- Lay out all 4 pieces together.
 - Take two pieces and push the corners together, making sure the sharp edge is on the back and follows round. If it's a rectangular stretcher frame you will need two differently sized pieces for this step.
 - Take the third piece and push this into the opposite corner, turning it round to make a U shape.
 - Take the last piece pushing into the last top corners, making a square shape.
 - Use a mallet to tighten up.
 - Watch our step by step YouTube Video below!
 
