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The label states that if it smells sweet then it's probably good, and if it smells sour use only as a household glue. I have some that I've had for close to a year, and to me it smells neither sweet or sour. I thought I'd do some tests, and if I get wood failure with or before glue failure it's probably ok. Any advice or thoughts will be appriciated:)

I've never had any turn on me, but I have always used it within a year or so.

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Waddy

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Sound Clips of most of my guitars

I'd test it out of curiosity, but I'd go ahead and relegate that bottle to household use no matter the results. Glue is pretty cheap.

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George :-)

After several months, the smell changes. That is not a myth, I osberved it myself. I'm not a chimist at all, but my logic says to me that if the smell changes, it probably means there's something wrong somewhere. I would just not take a chance. As it's been said, glue is pretty cheap, so why not always keeping your stock as fresh as possible. Same thing for shellac, by the way.

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Francis Richer, Montréal
Les Guitares F&M Guitars

Oh dang, I always thought it said if it tastes sweet...

I'll order a bottle to have the analytical lab at work see what this stuff is. If anyone is interested I will be happy to post the ASTM D905 shear strength results at room temperature and 150F using TB Original as a control.

My suspicion (since I have not yet tested it bear in my that I *am* speculating) is that LMI is selling a very cheap PVA with little or no biocides in the formula. Over time the adhesive will therefore literally spoil like a carton of milk and smell quite similar. However, strength is generally not effected, and historically our tests on spoiled products have found strength often increases! If anyone has a funky smelling bottle they would be willing to send me I will gladly reimburse you with two 16oz bottles of the Titebond product(s) of your choice.

Are there any other tests people around here would like to see?

Damping, Titebond vs hide glue!

Please!

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

My understanding is that the glue came from the book industry.

I've stopped buying products that are simply rebranded unless they tell me what the product is. This became a pet peeve of mine with StewMac's fretwire, made worse because they flat out refuse to tell you the tang thickness. It just confuses everything for no good reason.

I've been toying with testing dampening for a while, and it's going to require test fixtures and equipment that we don't have on hand... So it's more of a personal project that I'm less than confident that the company will be willing to fund. What I could do that would be nearly as valuable would involve laminating veneers, measuring their change in mass, and then measuring transverse and longitudinal modulus of elasticity. Our CTH room will take temperature and humidity variation out of the equation (the room itself is actually calibrated and maintains conditions within 1% RH and either 1 or 2°F.)

Sound reasonable? Any other suggestions?

Can you also test Gorilla Wood Glue White ? I understand that it is the same a LMI White - I want to know if that is a fact.

I have a bottle of Gorilla White - that is about a year old. I noticed lately is that it gels faster - a shorter set time. Stregth seems to remain ok.

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It's this new idea from recent decades that everyone gets a participation award. - MUX

Based on what I've heard about the LMI product, I do not believe it is related to gorilla's PVA wood glue. It's a ANSI/HPVA type II water resistant product, and LMI is clearly a uncatalyzed PVA that will readily dissolve in water when dry. I ran some competitive tests for a project a little over a month ago to evaluate its performance.

Results from ASTM D-905 Shear Strength Competitive Testing (Reported as Avg. ± 90% Confidence Interval):
Test articles were assembled from hard Maple, Acer Saccharum, and tested in a MTS Universal Tester with a 100kN load cell.

Titebond II
Room Temperature: 3922 ± 160 PSI
150°F Overnight: 1718 ± 110 PSI

Titebond III
Room Temperature: 3467 ± 280 PSI
150°F Overnight: 1295 ± 464 PSI

Elmer's Max
Room Temperature: 2255 ± 259 PSI
150°F Overnight: 1158 ± 52 PSI

Elmer's Carpenter's
Room Temperature: 3655 ± 530 PSI
150°F Overnight: 981 ± 300 PSI

Gorilla Glue
Room Temperature: 1263 ± 269 PSI
150°F Overnight: 698 ± 169 PSI

Gorilla Wood Glue
Room Temperature: 3393 ± 203 PSI
150°F Overnight: 1727 ± 173 PSI

I have not tested Gorilla Wood Glue's water resistance claim, but it is a well performing product from a strength perspective. Keep in mind that strength at elevated temperature correlates directly to creep resistance. Most people are unfamiliar with confidence intervals. They are a statistical calculation similar to margin of error. All of the values reported above therefore describe that the true value, lies within ± CI of the calculated average with 90% certainty. Due to wood variation, good test results typically have confidence intervals of ~20% the average.

Let me know if there are any questions.

"My suspicion is that LMI is pushing a very cheap PVA..."

Hugh,
Your expertise related to adhesives is of great value here on the forum and I do look forward to seeing the results of your tests. However, I will confess that your employment at Franklin Adhesives does make me wonder about possible prejudices within your research. If you wouldn't present "suspicions" or use words like "pushing" I would find it easier to accept your comments and any test data at face value.

Please understand that I'm just being candid about my own perceptions and hope that this will not deter your participation on the forum.

Best regards,

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George :-)

George,

I can certainly appreciate your concerns, and will try to address them here--

My posts on OLF are outside of my official capacity as a Technical Specialist at Franklin. I am exceptionally fortunate to be in a position that demands from me an absolute commitment to the pursuit of scientific truth. In no way is my work biased by marketing or sales, and it is expected of me (from the top) to provide accurate information and recommendations: even if that means referring customers to competitors or giving our marketing/sales group results that are inconvenient or they may not want to hear. In no way am I offended by your concern. If you have questions regarding test results, methods, data, etc. that would improve transparency just let me know.

With respect to my choice of words, since my posts are unofficial as far as Franklin and I are concerned, my language will at times be casual. My statement regarding LMI's product was speculative, and I have mentioned several times that I have not yet tested it. It is my best guess based on their own descriptions and my understanding of the formulation of adhesives. The rationale behind this is simply that I have a theory to present, and lacking empirical data, by prefacing it as a suspicion or hunch it will be more clear to readers that I have elected not to present it as fact. Perhaps I will edit my previous post to read "selling" rather than "pushing," although it's relatively minor IMO.

Again, I am always more than happy to provide transparency. Our technical group has an amazing amount of latitude and autonomy, for which we are extremely fortunate.

Sound good?

Hugh,

I can tell you that Taylor and Breedlove preferred Franklin Hi-Tack over Titebond. My understanding is that they come out of the same process and officially from Franklin the only difference is the addition pigment. This came from discussions with Taylor and Breedlove circa 1997. Nonetheless, they noticed a difference in strength and grab between the two.

My observations over the years is that LMI's glue dries harder and is more resistant to shrinkage, particularly on back seams which always sunk with Titebond.

Sounds good, Hugh. Thanks for taking the time to consider my comments and explain your thinking. I do appreciate it and hope to read more about your research and experience with adhesives (and other topics) in the future.

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George :-)

Thanks to everyone for their advice as well as the interesting discussion. I'm sure most on the forum look forward to any research posted by Mr. Evans or anyone else. Basic tests on the LMI white were good, it still seems to be quite strong, although I'll take the advice and use it for jigs or something other than structural components of the guitar. I use Lee Valley fish glue or epoxy for about everything anyway. And speaking of research in lutherie, there is an interesting article about R.M. Mottola and his research, methods, and opinions in the latest issue of American Lutherie, as well as a good review of Mr. Gore's books.

LMI white glue is made for them in small batches and is not rebranded from a glue maker or so they told me when I inquired about a year ago.

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http://goatrockukulele.com

Well, this testing will definitely be delayed for the time being as I was relieved of my position at Franklin yesterday in what amounted to a political hatchet job. So any further concern regarding bias can further be removed. I may still end up back at Franklin in a different division, but I'm considered all manner of options such as professionally consulting for guitar makers, or possibly take the plunge and giving full time guitar building a shot for myself (dream job.)

In the meantime, I will still be happy to lend my expertise because I really enjoy solving problems with luthiers. Anyone around central ohio interested in a consult or potentially a partner who could use some off hours shop time?

Sorry, Hugh. That's a blow to morale.

That's a sorry piece of news, Hugh. I wish you the best of luck in your search for a different position or new career path.

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George :-)