Pots, kettles, brushes, everything that comes into contact with glue, should be regularly and rigidly inspected, and kept absolutely free from dust and dirt. This is extremely important.
USE COPPER AND BRASS OR ALUMINUM UTENSILS
An important aid to cleanliness is the use of copper, aluminum or brass for all parts of the apparatus with which glue comes into contact. Not only are copper, aluminum and brass the cheapest materials to use in the long run, due to their resisting acids in glue, water and steam which quickly corrode iron, but copper, aluminum and brass are practically self-cleaning.
Iron equipment is especially bad. It is most expensive in the end, for iron is quickly eaten away by acids in glue and water. Iron rusts, and the rust impairs the color and quality of the glue liquid. Do not use iron vessels under any conditions.
GUARD AGAINST EVAPORATION
A great deal of waste in the use of glue is due to evaporation. If glue is heated in open pots, evaporation is very great. Evaporation weakens glue; makes it too thick for use, and also makes it very uneven in quality. Glue should always be melted in a closed vessel.
DO NOT MELT TOO MUCH AT ONE TIME
As glue deteriorates quickly if allowed to stand, no more should be prepared than is needed for a single day’s work. It is even better to prepare it twice or oftener during the day.
If glue is dissolved at the proper temperature and kept at that same temperature after melting, no noticeable deterioration results during the course of the working day. But if allowed to stand over night its value decreases, and it should not be mixed with fresh glue, as it is not of the same consistency.
With practice and observation you can easily determine each day’s needs in advance and prepare each morning just the right amount.