Gauge of material
the gauge is the wall thickness of the Corten steel. I only use heavy 14 or 11 gauge Corten or weathering steel for all of the planters and raised planter beds I create. Other companies use thinner gauge material such as 16 or 18 gauge. Be aware of thin gauge material because it has a much greater chance of bowing or bending when filled with soil and plantings and rain water. Overall, the thinner gauge material is less structurally sound. My weathering steel planters use only 14 or 11 gauge material and have incredible structural strength.
Top and bottom bent lips
When Steel is bent it become much stronger. My planters have too and bottom lips that are bent on a powerful machine called a press brake. This brake bends the entire edge of the weathering steel at a precise location along its length creating an exponentially stronger piece of steel. Always make sure that your planters are fabricated with these bent top and bottom lips / edges or at least a bent bottom edge if you prefer a straight sided planter.
Welded Corten Planters
If you want your Corten planters fabricated and welded and delivered to you in their assembled state please ensure that they are built using strong, consistent, stitch welds along all of their joined edges. You do not need the entire edges of your Corten planters welded and in fact it is preferable to have strong stitch welds placed every few inches along the lengths of all joined sides. This ensures that your weathering steel planter will not warp or bend during the welding process. Welding adds such I tense heat to the metal that if you were to have continuous welds all along he joined edges there is a very good chance that it will cause the planter to warp and bend. You do t want this to happen. Stitch welds are incredibly strong and form a super tight joined edge so you won’t ever have to worry about any soil leaking out of your beautiful planter.