Hide glue is the oldest and most traditional of all the glues used in woodworking. Hide glue has some good and bad features: on the minus side, it must be used hot, it can spoil; and cheap glue, unfortunately smells rather bad.
On the upside, Hide Glue's positive features are numerous: it is easily reversible; easy to repair; easy to sand; essentially non-toxic; the resulting joint will not creep; and best of all, it is transparent to most finishes, so you don't get visible glue blotches near a joint.
Hide glue is the traditional glue for veneering, and with a bit of practice you can successfully veneer without a pile of clamps or a vacuum press. It's the perfect glue for the occasional veneerer.
It's also great furniture glue. You can do many joints just by rubbing the wooden parts together until they get tacky and stick - no need for clamps.
Hide glue is sold in many different "gram strengths." The higher the gram strength, the tackier and stronger the glue. The stronger the glue is, the less "open time" you have between when the glue is applied and when it sets and immobilises the item being glued.
The Brooklyn Tool & Craft Hide Glue that we stock at Toolcraft is made by the last maker of hide glue in the USA. It's the highest refined hide glue available with the least amount of odour. We sell two different gram strengths:
The 192 Gram Strength is a good general purpose glue, and it's the least expensive hide glue around. That's why it's the most common. Its real application is veneering, although you can use it for regular gluing in a pinch. A lot of people consider it the best all-around glue for general woodworking (including veneering), because it also has the longest open time. If you are new to hide glue, this is the grade you should get.
The 251 Gram Strength glue is traditionally the most appropriate for regular cabinetwork. Its higher strength means that you can do rub joints more easily, and clamped joints will have less time to creep. But it's not optimal for veneering, when you'd want the maximal amount of time for squeezing out the excess glue.