Steel Display Case- 3'2" X 1'0" X 0'10"

How to build a steel framed display case with simple wooden shelves for display of books or trinkets

Create your cut list, using only 1" box steel.
4x 3’8”
2x 3’6”
14x 0’10”
8x 1’0”
I cut my 28 pieces using a cold-cut saw, but you can use any saw that is meant to cut steel.

Begin by welding the rectangular frames of the three ladder pieces together. These do not require a jig, but in order for the unit to not wobble or tilt, it is important that each piece be perfectly square. To accomplish this, I used three clamps that would hold two perpendicular pieces of steel together at a right angle- something like this:

Measure and mark where the steel should connect, and tighten the clamps so that the steel stays in place. If an edge of the steel is standing proud of the one next to it, loosen the clamp and re-set until they are all even. Before beginning to weld, measure the diagonals of the frame to ensure they are the same, to double check that the frame is square.

Begin welding (make sure you are wearing the proper safety equiptment, including gloves, a welding jacket, and a welding mask)- on each corner, put a small bead of weld on one corner of your first intersection of steel, then another kitty-corner from that weld on the same intersection. Do this on all four intersections before finishing the welds. If any of the steel has slipped out of place, or any corner proves not to be square, it will be much easier to correct it at this step if there isn’t a full weld yet, so re-measure, or pull out a t-square and double check before moving on. If all is square, go back and fill in your welds, aiming for 2-3 lines of connecting circles on each intersection. Each weld should look something like this:

The inside corners should all get fillet welds as well, which is a weld that connects sides that are in different planes. Repeat for all three frames.

Next, fill in the “rungs” of the ladders. For the left and right ladders with the feet, there will only be two 10” bars added in, while the center ladder will have four. The steel has most likely warped a bit at this point, so clamps will be needed to force the long sides of the frames apart. I used this kind of clamp, and reversed one side so that it could be set on the inside of the frame and push the edges apart:

My steel had warped enough that even with the clamps, most of the pieces would not fit. I used a grinder to slowly grind down one side of my steel rungs until they just barely fit, and slide them into place. Use the perpendicular clamps again to hold them in the correct position, and measure to make sure they are perfectly square. Tack one corner, then kitty-corner, and then tack the other side. Fill the welds and the fillet welds, and move on to the next rung. Repeat for all rungs of the three ladders.

Grind down all the welds at this point, before we move into connecting the three ladders. They should be perfectly flat. If grinding the welds reveal any holes, fill them back in and grind them down before moving on.

Place the left ladder piece on the table, and mark where the first 12” pieces will connect. The 12” pieces need to be at a right angle to the ladder in two different planes. Use a metal t-square and place it on the ladder so that it points up, and rest the 12” piece of steel against it. Put a small tack of weld on the opposite side of the steel where it connects to the ladder, while still holding it against the t-square. Now shift the t-square 90 degrees so it is sitting on the other edge of the ladder, and repeat the process on the other side of the 12” piece of steel. It should now be tacked in two places, and be square to both the x and y planes. Add two fillet welds, and repeat for the other 3 corners.

Next, place the center ladder on top of the four verticals you just welded on, and double check that the center ladder is right side up. Use the right angle clamps to hold the steel in place, and measure the diagonals to make sure they match. Add a tack on two sides of each intersection, re-measure, and fill in each weld.

For the next set of verticals, you can use the right angle clamps, which makes life much easier. Again, because of each vertical needing to be at a right angle to two different planes, you must put down one tack with the clamp in one direction, then move it 90 degrees before putting down your second tack, then fill in the welds. Repeat for the other three 12” pieces.

Repeat step 7 for the final ladder piece

Stand up your case on a perfectly flat surface and make sure it doesn’t wobble

Now to make it pretty- Grind down any and all welds using an angle grinder, so that every weld is perfectly flat. If any welds are too weak, or have holes in them, fill with a new weld, and then grind down again. Repeat until the entire structure is perfectly smooth.

Switch to a grinder with a polishing attachment, with a heavy grit, and go over every surface until it no longer has any paint, dents, or uneven surfaces.

Switch to a polishing attachment with a lighter grit, and go over each surface with small circular motions to create a subtle pattern, and a more even sheen.

Wipe down the surface, and take the unit to a well ventilated area, either outside, or to a fume hood. Use a transparent spray sealant that is meant for metal, and spray each surface. This will protect it from rusting in the future. I used a Rust-oleum glossy spray for metal surfaces.

Create a cut list for the shelves-

4 @ 14”x10”

1 @ 27”x10”

1 @27”x12”

Cut the shelves out of any wood that you want, I used plywood. Make sure the wood it not thicker than 1”. I also had to trim down all of the 10” pieces by about 3/8” to get them to fit in due to a bit of warping.

Add rubber stoppers to the feet, attach the shelves with double sided tape meant for wood or steel (I want to be able to remove the shelves when transporting, hence the lack of more permanent hardware), and treat the wooden shelves with a stain or paint as you see fit.