Fifty years ago was only 1960. Alternative glues to hide glue have been available since about 1900 (casein was developed about then, and urea formaldehyde sometime before 1940).
If the furniture was factory made after about 1910, it's unlikely you have hide glue. You can test it by heating the residue and see if it softens. If not, your best avenue is to remove as much of the glue residue as possible and use a modern glue.
[Urea formaldehyde glue will deteriorate over time and leave a surface that looks a lot like old hide glue.]
Last edited by Mike Henderson; 03-07-2010 at 03:56 AM.
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