1. I put the painting in a plastic bag. For small paintings I use 2 gallon zip bag, for large I use giant bags I get at Home Depot. This is just a tall kitchen bag.
2. I cut 3/4" styrofoam sheeting from Home Depot or Lowes the same size as the painting. I cut side strips 3 1/2" wide (the width of the canvas plus the width of the styrofoam x3) .
3. I build the styrofoam 'box' around the painting putting 2 sheets of foam on the face of the painting
4.I put extra pieces of foam on the corners and center sides for extra protection. If I'm shipping a framed painting I put 2 full layers on the sides.
5.I get Four Part Mirror Boxes from a moving company like Allied Van Lines. I like these because the largest paintings I ship are 30 x 40 & 36 x 36. Because of the overlapping of the cardboard I have extra layers in the center of painting. Makes for a sturdy box.
6. I fold and tape the cardboard box around the styrofoam box
7. Done and ready to ship. I won't guarantee that your painting will be safe with this method but it's worked well for me. The cardboard boxes cost me about $8 and the styrofoam about $11 plus tape so the total cost is around $20.
