One thing that can escape us is that portable bench tops are subjected to twisting forces. IMO the best way to deal with this is to use some sort of stressed skin construction with a grid like spacer between and solid material around the edge and where legs would be mounted.
Boyd has a great idea! Consider the construction of a hollow core door. It has 1/8” plywood on both sides and solid softwood inside around the edges. The inside is nothing but a honeycomb of cardboard. The structure is glued together and is strong, straight, and light.
Try using 1/4” exterior plywood on the top and bottom and double 2.5” strips of 3/4” plywood around the perimeter and double 1.5” strips of 3/4” plywood on the inside for a grid. You would want to place double 3/4” plywood for leg points inside where needed. Use pleanty of wood glue, such as
Elmer’s, and staple or nail the thing together. Paint this top and keep it stored out of the weather and it will outlast you.
The top of my loading bench is two pieces of 3/4 plywood glued and screwed together. Is like a slab of steel. I put angle owrn under several edges to mount vise and barrel vise, no flex , works great. Should work for a bench top also, but not light.Building a portable shooting bench.
Which is more stable/less flex
1) laminate 3/4" plywood to 1 1/2"
2) single 3/4" plywood with two
3/4" sq alum tube stringers lengthwise.
The al would cut weight, but would it be as
stable ?
Thank you gentlemen.
I have limited time to get this up and running,
so while i like some of the ideas,
they will have to wait until next time.
I like the thin laminate core idea