Characteristics of natural glues

	Casein	Fish	Hide	Rice & wheat pastes
Applications	tropical woods; structural lamination, panel and flush door covering; may produce glue lines with a thick appearance.	light-duty, wood-to-wood bonding; natural nonwood materials (such as cloth, metal and bone) to wood.	good combination of versatility, compatibility and strength; edge- and face-gluing, assembling joints; veneering, repairing and bonding natural nonwood materials to wood. also used for sizing, a wood conditioner and a grain filler.	bonding porous, pliant materials (such as paper, cloth and leather) to wood; commercial formulas require no cooking and are easy to use.
Availability/ using	requires careful two-step mixing with water.	ready to use; can be coloured with dyes etc; refrigerate to extend shelf life.	granules -mix with water and heat to 140°F before use; ready-to-use liquid hide glues also available; add water if glue thickens; add urea or salt to retard gel rate; can be coloured with dyes etc.	mix with water and cook before use (if required); add preservative to prevent mould growth; can be coloured with dyes etc.
Typical working time #	15 to 45 minutes	15 to 30 minutes	1 to 10 minutes	15 to 20 minutes
Clamp time #	2 to 8 hours	2 to 4 hours	10 to 90 minutes	3 to 6 hours
Cured working properties	cures hard, sands readily, but dulls cutting tools rapidly; permanently stains the surface of high-tannin woods such as oak and mahogany.	cures hard; machines and sands well; compatible with stains and finishes; reversible with water.	Cures very hard; machines and sands well.	Cures soft and flexible; Easily cut with hand tools; compatible with stains and finishes; reversible with water.
Cured properties	excellent strength, rigidity and durability; highly creep resistant; some gap-filling ability.	good strength, rigidity and creep resistance; not as strong as hide glue.	excellent strength, rigidity and creep resistance; thick glue layers can be brittle.	not strong enough for most structural wood-to-wood bonding.
Long-term properties	high-grade formulas have good moisture and solvent resistance; low-grade formulas have lower moisture resistance; can be subject to bacterial and fungal attack unless preservative is added.	Excellent heat and solvent resistance; poor water resistance; glue layers desiccate with time and becomes brittle.	resistant to moderate heat and moisture levels, despite reversibility; good solvent resistance and shock resistance; glue layers desiccate with time and becomes brittle.	subject to bacterial and fungal attack unless preservative is added.

# depending on glue formula, moisture content of workpieces, working temperature, atmospheric humidity etc