DRY MIX RATIO/DENSITY OF HIDE GLUE
Some practical hints and helps:
The following weights and measures are approximate and intended to give some basic guidelines for preparing hide glue without using sophisticated equipment.
1 cup of dry glue weighs 5 ½ ounces (155-160 grams)
¾ cup of water weighs 5 ½ ounces
2 ½ tablespoons of Urea Prills weighs 1 ounce
1 ½ tablespoons of salt weighs 1 ounce
To prepare various glue solutions use:
1 cup glue to ¾ cup water for 1 – 1.
1 cup glue to 1 cup water for 1 – 1 ½
1 cup glue to 1 1/3 cup water for 1 – 2
To extend the open time (tack life) of the 1 – 1 mix, add ½ – 1 teaspoons of urea or salt. Use a little less for the 1 – 1 ½ and 1 – 2 mixes.
To make liquid (room temperature) hide glue of the 1 – 1 mix, add 2 ½ tablespoons urea (or 1 ½ tablespoons salt) for each cup of dry glue.
add glue to cold water and stir. Allow to soak for 30 minutes minimum. Heat gently (double boiler or water jacket preferred) to 140o F, stirring occasionally.
For a basic unit, simply mix the glue in a glass pint jar and heat in a saucepan of hot water.
Lower gram strength glues generally are slightly denser and different production techniques will affect the density values so the above mixtures will vary slightly with the grade. However, variables of temperature and water loss during use of the glue probably will have a more significant impact on concentration ratios than dry glue density.