How to Glue Underneath a Crack in Plywood

Ensure solid underlayments by repairing any cracks in the plywood.

As a commonly used, economical alternative to natural wood, plywood's versatility is evidenced in its wide range of applications. Plywood is made from thin veneers of wood that are mechanically pressed and glued together. Although plies are strongly adhered, weather, use and accidents can cause outer layers to separate, bubble and crack. To repair a crack, the raised plies must be relaminated by hand to the good plies underneath.

Things You'll Need

• Utility knife
• Putty knife or chisel
• Wood epoxy syringe
• Toothpick or Popsicle stick
• Concrete block or books

Instructions

1. Push down on the bubble to assess how well the lifted plies will lay flat once glued. If the wood is slightly warped and will not lay flat, make a tactical slit in the middle of the bubble with a utility knife to relieve the bow.

2. Insert the blade of a putty knife or chisel under the raised plies on one side of the crack. Lift up slightly to keep the crack open.

3. Insert the tip of the wood epoxy syringe under the raised plies. Extrude a small dollop of epoxy. Try not to extrude too much glue or it will ooze out when the plies are pressed back down.

4. Lift the plies on the other side of the crack. Insert the syringe tip and extrude more epoxy.

5. Spread the epoxy under the plies, using a toothpick or a Popsicle stick.

6. Flatten and weight the plies down with a concrete block or several books, and let the epoxy cure.

References

• Woodworking: Easy (and Instant) Crack Repair