Modern American flags are made of polyester and nylon rather than cotton like the old ones. This is good and all for the quality of the flag but once it must be retired the material choice can be dangerous. When burned, modern flags made of nylon or polyester release carbon monoxide and hydrogen cyanide, which are deadly to humans and also have a negative impact on the environment. That's why burying flags is the future towards helping save the Earth while still respecting the symbol of the country.
These cases are cut out on a laser engraver for precision and so they can be custom engraved. They are also meant to be buried with a sapling so a tree grows from the burial site, which is both for a good memorial spot and to help the environment.
Step 1: Dimension Your Case
The cases are made to hold a folded flag so you must fold the flag to dimension it. The steps for folding a flag are shown in the image above. Once you have the tightly folded flag, you will notice it is an isosceles triangle: meaning the two sides that make the 90* angle will be the same length. Grab a tape measure and write down the length of the shorter sides and the length of the long side, and after that record the thickness of the folded flag as well.
Step 2: Making the Top
Now you start making the pieces.
I used SolidWorks and started with the triangular piece that will be the top and bottom of the case.
For reference my measurements were 14x14x19.8 for the case shown, and the thickness of material I used was 0.192in
Start by drawing out a triangle in SolidWorks of the dimensions you recorded, then inscribe a triangle inside of it that is the thickness of your material away from each line(first picture).
From there now we fix the corners because the laser engraver cannot cut at the 45* angle that would be needed to make the triangle's corners fit together as they are now. From the endpoints of each line on the inner triangle draw a perpendicular line to the outside triangle(second picture). Then once you have all the corners with the 90* angles use the "Trim Entities" sketch tool and select "Trim to closest" and get rid of the corners, leaving only the 90* angles you drew(third picture). After that use the "Trim Entities" tool to delete the leftover lines of the inner triangle(Fourth picture).
Now we add in the slots for the box to fit together. The length into the triangle will be the thickness of the material you are using and I used 2in slots. For the short sides I used two equally spaced slots and the long side I used three(Fifth Picture).
Then extrude it the thickness of your material using the "Extruded Boss/Base" function in features.
Step 3: Making the Sides
We will start with the short side(remember the two shorter sides are the exact same length because the triangle is isosceles). Also the process is the same for the short sides and long side, I will just show for the short side(The short side is what is shown in pictures for the example).
Measure the length between the corners using smart dimension to find what will be the length of our side. Open a new part in SolidWorks and draw a rectangle that is as long as the dimension you just found and as wide as the thickness of the flag that you measured earlier(first picture). Now to add the outward facing slot that will fit in with the one on the top and bottom piece, it should be the exact same dimensions as the ones on the top and bottom just outward facing rather than inward(second picture). Then it is as simple as putting in centerlines and using the "Mirror Entities" tool to add the slot piece to the other sides of the short side(third picture). After that use the "Trim Entities" tool to get rid of the lines beneath the slots(fourth picture) and then extrude the piece to the thickness of your material like you did with the top piece.
Step 4: Fitting Everything Together
Once you have all the parts finished and extruded, open a new assembly in SolidWorks and input your five pieces. From there use mates to assemble it and make sure everything fits together well.
Step 5: Saving the Parts As DXF Files
Once all the parts are done you need to save them as a SolidWorks part and then as DXF files. The DXF file will save the 2D shape of the part and the exact dimensions. The pictures above show the process, make sure that you select the proper view for it to make the DXF file out of. To save the part as a DXF file you choose Save as and then click the drop down menu and hit DXF, that will bring up the menu as shown in the first picture.
Step 6: Cutting Out
I use CorelDRAW to connect to the laser engraver.
Open a new document and set your workspace to the dimensions of the engraver table, then input your DXF files and cut them out of your material.
The picture above is my top and bottom before I added an engraving, you can add any engraving you want using corel, but I wont cover that because there are infinite possibilities.
Step 7: You're Done!
Once the pieces are cut out you can leave them as is or paint/stain them, whatever! Test out the case by inserting your flag into it and watching it fit perfectly. I recommend using wood glue to glue the pieces together and after applying wood glue use a thin layer of hot glue to hold it together while the wood glue sets.
The first four pictures are of a case I made for Wigwam Creek Middle School for their flag to be retired.
I will throw in some prototype pictures of some that I did as well as a final one I did for myself to show off. Thank you for trying this out and helping with the environment. To make an even bigger impact plant a sapling with the case, that way the tree can be a memorial and it replaces the wood that was used in the making of the case.