Step 1
Rub a folded piece of sandpaper along the split to remove rough edges and form a smooth bonding surface. Use medium grit for very rough edges and fine grit to smooth.
Step 2
Spread a high-quality wood glue in the split, making sure to cover the crack thoroughly over its whole length.
Step 3
Place a bar clamp across the table. Use more than one clamp for a large split, making sure to space them so that there is even pressure distributed along the split. Put a folded dishtowel or another kind of padding between the end of the clamp and the table to prevent damage to the table.
Step 4
Tighten the clamp until the split is forced together. Start with the center clamp first if using more than one clamp.
Step 5
Wipe off any wood glue that oozes out of the crack with a damp cloth.
Step 6
Allow the glue to thoroughly dry, and then remove the clamps.
Step 7
Apply lemon oil over the repair if it is not really noticeable, or touch up the repair with stain, and varnish the entire table.