If you use plastic construction grade pipe as they use for gas lines it will last a long time.I made a couple that I have been using for years.The only thing that took time was the laying out of the holes to be drilled.I cut the front on an angle and ground the bottom to make an edge that would penetrate the sand easy.What makes it nice is you just run the scoop over the detector head.No metal=less work.The hand scoop, just cut a slot the size of your hand and cement a piece 1/2" tubing for the handle on top.For the back end I cemented clear plexi-glass and drilled.Just don't space the holes too far apart.The sand will lay there. Good luck if you build one.They are easy to make.