Originally shared by Sam De La Haye
Some of my old basic designs I thought I might share, might give some ideas or laughs!!! 
They seem like reasonable designs. The biggest design flaws I see in most designs (commercial as well) are wimpy uprights for the gantry and just general poor use of materials that end up way too heavy on the moving parts.
@David_Kirtley I would agree on that! The amount of knowledge I’ve gained in building the wooden one alone has been invaluable. I guess in wood its easier to see where things start flexing, moving and doing everything you don’t want them to do!!
Good work! You shared this project?
@Sam_De_La_Haye You can build something rigid from just about anything. You just take advantage of it’s strengths. You add other materials to compensate for it’s weaknesses. Like combining concrete and steel. Concrete is fantastic in compression but is lousy in tension. Add some steel to take the tensional load. Now they are using materials that are much stronger in tension than steel.
@Marcelo thanks! It’s moving along pretty quick! Other than the support of my family its just me 
@David_Kirtley I was wondering about that, is there ever problems with the water coming out of the steel and rusting the concrete? Or is that not an issue
Usually, it rusts a bit but the cement keeps most of the oxygen away.