Isinglass properties:
Contrary to other animal glues which solidify when cooled, the right dilution isinglass remains liquid at room temperature, it is therefore not necessary to heat the supports before applying the glue.
Insoluble in organic solvents.
Isinglass, like all glues of animal origin, is not water resistant. The bonding therefore remains reversible and can be removed with hot water even after years. Glue residues can be easily removed with a damp cloth. This feature makes isinglass very useful in the restoration of delicate objects where sanding or the use of tools is to be avoided.
Preparing the isinglass:
Add cold water to the solid isinglass (usually 100 g of glue and 700-1000 ml of water) and leave to soak for about 24 hours. Then heat the mixture in a water bath, stirring occasionally with a wooden or glass rod. It is essential that the water is not heated too much, the ideal temperature is between 50 and 60° C. Absolutely avoid heating above 60° C or even boiling water, as the glue would lose its adhesive strength. After about 20-30 minutes the glue is completely dissolved and ready for use. It can be diluted with water to obtain the required consistency.