DIY Sandblast Cabintet

     A sandblaster can be a useful tool in many types of projects. It can be used to remove rust or paint from metal, or to create custom etchings on glass and other materials. A sandblasting cabinet is essentially a box that is used to contain and collect the blasting medium (which can be anything from fine sand to glass beads and even walnut shells). A cabinet is not essential to the sandblasting process, but it is very useful for reducing clean up and making it possible to reuse the blast medium.

     I use sandblasting mostly for etching glass and stainless steel, and my setup is very simple. It consists of a small air compressor and a simple, inexpensive kit to adapt the compressor for sand blasting. The kit is nothing more than a nozzle attachment with a trigger and a rubber hose used to siphon the medium (multipurpose sand that I sifted through a metal screen) from a bucket. That set up worked just fine for my needs, but I wanted a way to recycle the sand so I did not have to make so many trips to the hardware store to get more. Also, finding sand in my hair and pockets was getting a little annoying as well. I decided I wanted a cabinet to add to my setup, but I wanted to make it my self, partially to save money and partially to keep up the diy/make-shift theme I had going while also practicing my newly acquired welding skills.

In this instructable I will show you how I made my sandblast cabinet from conception/design to use of the final product.

These are the tools and materials that I used in making my cabinet. There are certainly better ways to do some of the things I have done (some of which I will mention along the way), but this is how I did it with the resources available to me.

Materials:
     - 4' x 4.5' sheet of 16 gauge steel (0.0598" thick)
     - 2' of 1/8" angle iron
     - 2 steel door hinges (plus fasteners)
     - handle (plus fasteners)

Tools:
     - MIG welder
     - Oxy acetylene torch
     - Circular saw
     - Press brake
     - Slip roll

Note: Some of the tools above are not pictures of the actual tools I used, but I tried to find pictures that look as close to the ones I used as possible (and sources are cited).

     Before anything can get made, it must get designed. I am lucky enough to have access to CAD software at my university, so I was able to model my design on campus using CATIA. Pencil and paper works just fine though, especially for a relatively simple design like this one.

    My original design had handles on the top to make it easier to carry, and doors on both sides. I made a full size cardboard mock up of this design to get a better feel of the size of the final cabinet and make sure the dimensions I used were reasonable. This turned out to be a good thing to do, because it made me realize that I probably did not need it to be as big as my original design, and allowed me to improve functional features such as the angle and size of the viewing window, as well as the distance between the glove holes.

     With this new information, I refined my design. In addition to the modifications mentioned above, I also decided that the extra door and the handles on top were not necessary.

     With the finalized design, it was time to start thinking about materials and manufacturing methods. I wanted to reduce the total amount of welding that I would have to do, so I decided to make it out of one large piece (plus the door piece) and make it so it can be folded into the box shape and then welded at the seams when necessary. I made a new model of the unfolded box to determine how much material I would need and what shape to cut out. I knew the folded edges would need to be bent using a press brake and that 16 gauge steel was about the thickest material that could be bend with the press brake that I would be using. I also checked the thickness of another sandblast cabinet to compare and it ended up being only a gauge or two thicker than 16 (which could have been due to the layers of paint on it) so I felt ok with making mine out of 16 gauge.

    
      I used the circular saw to cut out the shape of the main piece, the door, and two 2" x 20" strips to be made into the glove rings. The holes (for the gloves and the viewing window) were cut out using an oxy acetylene torch with a cutting attachment. Ideally I would have preferred to do all of this cutting with a waterjet or CNC plasma cutter, as either of these would have been much faster and given much cleaner and more accurate results.

     With all the shapes cut out I drilled the holes (using a drill press) for the fasteners that will hold on the hinges, the door handle and the viewing window.

     In order to turn the flat sheet of steel into a box shape, a bit of bending is necessary. In the image below, you can see the all the places that I folded the sheet (dotted lines). The tabs on the right were bent first, and are there to create some overlap to aid in welding later. All the folds were made on a press brake. Because of the box shape of the design, the last couple folds get tricky due to the rest of the box getting in the way of the press brake. However, with a bit of improvisation and persuasion (aka several clamps, a hammer and a sturdy table) I was able to finish the last fold.
     The glove rings were rolled into 6" diameter hoops with a manual slip roll (excess length was removed with a foot shear)

     All the welding that I did was using a portable MIG welder. My experience with welding is somewhat limited so, as I mentioned before, I tried to reduce the total amount of welding required for this project. The welding that I did do was to seal up the places where edges of the folded box came together. The tabs I created during the cutting and folding steps made this part much easier, as they made it possible to clamp the sides together and the extra overlap made the welding easier and the welds stronger. I welded on the inside and the outside of each edge.

     Next I had to weld the glove rings to the inside of the box, around the glove holes. To do this I tacked one end of the ring/hoop to the edge of the hole, and then worked my way around the hole, tacking the ring every two inches or so, and then finishing it off with a continuous bead all the way around.

     After the welding was done, it became clear to me that with the box missing the entire left side (for the door) it was pretty flimsy in that area and didnt have much to help it keep its shape. So, I cut a length of 1/8" angle iron and welded it to the bottom of that side. This fix ended up working quite well. Then, using a pneumatic grinder, I cleaned up all the welds on the outside to make it look good.

     With everything cut and welded all that's left is assembly. The hinges, handle and viewing window are all held in place with fasteners purchased at a hardware store. The gloves I have are sandblasting gloves purchased online, and they are attached to the glove rings with hose clamps tightened well to hold them on.

     To use it I put the cabinet on top of a table, place the sandblast gun inside (with the hose coming out of one corner), open the door, place the work piece inside, close the door, put my hands into the gloves and grab the gun and start spraying! When Im done I can sweep the sand off the table and back into the bucket (and I dont have to worry about it in my hair, clothes and shoes).

     The cabinet works well as-is, but there are a few additions/modifications that I have been planing on making. First, I have not added a latch to hold the door shut while in use. It works fine just placing a block next to the door to keep it shut, but a latch (and maybe a strip of rubber) would help provide a better seal and keep in even more sand. I would also like to add a stand or some legs for it to sit on (instead of a table) to make it easier to collect the sand after use. Also, as you can see in the last few images, I never got around to painting the thing, so its a bit rusty. I may some day clean it up, sand all the rust off (or maybe SANDBLAST it off!) and give it a few coats of pain to give it some protection.