Question

how thick would it be if you used 4 1x3’s

Answer 1

If you use four 1x3's, the thickness would depend on how you arrange them. If you place them side by side, the thickness would be 3 inches. However, if you stack them on top of each other, the thickness would be 4 times the actual thickness of one 1x3, which is typically around 0.75 inches. Therefore, the stacked thickness would be around 3 inches.