I worked for many years on brake presses. The biggest one I worked on was a 600ton Cincinatti, which could bent a 20 ft length of half inch steel plate 90 degrees. Boy, I miss those toys.
Some types of aluminium bend a sharp 90 degrees with no risk of breaking, some have to be heated to make even a radiused 90 degree bend.On that stuff even a slight scratch on the back side of it will cause a crack.
I build all my hatches by notching out the corners of a piece of 1/8th inch aluminium and after having slight kinks put in corner to corner for stiffness, I have the four sides bent up 90 degrees. This leaves one four 3 inch welds on the corners, to finish a fine aluminium hatch cover. As a former brake operator I know it's only about 20 minutes work, so it doesn't cost much to have a sheet metal shop do it.