Since 1868, Milligan & Higgins has been supplying natural
collagen-protein-derived products, e.g. hide glue, to industry.
If you need large quantities, e.g. 100 pound bags, they are an
excellent source.

The grade (strength) of hide glue is specified in "Jelly Grams."
Milligan & Higgins offers hide glue in grades 80 to 512.  The higher
the number, the stronger the cured glue (this does not imply better
adhesion properties to wood, cloth, leather, etc. and actually might
imply the opposite), but the shorter the working or gel time.

Typically, the range used for woodworking is grades 135 to 251, with
grade 192 High Clarity (water-clear when mixed) the most commonly used.
I believe that, for general mechanical musical instrument restoration,
the range thought to be best is grades 135 to 192.

I have heard that Milligan & Higgins "2X-High Clarity", which according
to Milligan & Higgins is Grade 251, has been used successfully in
mechanical musical instrument restoration.  Grades above 315 have often
been termed "too strong for woodworking."

  Milligan & Higgins
  P.O. Box 506
  Johnstown, NY 12095-0506
  Phone: 518-762-4638
  http://www.milligan1868.com/

Joe Orens