A few months back I was involved in a glue discussion at the OLF. More specifically the topic was about hot hide glue (HHG). Some issues had been raised about the difficult some users had encountered with short open time and storage with the glue stinking and going to liquid and, well you know the story.
Anyhow I had made comment that hide glue is quite simple to mix, use, and store but like anything it does have a learning curve and that most issues are easily dealt with if one simply takes the time to understand the product a little. This of course did not go down too well with some folks who immediately took my comments to be a personal attack upon their ability to understand simple things
. But that is the nature of internet forums, some more so than others it would seem. As that topic progressed, I went on to mention that I had in fact stored a bottle of hide glue in the fridge for over a year and that it had shown no sign whatsoever of developing an offensive odour or mold. I further explained that I had reheated that same bottle of glue on 'many' occasions, used it, and put it back in the fridge, and that contrary to the popular held belief suggesting that fresh batches of glue need to be mixed every few days for fear of spoiling, I remained confident enough that the effects of age and constant cycling from hot to cold had diminished that batch of glue's bond strength so marginally that I went on to use it to glue on a bridge, and that bridge had remained in place, and play, upon that guitar (The Matey) for over a year with no sign of lifting whatsoever.
Anyhow here is a copy of that post with an image I uploaded showing that bridge on the guitar. Yes it could be any bridge on any guitar but you will have to take my word that the glue was as old as I say when the bridge was glued on and that this is indeed an image of the same.
Here is a link to the entire thread if you would like a look:As you suspect, clean up is a matter of timing. Wait too long and it can be difficult to get off, too soon and it will smear. What you are looking for is firm gel, not just skinned over liquid, not leathery, but a firm gel. I use a chisel tipped stick and if your timing is right, the glue will just roll right off the wood so easy you will be done in a blink. It helps to dip the chisel tipped stick in the hot water of your glue pot now and then to freshen it up, wipe off the excess, and away you go.
I know lots of info is out there to say you should use distilled water or you should never heat more than 140f or you should mix this much glue with that much water etc, etc, etc but IMHO, and all of this is only my opinion so take from it what you will, that stuff is only a general guide at best and most has only come about to satisfy the modern need for people to know every specific detail before they get their hands dirty in the hope they will not need to find anything out for themselves. If you went back to 1930 and walked into a hardware store to by some HHG, at best the instructions would have read something like "1: Mix with water. 2: Heat until dissolved. 3: Apply glue as required and clamp."
Just remember, the glue has not changed since then so the same rules apply. In fact other than better purification, the glue has not changed much since the Egyptians used it well before there was a Fahrenheit or a thermometer. If you do not experiment and stick too close to a set of 'rules', you will miss out on one of the greatest benefits of the product, and that is it's flexibility in regards to the way it can be adjusted to best suit the task at hand. I have regularly heated hide glue well above 140f for repair work and made good strong glue joints with no discernible loss of strength. I have often added water to thin the glue for certain applications with no discernible loss in strength and have heated the same glue in the same bottle many times with it re-thickening to the point I have added water just to maintain what is my own preferred working viscosity which is akin to warmed honey.
I acknowledge there are opinions out there that point to studies and test which allegedly contradict what I say here about reheating, maximum heat and amount and type of water to use etc. I to have read that fooling with these things can affect the glues overall strength. In fact I will even concede that they are probably correct to a point. But IMO, if indeed these studies and opinions are correct, they are no more so than one who suggest that the horse that won by a nose, is faster than the one who ran second. Yes one was indeed faster but 'both' still ran the course on the day and within a few seconds of each other and we are only trying to achieve a good strong glue joint, not win any race.. And remember this, no matter which horse won on the day, they will both end up glue in the long run, and when that happens they will be chopped up and their relevant bits will be 'BOILED' in a big pot at a temp well over 140f until all the collagen has been rendered from them.
I am not saying here that you can just boil the crap out of your glue and not ruin it, and I am not saying that you can water it down to soup without loss of strength either, but with a bit of common sense and working within reason then there is a lot more scope to this wonderful product than first 'meats' the rib-eye.
Here is some research of my own. I made a batch of HHG in early February 2008, I used plain tap water. I built a guitar and completed all sorts repaired with the same batch of glue making adjustments of water as required. After each session, the glue was stored in the fridge, not the freezer, the fridge. I then glued this bridge on to a restoration with that same batch of glue around June 2009 and after 11 month of being strung to full pitch and played daily it has not budged and I remain confident that it won't. The last bit of that batch is still in my fridge and in a pinch I would use it again and just might to prove a point because after more than 2 years it is still firm and clear, does not smell, and there is no sign of any mold or other macrobiotic activity to the naked eye.
Anyhow Gabe I am certain that if you persevere you will be richly rewarded for you efforts. It's not so much about the science than it is the feel, so grab your year old batch, divide it up, and start experimenting with heat and water and measuring the run from the stick by eye for viscosity. You don't need scales or a thermometer however I do have a pin point on the body of my warmer to indicate 140 -145f for general use and if I need it hotter I just turn it up a bit. Do some test joints and then some failure experiments. Examine if when torn apart in 24hours the joint has wood from it's mating component still attached, if it does then you know the glue is as strong as it needs to be for anything.
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Cheers
Kim
http://www.luthiersforum.com/forum/view ... &sk=t&sd=a
And now for some follow up:
The batch of hide glue in question was first mixed in January 2008. The bridge in the above image was then glued on to the guitar using that same batch sometime in June 2009, which was 17 month later. So here we are today, just over 16 month down the track and now that original batch of glue has reach a fully matured vintage of some '33 months old'. It is still clear, and it smells quite fresh. In fact, as you can see for yourself, it just looks like a nice clear golden jelly in the bottom of the bottle (not much left though).
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I took two lengths of radiata pine, old dry wood salvaged from a single bed that lay in pieces on a kerb side dump day. It is destined to be ripped into stickers for wood storage but was diverted for use in this experiment first. Each bit of pine was 700mm (28") long x 90mm (3 1/2") wide x 35mm (1 3/8") thick and each board was run through the thickness sander to be cleaned up with 80 grit abrasive ready for gluing.
One end of each board was then marked at 100mm (4") forming an indicator for the glue spread area to create a simple face to face glue joint. The 33 month old hide glue was then heated and applied liberally to just one of the marked surfaces. The joint was then bought together, slipped a little to even the spread, and clamped securely to cure.
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So, whats is the point of this thread? Am I telling you that 'you' should use hide glue over all others?? No not at all, you can use what ever you like as far as I am concerned and most wood glues will work just fine in lutherie. My point is that I have read very much bullshit on the internet about hide glue over the years and the truth is that most of this bullshit is propagated by those who lack the patience to come to terms with what is essentially a 'very' simple and effective product. It must come from the instant gratification factor that is so much a part of today's life, because it seems to me that so many things get a bad wrap from the novice who simply can't come to terms with the fact that 'they' got it wrong. So rather than persevere, they simply place blame elsewhere and move on to "easier" solutions.
This does not just stop with glue, it goes for any number of processes from resawing to finishing and every step between and everywhere you look on the internet you will see it, "tried it and did not work", "too hard", "bad concept", and who is this advice coming from? My guess is that it is not coming from those with the perseverance to learn and develop the required skill to achieve success with the given product or method, and most times that is all skill really is, the reward of perseverance.
Cheers
Kim
Everything okay at home Kim? 
