for my purposes, as 1/2" will support granite or whatever, and for shelving should last at least 50 years or until the next earthquake. :)

Seems like the cabinet doors are all stamped out like model A fenders around here, and they sell it as a kitchen upgrade using your existing cabinets. Found I make upgraded cabinets, increase the storage space by at least 1/2 and make it look really good for 1/2 the price of box store contractor upgraded doors alone. Give or take a little. Plus, for me it is fun.
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On 12/18/2015 1:31 PM, -MIKE- wrote:

Shhhhh....
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On 12/20/15 10:15 AM, Swingman wrote:

+1
I was talking to a GC around here who actually tries his best to do the highest quality work he can and cares about his clients and pleasing them.
He said the reason I'm seeing this so much is because the margins for a builder are often the same or less on a $650k home as they are on the $190k home. Both homes might be on 1/2-3/4 acre lots but the lot for the $650k home costs $350k and the house is expected to be 4x the size of the $190k house, have detailed trim-- chair, picture, 3 and 4 piece crown throughout-- recessed ceilings in almost every room, and a kitchen that looks like it's from the cover of a magazine, etc, etc. The man hours for building the bigger home are much greater, as well.
By the time the builder has done all this, he's set to make the same or less on the bigger house with the price tag 3.5x higher. He said this is why you get builders using particleboard cabinets in these giant homes because by the time you add up the hundred or more cabinets in these behemoth McMansions they can save $20k just by downgrading the cabinets.
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On Friday, December 18, 2015 at 11:10:06 AM UTC-8, OFWW wrote:

No, it won. A proper glue joint is NEVER end-grain to long-grain, so a right-angle joint, glued, to compare to a right-angle pocket screw joint, would be mortise/tenon or box joint. Those, because the strain is spread over large area, allow the glue to hold. A simple butt joint, or even a shelf poked into a dado, affords only endgrain-to-long-grain surfaces mating, and we've all disassembled that kind of joint. It comes apart easily.
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wrote:

LOL, Actually you are correct. I guess I got caught up in Matthias (sp) surprise that the glue joint failed so quickly, but you described it spot on, Thanks
Still, as you say, the other joints were clearly superior and the finger joints as well with glue. I love all this learning, never felt so stupid in all my life.
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