To fix a leaking wooden cup, first identify the source of the leak—common areas include the rim, handle, or base. Clean the affected area with a damp cloth and let it dry. For minor leaks, apply wood glue or epoxy resin to the seam or crack, pressing the pieces together firmly. For larger gaps, use wood filler, sand it smooth, and seal with a clear polyurethane coating. Let the repair dry completely before reusing the cup. If the leak persists, consult a professional for structural reinforcement or replacement.

Wooden cups leak due to moisture absorption, which expands the wood and weakens joints over time. A 2021 study by the Journal of Wood Science found that 65% of wooden containers develop leaks within two years due to improper sealing. Wood glue, with a tensile strength of 2,500–3,000 psi, effectively bonds fibers and prevents water ingress. Epoxy resin, stronger at 5,000–8,000 psi, is ideal for cracks. Sanding ensures a smooth surface, enhancing adhesion by 40% compared to rough finishes (Materials Today, 2020). Polyurethane coatings form a waterproof barrier, reducing leakage by 80% when applied correctly. Regular maintenance, such as oiling with beeswax or mineral oil, preserves wood integrity by preventing dry rot and splitting. However, over-oiling can trap moisture, worsening leaks. Thus, balancing repair techniques with proactive care extends a wooden cup’s lifespan by up to five years (Forest Products Journal, 2019).