I have seen several Monster-In-A-Box videos on YouTube over the past few years and been intrigued by them. I haven't seen very many detailed instructions on how to put one together though. I wanted to build my first Halloween prop this year and I chose the box because I thought I could get a nice startle out of people with it and because I have little boys and I didn't want anything too gory around the house. I wanted the entire box to "jump" off of the ground, I wanted the top to bang up and down, I wanted it to snort fog and I wanted all of the movements and snorting fog to be coordinated with sound. This is what I built. This is not an original idea. It's just my take on this interesting Halloween prop.
I've separated this instructable into 2 parts. Part 1, The box and Part 2, The Guts. The build of this box can stand alone and be used for any number of projects requiring a sturdy wooden box if you don't cut the window and jail bar area out. See my other instructable "Monster-In-A-Box (Part 2, The Guts) for the second part of this build.
Tools used: Tape measure, t-square, Miter Saw, finishing nailer, drill, drill bits, circular saw or jigsaw, reciprocating saw, pry bar, hammer, wood clamps, chemical respirator, goggles, gloves.
Supplies used: wood pallets or old fence panels, 1x2's, brads, sheet rock screws, wooden dowel, wood glue, silver paint, hinges.
Step 1: Use Wood Pallets to Make Your Box
I chose to use wood pallets for my project because I could get them for free and the old pallets gave the box a nice weathered appearance. You could also use old fence panels. Depending on the size of your box you will need 2 - 3 old pallets. I used 2 pallets and ran out of wood before completing the lid. If you don't want to tear up old pallets, you can always make a trip to the lumber yard and make yours from new lumber.
I used a reciprocating saw to cut the nails and remove the boards from the pallets. That worked great for the nails on the outside perimeter of the pallet but not so great for the nails running down the middle. For those I used a small crowbar and hammer. It was time consuming even with the sawzall. When I realized that 2 pallets would not be enough to complete the box, I chose not to tear down a 3rd pallet but found some old fence panels to use for the top. They worked just as well.
A word about pallets: Many pallets are treated with harsh chemicals to prevent invasive insect species from being shipped overseas. Also, pallets can be contaminated with any number of things during shipping. If you use pallets, look for clean pallets that pass the eyeball test. Also, there are other instructables that go into detail about what the stamp markings on pallets mean and what type of treated pallets are OK and not OK to use. Please educate yourself before using pallets. If you use any type of treated lumber for your project make sure you use a respirator while cutting the wood and it is recommended that you use gloves and goggles as well.
Step 2: Use 1x2's to Frame Your Box
I decided to make the box walls out of a picture frame setup. I wanted to create a frame for each side of my box to attach my cut pallet pieces. I purchased 8' sections of 1x2 inch cedar from Home Depot. The 1x2's and the plywood bottom were the only wood I purchased for this. The rest is recycled. The amount of wood needed depends on how large you make your box. I wanted my box to be big enough that you could believe there was a monster large enough inside to hurt you but not so big that it took up a lot of storage space while not in use.
The first thing I did was lay out my pallet pieces to determine how tall the sides would be. Since I planned to place the pallet boards horizontally on my frames this would help me determine the height of my box. I didn't want to have to rip any of the pallet boards lengthwise since I don't have a table saw. Laying 5 boards out side by side gave me a height of 17" at it's widest point and that size worked well within my box size requirements. I took this time to determine the other dimensions of the box. I opted to make the box 24" long by 18" wide. The sides would be 17" tall before adding bottom and top panels.
I cut 4 pieces of 1x2 to make a frame. The frames for the front and back were 24" long by 17" high and the frames for the sides were 16" long by 17" high. For the front and back frames I cut the horizontal pieces 21" and the vertical pieces 17". The horizontal pieces got cut at 21" because they will be inset inside of the vertical pieces. The vertical pieces are 1.5" in width and there are 2 of them, so you have to deduct 3" from the total length of the horizontal pieces. Thus 24" - 3" = 21". Sames goes for the sides. The horizontal pieces for the frames on the sides of the box will also be inset inside the vertical pieces therefore the horizontal pieces need to be cut to 13".
I used a clamp to hold the frame sides together and a finish nailer with 2" brads to fasten them together. I ended up adding sheet rock screws as well later because the brads did not hold up well under pressure of the pneumatics. The brad nailer is nice, however, for tacking everything in place quickly during the initial build. You can add screws after to add strength to the joints since the box will be hopping all over the place.
Step 3: Cut Your Pallet Planks to Length and Attach Them to the Frames
I cut the boards that I had removed from the pallets to length with a miter saw. I wore a respirator mask and safety goggles while cutting the pallet wood because it had been chemically treated. In my case, the front and rear walls of the box were to be 24" in length and the sides were to be 16" in length. I laid the pallet boards over the frame and lined up all sides making sure it was a nice fit. I then nailed them to the frame from the back side with a finish nailer. I repeated the process for all 4 box sides.
Because I wanted the front of the box to have small jail-like bars I cut one of the front boards and left an 8" opening in the middle of that section.
Step 4: Nail the Sides Together and Add a Bottom
I made sure the sides were level and square and nailed them together with the finishing nailer.
Once complete I moved on to adding the floor. Since I planned to mount a pneumatic piston in the floor of the box that would lift the box up and apply a lot of force on the bottom, I wanted the floor to be sturdy. I chose to use 1/2" plywood for the bottom of the box. I measured the outside dimensions of the box and cut the floor to size with a jigsaw. I fastened the floor to the box with the finishing nailer. Later I added wood screws to the joints and floor for added strength.
I made the box lid next. I used the same outside measurements of the box I previously measured for the box bottom and made another frame just like I did with the walls. I added wood to the frame just as before to complete the top.
Step 5: Installing Jail Bars
I wanted this prop to have 2 red glowing eyes looking out and I wanted it to snort smoke. I set out to make some type of barred window for this purpose. The best thing I could come up with was to make a window frame out of the 1x2, drill holes to insert the bars into it and create bars from a wooden dowel rod. I have seen other boxes with these type of bars on the front I just wasn't quite sure how they did it. I measured the opening I had created on the front of the box and cut a window frame using 45 degree angles to those dimensions. I measured and drilled holes in the top and bottom pieces of the window frame. I cut wood dowel pieces with the miter saw to fit into the opening.
I painted the dowel pieces gray. I used Rust-Oleum Hammered. It looked great. They really looked like real metal bars but in retrospect I don't think anyone will be able to see that level of detail. I think plain silver or gray paint will work just fine and probably be cheaper. To paint the bars I put a screw in one end and tied a string around it. I held the string while painting the dowels and then I hung them up to dry. Once dry, I removed the screws and placed the dowels into the frame with Elmer's wood glue and nailed the frame together. I then nailed the frame over the opening in the box.
Step 6: Hinges and Final Assembly
Once the bottom and 4 sides were complete I installed 2 hinges on the back wall of the box and attached them to the lid.
I also decided to fasten (2) 1x2's across the bottom. I did so for a couple of reasons. First it would allow me to mount the air cylinder in the floor the way I wanted to. I also thought I might get a better rocking action this way.
See my other instructional "Monster-In-A-Box Part 2, The Guts" for the remainder of this project. I will be finalizing the second one in the coming weeks. I separated it into 2 instructables because I felt some may want to build their box differently and also because this instructable can stand on it's own for how to a build a box out of pallets. Thanks for viewing.