I'm coming down with a nasty summer cold, but it's not severe enough to keep me from working on this project...at least today. So I start out by test fitting the remaining shelves.
Everything went just fine, so I proceeded with the cutting and mounting of the horizontal supports. About an hour and a half later, the storage cabinet frame was complete.
As can be seen here, the storage cabinet is essentially eight open-back 36"W x 45"H x 18"D boxes. This affords the structure a fair amount of strength and sturdiness with a minimal amount of framing. With the shelves individually rated for up to 200 pounds load each, this structure could conceivably store nearly 2.5 tons of material.
That's a little bizarre to contemplate now that I think about it...
Not one to waste time or space, I quickly set to work loading up the shelves. This also served as a good test to make sure everything I wanted to store would fit properly. I'm happy to report that everything fit with much room to spare.
If I'm feeling well enough tomorrow, I'll start bolting on the ¼" paneling on the top and sides of the storage cabinet. Then I'll get down to the business of fashioning the front panels and doors.