Open Glue Discussion

[rienk]

My understanding is the liquid stuff has food preservatives in it it to help the shelf life, and something similar to keep in in liquid. I have used more of it over the years than HHG. I have done some testing of my own and see no functional difference as far as actual holding power versus HHG. It steams apart about the same as well. But I caution that most of this experience has not been guitar related. I will be interested to see if it has the similar sonic conductance to HHG. It's also easy to test if it is stale, put a thin smear on a piece of paper and if it hasn't dried in about 20 minutes it is no good. That same test by the way can be used for shellac and I would imagine any other protein based substance we use.

The FWW article says that it has Urea in it to keep it emulsified.
Do you know what the typical shelf life is?
If it is virtually the same product as HHG (but in a more user friendly formula) then it is likely to be virtually the same tonally as well.

I buy CA by the quart, Titebond by the gallon, and resin by the drum... we use a lot of adhesives. But this type of stuff is new to me. And though I enjoy the learning process, I'm getting to the point where I'll just need to pull the trigger on something and see how it goes!

[B. Howard]

My understanding is the liquid stuff has food preservatives in it it to help the shelf life, and something similar to keep in in liquid. I have used more of it over the years than HHG. I have done some testing of my own and see no functional difference as far as actual holding power versus HHG. It steams apart about the same as well. But I caution that most of this experience has not been guitar related. I will be interested to see if it has the similar sonic conductance to HHG. It's also easy to test if it is stale, put a thin smear on a piece of paper and if it hasn't dried in about 20 minutes it is no good. That same test by the way can be used for shellac and I would imagine any other protein based substance we use.

The FWW article says that it has Urea in it to keep it emulsified.
Do you know what the typical shelf life is?
If it is virtually the same product as HHG (but in a more user friendly formula) then it is likely to be virtually the same tonally as well.

I buy CA by the quart, Titebond by the gallon, and resin by the drum... we use a lot of adhesives. But this type of stuff is new to me. And though I enjoy the learning process, I'm getting to the point where I'll just need to pull the trigger on something and see how it goes!

I have bought glues in similar quantities most of my life as well. All glues will start to degrade and suffer some diminished performance if they are not fresh. For guitar making I buy smaller quantities, generally only what I can use in less than 6 months. I have always bought the liquid hide at woodcraft, they turn it over pretty quick so I know it hasn't been sitting on a store shelf for a long time.

[justrfb]

Hello All.
Discussion like this just scares me to bits sometimes... For many reasons (ignorance, upbringing, economic, empirical data...) I am using plain old "Elmer's Carpenter's Wood Glue." I am being silly and half joking when I ask, "Is my guitar just going to explode under the string tension some day down the road?" I picture the glue in my guitar failing and the whole thing falling apart. Now I have been working with wood and glues for a long time and know enough that my thoughts are ridiculous, but sometimes... Also, does a guitar built with these special glues make it better than my guitar built with Elmer's?... Can someone tell the difference between the two playing them?... A question I didn't see asked or answered here, what glue does Martin use? When I was on the tour, to me they were using dark yellow wood glue, no? I am a little fish in a big pond here, could someone please just tell me my guitar will be fine. Maybe the next build I will use one of the other options. Thanks.

Sincerely,
Rich

[tippie53]

Elmers will also do the job. It is the same as tite bond.
The key to this discussion is that there are no sound scientific sound studies on the different glues. Lets face it , all the wood glues out there most likely will be string enough. It is the sound dampening quality of the glue and the effect on amplitude decay and such we want to see.
The initial study will be done with Tite bond and Fish glue just to see if these to different glue bases will have an appreciable effect on the amplitude and decay. Lets face it , there are many studies and lots of misinformation. I am suspect of glue information from the supplier , ASE ( American Society of Engineers ) web site has the best information as well as the government.
Brian Howard and I spoke last night and we want to do an initial study. The basic plan so far is to use the 2 glues but the test piece will be checking for a repeatable pattern of amplitude decay . We think we have the scope of the test plotted out for it to be a valid study. I will be speaking to an Acoustic engineer to see if he can add anything to the validity of the testing and data collection.
If anything we can either debunk or prove the argument.

[Darryl Young]

My thoughts when choosing a glue for instrument building:

- Creep resistance (over time will a glue yield letting parts under stress move?) Supposedly HHG and Fish are better at this than Titebond.

- Harness of cured glue (if it's soft it causes dampening.......supposedly HHG and Fish glue cure harder than Titebond.....and I believe it personally but is it enough matter?)

- Repairability (you can heat up HHG and Fish glue and reclamp without removing the parts and cleaning them (parts glued with Titebond must be seperated, cleaned, fresh glue added, and reclamped till dry which could be a big pain in the kester if it's a brace)

Another nice thing about HHG and fish glue is that is pulls the parts together while curing/drying. I assume this means it's volume shrinks slightly while drying, not sure.

I've have HHG on hand but I've not yet used it as I need to get a heater pot of some kind for it. I've used Fish Glue on my builds for all wood joints.

Strength of all these glues is probably a non-issue for me as they are all sufficiently strong.

[rienk]

Elmers will also do the job. It is the same as tite bond.
The key to this discussion is that there are no sound scientific sound studies on the different glues... It is the sound dampening quality of the glue and the effect on amplitude decay and such we want to see.
The initial study will be done with Tite bond and Fish glue just to see if these to different glue bases will have an appreciable effect on the amplitude and decay.
Brian Howard and I spoke last night and we want to do an initial study. The basic plan so far is to use the 2 glues but the test piece will be checking for a repeatable pattern of amplitude decay.

John, I would highly recommend expanding that list to at least also include Hide Glue - preferably both HHG and Liquid. Those four glues seem to be almost exclusively what 99.99% of all guitars are made of.
My suggestion is that, if you're going to go through the trouble, don't just do it half way.

I look forward to seeing the results.

[rienk]

BTW, here is a link that I found over on the AGB forum, from John Greven's website.
It's still just an opinion, but from someone who has been building and repairing guitars for 50 years, and has built 2,100 of them.

He is primarily addressing choices that Martin made regarding design and material changes, but there is an interesting take on HHG included.

http://www.grevenguitars.com/pdfs/MartinMyths.pdf

[tippie53]

This is an article with many opinions and few facts. I agree many decisions on Martin production were based on warranty issues. Again, the reason I want to do a true glue study is to find if different glues carry different tonal inference.
There are many myths about Martin and many opinions.
I don't want to add to the opinions. Please try to add true, factual information to the discussion.

[B. Howard]

John, I would highly recommend expanding that list to at least also include Hide Glue - preferably both HHG and Liquid. Those four glues seem to be almost exclusively what 99.99% of all guitars are made of.
My suggestion is that, if you're going to go through the trouble, don't just do it half way.

I look forward to seeing the results.

Our initial study will compare one PVA type glue to one protein glue. If there is no appreciable difference between these two vastly different types of glues I think it would be pretty safe to say that differences among protein glues, or vinyl glues for that matter, would be even smaller. Fish glue was chosen for it's ease of use and John has a lot of experience with the stuff, not to mention a good supply of fresh glue. All adhesives usded in the tests will be from the same bottles to minimize differences in batches. Our first round will be two different tests with two different parameters. One will be done under stress of string tension and the other will be done on a free plate. This will also allow us to see how the glue reacts sonically to stress. If these tests bear differences the scope may be expanded or new tests devised, this is just a starting point for what we hope to be a very scientific and useful series of tests.

[tippie53]

As Brian stated . if there is a significant difference at that point we will expand the study. Brian and I discussed this and we agree for the test to be scientific and accurate Brian and I can both to the same test . If the tests prove similar we have a valid outcome.