Sheet steel

BikinGlynn

Member
I would also counsel against it - this steel plate hidden under a patio (covering an old shaft) conformed almost identically to your specs, and we really struggled to move it about and it was a major pain in the arse cutting it up. And yes, it was rusty, sharp and very nasty to handle. Surely this is what our world of plastic was implemented for? ;)

View attachment 18988
we handle 10mm plates for breakfast ;)
 
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