big rim

grabcad

step1: divide the total length of the object by two, then do the same with the objects width and height.step2: create two center lines, one vertical one horizontal by doing this you can create a line that can be used to mirror across and a line to use a an axis for rotationstep3: sketch quarter of the object using correct dimensions. step4: then once all dimensions are created you can use the construction line you created as the line to mirror, select everything sketched and click the construction line to mirror using the mirror entities tool.step5: once this is complete use the revolve boss/base tool and select your structure and click the construction line created earlier to use as an axis of rotation make sure the rotation is set to 360 degreesstep6: configure the weight of the object you created to 1060 alloy