I'm about 650 instruments into building at this point, about 2/3 ukes and 1/3 guitars, and still puzzle over the visible Titebond glue creep, or swelling, or whatever it is on the top and or back joints. Although I don't get to see many of my instruments again once they leave my shop, I think that glue creep shows up fairly soon on some of them. It makes a visible , but not tactile noticeable, unevenness of the joint. I've always used Titebond for all joints. I have no problem with how it works on any other joint besides the top and back. Recently I was reading Romanillos's latest book , with whom I studied with 15 years ago and greatly respect. On page 34 of Making the Spanish Guitar he says that he has seen the the same thing and that he finds it" aesthetically unpleasing". Those are my sentiments exactly. I have never witnessed a glue failure on those joints using Titebond, and I trust it, but the look basically sucks! I have hesitated to try other glues, precisely being concerned about glue failure in the high heat and humidity conditions that I live in in Hawaii. My shop is dehumidified day and night, but the instruments can be subjected to a wide range of climates once they leave my shop. Actually very few of them stay here in Hawaii, but still I'm concerned about humidity elsewhere. I don't really see any other glues that I might want to try other than hot hide glue. Because I'm only considering using it on a couple of joints, I can't see having a $100.00+ glue pot sitting on my bench unless I'm pretty sure it is the answer to my problem. On the web I find scientific test results that indicate hot hide glue actually resists heat better than Titebond. That's good. However, probably just because I've used Titebond for over 40 years I'm still resistant to change. I am also wondering why I don't see more of the glue creep problem in factory made instruments. I've got finely planed glue surfaces and tight fits, so that can't be the problem, Anyway, I'm interested in responses that relate to the use of hot hide glue on the top and back joints. Thanks, Bob
Bob, There are some folks that use a small cheap ($20-ish) crock pot and a thermometer. That would be cheap way to check it out. HHG is very useful stuff to have on hand. I like the fact that it grabs fast, pulls together parts, and does not stain wood.
Thomas, Thanks. I know about the alternative warmers like crock pots, baby bottle warmers etc. This is a situation where I can't really experiment with the variables. Wish I had the time to make some instruments, string them up, and let them sit for a few months to check them out. However, what I make is generally sold so I need to be reasonably confident that changes I make will work out. I'll be more comfortable just having a warmer that does it's job without me having to monitor it. This is a case where getting the task done right is far more important than the $.--Bob
I understand Bob. I have a Hold Heet I bought on eBay. I still keep a candy thermometer in it for insurance.
The need for monitoring glue temperature is VASTLY overstated by most of our community. The industrial recommendation is not to exceed 145 degrees or so, but that presumes the glue will be under heat for a full shift at least. Degradation takes place as a function of time and heat, so for our purposes, we can be pretty sloppy about heat if we don't keep it cooking all day long. Me, I don't worry about it at all because I use a microwave to heat it directly from the refrigerated gel state and use it immediately, so if it boils there's no danger at all of any compromise.
My old pals, Hideo Kamimoto and Mario Martello both made lifetime careers of instrument repair using hot hide glue and both claimed they'd never heard of any danger in overheating the glue. Both use a simple hotplate and had a pan of water with a small jar of glue floating in it. They never used a thermometer and both said all they did was watch to see the glue itself didn't boil, but that the water always had tiny bubbles coming up.
As to clamping time, I believe the need for longer time is greater with underclamped and poorly fitted joints, where there might be somewhat more water to evaporate or be absorbed into the wood. I leave everything overnight because it's convenient to do so.
Remember that hide glue was and is used by folks with nearly no resource or equipment, and it has worked well for many centuries.
Our friend, Flip Scipio, worked at Guild years ago and said that the hide glue pot was handled exactly the way Chester maintained his coffee pot on Gunsmoke.** Add more when it gets low, add water if it gets thick, never clean out the pot, use it when it looks like tar - you know, that kind of thing.
** OK, for those too young to have been acquainted with Gunsmoke in the 1950s, here's how chester described making coffee:
"Most people just don't know how to make good coffee. In the first place, they boil the water before they put the coffee in. Any fool knows you gotta put the coffee in the cold water and bring them both to a boil together. That way you get all of the flavor. Worst thing they do, they throw away the old grounds after using them once. What they don't know is that they are throwing away the best part. You got to keep them old grounds and you add alittle fresh coffee every morning and let her boil. Shoot, you don't make a cup, you build a pot. You don't really get a good pot until you've been usin' it about a week. Then it's coffee!"
Frank-Thanks for taking the time to respond. I think I'm getting the picture finally. Looks like a case of "don't sweat the small stuff". I'll just dive in and see what happens.--Bob
Short answer on Titebond v HHG: As a manufacturer I don't have this problem with Titebond original even with some of the thin mahogany we center join. Occasionally I will see a joint evident but as we hold our bodies and necks for a while before using them and do a final finish and flatten just before build any un-eveness around joints is taken care off in the pre prep QA.
Titebond, like many other glues needs to settle and normalise the local moisture content in the join area so a glue up and re-finish in the same week is going to leave some witness lines from time to time. Headstock reconstructions in our repair area are a case in point where deep cracks take a while to harden up and require resanding a week or so down track to knock off the glue ridge that forms, or even out ares where the joint has sucked in.
These days I'm ambivalent to the various discussions on glue types as I have no problems with Titebond. However, I would have no problems (apart from using dead animal products) with HHG either if I chose to use it for whatever reason. The management and execution of the glue up and the quality control from start to finish is what makes for a successful procedure.
HHG in wide temperature extremes will suffer a range of problems but no more so that Titebond, except the problems will be different. Test both glues in your operating environment and pick the one that works best for you and your procedures.
Russell, I'm not a manufacturer, but have been a full time acoustic instrument maker for over 40 years, www.pegasusguitars.com . Never had to work for anyone else luckily. A lot of people seem to know what I'm talking about on glue creep on 2mm thick joints and a lot say they have never seen it. I know I'm not the only one who sees it. That said, I don't have a clue as to what the actual cause is, I only know I don't like it. I get the dead animal part too, as I have been a no animal vegetarian since 1971. That is part of the equation in my HHG considerations. I control my shop humidity 24 hours a day, the wood is dry, I never even come close to glue up and finish in the same week (how is that even possible?), the joints are hand planed clean and true, the glue is not old, and I never swear during glue up. That comes months later, when and if I ever see glue creep. With this whole glue question I am just on the path looking for the right direction.--Bob
The problem with opining here is that Hawaii (and I've done time there) is a way different place than my own Mediterranean environment and it's a pretty brave call to try and make a diagnosis when combined with different timbers, techniques and clamping and RH etc. Which is why I'm not too emphatic these days: HHG has very little creep (although I'm not sure that creep is the problem here) so it's probably a good place to start looking if the Titebond problems persist. One thing that we do is to apply maximum pressure in glueups via jigged clamping, this seems to make for better joints in most grained timbers.
"glue up and finish in the same week (how is that even possible?)" Our semi hollows can be put together in a couple of days and the first lacquer can be shot as soon as the wood filler dries, if we wanted to, but as I say, I like to let them cycle and de-stress before final flat and finish. Takes about 30 hours (aggregated) to go from billet to completed unit if it was a question of manhours per guitar. But I still like to waste a half a day on fret ends and fingerboard edges etc. Old fashioned I guess.
Maybe just follow the bouncing ball with some of the expert dudes here and see how it goes - these guys are encyclopedic and dead set when it comes to the finer points of HHG and similar sticky subjects. Good luck comrade,
Yep, environments, clamping, wood types, or even different characteristics of various pieces from the same species, and some say spiritual guidance for which I'm not inclined to spring for , are all factors for some in some instances. To wrap up my part of this quest for now, I ordered the glue pot and warmer sold on Amazon just now. I'm hoping Romanillos was right, which started me on this in the first place. Thanks for all the input. It was fun finding this forum anyway. I don't do much web searching on forums, but this one seems to be more intelligent than some. Enjoy your building.--Bob
I've been using the Lee Valley setup for repairs for about 2 months. I can't think of a single bad thing to say about it. After reading that furniture manufacturers used to pre heat parts and keep the assembly room at 120f, I was inspired to move the radiant heater from my garage to the basement shop. In the winter this heater takes the edge off of minus 30. In the basement mounted directly over one of my benches, it brings the temperature in the benchtop area, to the 80 to 90f range in about ten minutes. I'm hoping it extends the open time and promotes weight loss simultaneously.
I found this interesting Thanks John.