Back in 2013, I made another of these shelving units. Before that, I had made 2 more of them, for a total of 3.
I really like these units because they are relatively inexpensive to build, and are very sturdy.
Back in 2013, I just had finished a project at my Son's house, which was finishing his basement. We bought a sheet of 1/2" MDF to cover the pool table during construction. After construction was done, he had no use for the sheet. I decided to make another shelving unit and consume the sheet, versus throwing it away. For another $32, I bought (8) 1x4x8's to make the shelf. I already has (4) 2x4x8's in stock for the legs.
There are several alternatives to which process to use to cut the 3/8" by 1/2" deep grooves in the shelf sides...that hold the 1/2" thick MDF shelves. One can use a router table, but it will take several passes because you can only route about 1/4" deep max per pass.
Another option is to set up the table saw to remove the 3/8x1/2 rectangle on 2 pieces. This takes a lot of trial and error set-up on the table saw.
I chose to use the dado blade option. It takes trial and error to set up the table saw fence and blade height, but you can run all the boards through in just one pass.
A while back I bought 2 clamps from Rockler that allow you to clamp a scrap piece of wood to the fence. You sacrifice the scrap wood piece versus running the dado blades into the metal fence.
I used my Kreig fixture to pocket screw the shelves together..........
Finished shelf frames
Counter-sink Drilling on Shelf sides
If you are building this shelf unit, select your 2x4's so they are straight and not twisted. I chose to use up 4 boards in my inventory, and they were either twisted to start with, or twisted over time. I had to use some bar clamps to straighten them as I assembled the unit.
This is a relatively low cost and quick to make shelf unit. It is sturdy enough to support heavy tools.
On the last unit I built, my son had a 7/16" thick piece of MDF left-over from another project.
My Fairbury lumberyard only had 1/2" thick MDF in stock, so I got that. I adjusted my dado set to give 1/2 deep and 3/8" wide grooves to set the shelves on.
I forgot how much fun it is to get the very heavy 4x8 foot sheet of MDF and up on top of 2 sawhorses in my garage. It was also 16 degrees F in my garage, but my Sears Evolve circular saw worked just fine.
On the 6th shelf, I split the difference of 17-1/4" into halves, or 8-5/8" wide for 2 pieces to make that shelf. I added a 1x4" board down the middle of the bottom shelf.
These units are fun to build, except for getting the heavy sheet of MDF up on the sawhorses, to saw out the shelves. I will probably end up making some more of these........it seems like I am always running out of storage space !