Speaking of being green...
None of my techniques are green for the sake of being green. Most are "green" quite by accident. I choose my materials and techniques based on what I feel are best. What makes them best is probably more subjective than I care to admit.
Some are not, however, subjective. Case in point is my choice of glue. My glue choice is non-toxic, renewable, non-polluting and stronger than its toxic, non-renewable, polluting counterparts.
My glue is C(102)H(151)O(39)N(31). That looks pretty scary. It is the oldest form of glue known to man. A mural showing it being used first appeared in about 1500 BC by Thutmose III. King Tutankhamen's casket was glued together with this stuff in 1350 BC.
This amazing stuff is made from cattle hide, trimmings from a leather factory. Boiled until the collagen is released, then dried and packaged. I reconstitute it by adding water and heating it to 140 degrees Fahrenheit.
It is hygroscopic, as is wood, so it changes with the humidity in the air, just like the wood it is securing. It does not affect finishes. Most glues cause blotching of the finish if it is not completely removed from the surface of the piece.
The biggest advantage is that joints held by it can be repaired. By applying heat and moisture (steam?) the glue joint can be reversed. It seems pretty important to me that you are able to repair a piece rather than disposing and purchasing a replacement.
Hide glue is another of those old techniques/materials/skills...that are nearly lost.
If you are interested in Hide Glue, the book "Hide Glue" by Stephen A. Shepard or Stephen's blog at http://www.fullchisel.com/ are highly recommended.
Coming up: Finishing with wax, milk and pill coatings!?!?!
W. C. "Bill" Sias, Joiner and Cabinetmaker.
My violin's fingerboard fell off many years ago and my grandfather glued it back on with wood glue instead of a water-soluble glue like they would have at the repair shop. Because of this, the fingerboard is off-set but unchangeable and the neck is somewhat compromised and therefore tone is somewhat compromised. I was wondering if there is any way you might know about to remove the fingerboard and get the wood glue off without damaging the instrument?
ReplyDeleteThere are several problems with acoustic instruments and modern wood glue. The first is that modern wood glue, when fresh out of the bottle, acts like a lubricant. Second, modern wood glue has an unfortunate property called "creep."
ReplyDeleteThe connection between your violin's neck and the fingerboard is essentially a butt joint. Glue is spread thinly on the top of your maple neck and the bottom of the ebony fingerboard. The two are introduced and then made to stay together until the glue dries. When I was building guitars I would secure the fingerboard to the neck with clear plastic packing tape stretched tightly until it was positioned correctly. Then I would use layers of sandbags to apply pressure to the joint until it was cured.
Your grandfather probably had trouble getting the clamps in place due to the lubricating effect of the glue and then when he got them on the joint experienced creep. Leaving you a worse repair than you had in the first place, one that few luthiers want to get involved in.
The repair requires that the two pieces are separated. Both cleaned of all remnants of the modern wood glue. Then gluing the fingerboard back on the neck with the correct glue, a high gram strength hide glue.
Separating the neck and fingerboard without removing other pieces is the hard part. You can't use steam in fear of the other parts being compromised.
The technique involves syringes, vinegar, alcohol and water.
I can't get to it until January but lets talk soon about it in person.
So, do you always use hide glue in every glue-up scenario, or are there times when you want to or need to use a modern glue?
ReplyDeleteI do use modern glues for outdoor furniture. Modern water proof glues out perform hide glue in water resistance.
ReplyDeleteHide glue's biggest advantage is the fact that it is reversible. I will use modern glue for a joint that I don't think will be worth the effort to repair. For example, a table top made of multiple boards, I suspect that if that were to fail the table would not be worth repairing since glue is actually stronger than the wood it joins.