Well, I found some 1" OD, 0.049 walled 4130 tubing so I decided to use that instead of the conduit. Probably not the best material but since I build aircraft I have tons of it available up to 23 feet in length. I polished it up all bright and shinny and then got lazy and just accepted the sizes, 3 x 36" and 3 x 48".
I built the table today. Basically it’s the standard EAA workbench except instead of 24" x 96" it’s 48"x60". You can Google it or just as me if you can’t find it.