Cutting edges? Dimensions? Wood type?
Detailed plans here:
My husband used treated pine for our foot bridge and it depends on what your spanning as to the size. Ours was over a stream in the back yard and was at least 12' long (not sure as it was 40 some years ago. He had a stringer across the bottom span with uprights for the hand rails and the height was quite high as the spring ran high every spring. So I would thing it depends on what you are using it for. I would use treated lumber though.
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Yes, treated lumber.
All your fasteners and hardware will need to be compatible with that lumber.
”cutting edges?”, what do you mean? How to round the handrail in the picture: a belt sander and jig sawing the rough shape.
Here a detailed plans http://shoppingmatchmaker.com/freebridgeplans.htm
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