Rake Rocks and a landscape rake

[DDT]

Keep in mind a HD wall pipe is stronger that soild shaft.
This comment was made with some expereance I have had. I have used soild shaft for pins and they bend easy. I use heavy wall pipe the same size and no more problems. I am guessing here. I think the shaft is mild steel the only thing I can get in my area and the pipe is stronger materail. But You learned me a bit. Interesting I would have never guessed. I never took any classes to cover that stuff. Just seat of my pants.

 

[keeney]

There can also be an effect where the material in the center of the solid shaft prevents the stress from distributing and tends to concentrate it more. The hollow form allows the walls to flex in an adidtional degree of freedom (buckling inwards), spreading the stress across a larger portion of material.

So its not correct to say that the hollow form is stronger for a given diameter, but in terms of strength-to-weight (or strenght-to-dollar) ratio, it is, and also in terms of forgiveness / brittleness, it is.

- Rick