We like our cat, like obviously, way too much. His name is Captain (Captain Jack Harkness, you Whovians). Since Captain was a kitten we have wanted to build him a cat tower, but we just haven’t been inspired. (It's for him, but... it's for us too, ya know?) Do we want a regular carpeted cat tower? A Tardis cat tree? A Harry Potter cat castle? A hanging Death Star kitty lounge?! There are so many fandoms we love! But we needed something big for our big boy. Of course we had Star Wars on in the background when we realize the mission that needs to be accomplished: The Empire Strikes Cat. Our most favorite weapon of terror - however awkwardly shaped: The AT-AT, or the All Terrain – Armored Transport. Boy, were we inspired. For one, so many name options. ie. CAT-CAT. FAT-CAT… More importantly, there were straight legs for scratching posts, a big body for a secret sleeping cubby hole (cats love!), and fun opportunities for cat toys like mini Stormtroopers and a Snowspeeder wrapped around the legs. A couple hundred hours later, I present to you, the 1:21 scale CAT-CAT.
**Cat is not to scale
Materials and Supplies:
- 1 sheet - ½” Plywood
- 1 sheet – ¼” Surply (primered plywood)
- 1/2 sheet – ¾” Plywood
- 5 -- 2” x 4” x 8’
- 1 -- 2” x 6” x 6’
- 1 – 2” x 8” x 6’
- 2 -- Brass hinge
- 1 – 4” Semi-rigid dryer duct
- 1” Wood screws
- 2” Wood screws
- 3” Wood screws
- Wood putty
- 1” Brads
- ¾” Staples
- 1-1/8” Staples
- Wood glue
- Red taillight adhesive film
- Behr Premium Plus -Engagement White
- Black paint pen (would suggest grey if available)
- 1 yard -- grey fabric
- 1 yard -- batting
- 2 pages iron on fabric
- 1 package – adhesive backed Velcro
- Grey corded rope
- White paint/ fabric/ base cover
- Tack cloth
- Table saw
- Arm saw
- Circular saw
- Band saw/Scroll saw
- Jig saw
- Hole saw
- Brad gun/staple gun
- Air compressor
- Drill press
- Cordless/Corded screw gun
- Drill bits
- Belt sander
- Palm sander
- Putty knives
- Drywall square
- Chalk line
- Paint brushes
- Scratch awl
- Compass (circle drawing kind)
- Center punch
- Saw horses
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Step 1: Planning
The first obstacle for this All Terrain Walker to trample was how big we wanted to build it. We didn’t have the blueprint plans for any rebels to steal while making our CAT-CAT, so we needed several good reference pictures. After finding a bunch online we had to decide how big we wanted our CAT-CAT to be and how much fear we would strike in our enemies' hearts. We knew we wanted something around 3’ 6” tall and as proportional to a “real” AT-AT as possible. Using our reference picture we decided that every inch on the pictured AT-AT would be 7” in real life. For example, our reference roughly 4" long legs, so that means our legs were cut at 28” long. This turned out to be a surprisingly simple ratio, and we rarely deviated from it. This proportion also gave us just under our 3’ 6” height.
Since we wanted our CAT-CAT as realistic as possible, we knew we could not start at the bottom and build up. The way the hips articulate and attach, it would be easier to start with the mid body and build out from there. After the body, we made the head and then tackled the legs, being careful to keep all loose cables away so we wouldn’t trip the CAT-CAT up (until the last step, of course). We attached the legs to the body and base and then added the feet. From there we started detailing and overlaying the ankles and legs, moving up and armoring the body. Finally, we detailed the head with overlays. All of this was designed and custom fit on the fly; we tracked our measurements and angles at first but quickly realized the futility of our actions - there are so many parts, angles, and bevels, and wood is never perfect. So treat all our measurements (if given) with a grain of salt and consult your reference pictures often. That said, one of our most common angles used was 15 degrees. If you have an angled piece you need to cut, it is recommended you start at that 15 degree angle and add and subtract degrees from there. So without further ado, let’s do this!
Step 2: Main Body Chassis Frame
First, we cut out the floor of our CAT-CAT main body. Find a reference pic that shows a top-down view. When you look from this view, you’ll notice that the AT-AT tapers to the front and back. We cut out our floor in a rectangle first using the circular saw to make a rough cut ½” wider than the piece we needed. We then used the table saw to trim an ¼” off each side to get down to our final width. Last, we used an arm saw to cut the length we needed. (We used this same combination of circular saw, table saw, then arm saw for the majority of our cuts; it helped us get the straightest, most accurate cuts.) We then marked out our tapers. They were short enough to cut out on our arm saw. If your arm saw doesn’t have a deep reach, make the cut using a circular saw or lightsaber.
After the floor was cut we then built the frame for the hips and legs to attach. Using our reference we made this hip frame short enough to be hidden by the teardrop shaped hips, and proportionally wide - about 22-1/4” long by 5” wide. You won’t be able to see very much - if any - of it when all the CAT-CAT details are added.
On the top and bottom of the floor find and mark the center line of both the length and width. Use the reference points often to make sure you keep everything symmetrical. Next, we centered the hip frame on the body floor and drew lines to mark where it would go. Then, apply a thin line of wood glue to the top of the hip frame. Place your body floor on the hip frame and press down and wiggle into place. (Literally wiggle the piece as it helps activate/set up the wood glue.) After its centered and in the place you want it, use the staple gun and add a few staples to hold everything together. The staples act like a clamp and hold everything together while it dries. Fill in the staple divots with some wood putty because next we’ll start adding walls.
To make the center section walls we first cut out the plywood. Use your reference to find your height and width, and then rip a 1x2 and a 1x1 out of one 2x4. Remember 2x4’s are actually only 1-3/4” x 3-1/2” because the Rebel Scum at the big box stores like to lie to you! Frame out one side using the 1x2’s for the uprights (see pics for the orientation). This will be the wall opposite of the drawbridge door entrance. Before you frame the door side, make sure you measure, mark and cut your door out. We used a combination of an arm saw and scroll saw to remove the door. We eventually used that same cutout as the door later, so don't throw it away. Attach what’s left of your door panel to the frame. Use a slightly wider board on the top to form a lip the door can close against when in its upright and locked position. Now attach your two walls to the floor. They need to go in the center section, right where all the tapers begin. Glue and staple the frames in, again using pressure and a wiggle to set the glue up. We used two staples in these pieces. If you hang the floor over the edge of your work table you can staple without having to flip it all over.
Are you feeling confident? Feeling like this is going well? Good, because now here’s where the fun begins. The face and butt sections of the body not only taper down from the top and the sides, they also taper in less than a 90 degree angle. We played around with this a bit, and using 15 degree angle cuts and angles close to that, we were able to make walls and frames like the center section. Cut your plywood for the walls, and add in the angled frames to make it all as flush as you can. This is not for the faint of heart. We guessed, cut, and re-cut, taking just slivers of angles off until we were happy with how all the angles worked. For the front and back walls we intentionally inset them. We did this for two reasons: one it looks look that in “real life”, and two we didn't have to cut more angles to make everything flush. We also added a 2x4 behind the front wall where the neck will connect. Make sure you pre-drill and countersink two holes for the neck to attach to, as you might not be able to get a drill into the body later.
Don’t worry if you’re not quite flush around the edges; that’s what the wood putty is for. Also, make sure you’re gluing everything before you staple it together for the most secure hold. After we were done with the walls we noticed we didn’t quite have the center section as raised as it was supposed to be. This was easily remedied by adding a 1x1 frame and then adding the roof. The "shoulder" and butt sections' roofs were glued and stapled to the wall frames after the edges were angled to match the wall angles.
Step 3: Head Frame
For the head frame, we followed mostly the same process as we did on the body. Cut out the floor first, then cut and frame the side walls. Your angles don't have to be perfect on this one, as neither General Veers nor your cat will be able to crawl in this part to judge your shoddy craftsmanship. We again added a 2x4 for the neck support and glued and screwed the head permanently to the neck. We did not attach the roof of the head permanently - and instead countersunk two 1” wood screws into the frame - so we could eventually install red LEDs to light up the viewport! Lastly, we took the bottom of the head to the belt sander to notch out where the heavy laser cannons would go.
Step 4: Legs and Hips Frame
The legs for this had the potential to get really complicated. While we wanted the CAT-CAT posed mid step as if to crush some rebel scum, we decided our cat's safety was more important and that all legs should be on the ground. We found a reference that had all straight legs and thought this would be the easiest and most structural configuration.
Cut four 2x4’s 29” long. Then find a point centered and 14” down from one end that we will call the top. Use the scratch awl to make small hole. Put your compass in the hole and extend the pencil end to the edge of the 2x4. Then use this radius to draw out a circle. Keep this radius and mark it out on a scrap board or piece of paper as we use this radius for other details. Use that same radius to draw out a circle as close as possible to the top of the leg. You’ve just marked the hip joint and the knee joint for one leg. After marking the knees on all, take the legs to the scroll saw and cut out notches to give the illusion of articulating knees.
Next we get to make the hips. These are the teardrop shaped pieces that help the body stay level as the CAT-CAT marches forward to battle. For these we used the same radius we used for the knees on one side, and the other side was a small, metal coffee can. Use your reference and find out how big you want your hips and you can use the compass to draw the other circle. Then connect the lines so you have a teardrop shape. The small radius will eventually mount to the body, while the large radius will mount to the legs.
So let’s do just that. First mount the hips to the legs. We countersunk and pre-drilled a 2” wood screw. DON’T glue this one in yet. We will glue after we level the body. Next, countersink and pre-drill the hole to attach the hips to the frame. Now were getting somewhere! (Get it? Because the legs are attached? No, okay.) Next we need to position the legs and prep them to level the body.
First let’s cut out our base/pedestal. We originally wanted a 29” x 48” pedestal so the whole CAT-CAT had base under it, however, it was too big and we later cut it down to what you see in the final pics. We liked the organic shape better anyway.
After you cut the base, place the CAT-CAT on top of it. Position the legs in the stance you want, and raise and lower the hips to level it out. Make sure you level in both the length and width dimensions. Then mark the orientation where the legs meet the hip joints; you will use this line later. Use a 1x1 (or ruler) to mark a straight line at the bottom of the legs. Remove the legs one at a time and cut to make them mount flush and level. Then, glue and screw the hips and legs together using the marked line from earlier and attach to the body. Next, position your CAT-CAT on your base and glue and screw it in with the 3” screws. It helps to mark the area from the bottom and top again, so you know where to position your screws.
Now the structural work is over! Give your CAT-CAT a push; I bet a rebel snowspeeder couldn't knock it over! Seriously though, test out your CAT-CAT. Is it strong enough to support your cat? Even though Captain is more like Jabba the Hutt, the CAT-CAT was more than strong and stable.
Step 5: Feet
Nothing is more iconic than that first encounter with the Imperial Walker. You can hear the clang and thunder as it walks. A Rebel pulls out his macrobinoculars and sees the AT-AT's giant foot. The camera slowly pans up and the hearts' of the traitorous rebels sink down below their boots. We want to inspire that same amount of dread with all the details we put into our CAT-CAT. The details you add from here on out really help bring your CAT-CAT to life, and the results are definitely worth the effort.
We started with the pads of the feet. First we ripped a section of 2x6 and 2x8 in half. Then, we placed the two halves together and measured out the radius of the bottom pad on the 2x8 using our reference picture. Cut out your four circles on the band saw, arm saw, or scroll saw. After cutting, use a belt sander or hand sander to smooth the edges as close to a perfect circle as possible. Do the same with the 2x6 and a smaller circle to give the foot the two-stack shape it has. Next, center the larger radius circles on the joint where the legs connect to the base. Mark and cut out notches with a jig saw or other saw so the foot fully surrounds the leg. Use a similar process on the smaller radius, making sure you center the small circle on the larger one. This is not how the Imperial Walker's foot connects to the leg, but we were willing to sacrifice looks for practicality and stability of the CAT-CAT. After everything is cut, secure the bottom circle with glue and screws, and the top with four brads or staples. Make sure you don't drive brads or staples into your screws.
Next, we added the toes. For this we cut a piece of scrap wood on the table saw in such a way as to reduce the amount of end grain in the diagonal side. The longer the grain on the diagonal, the less likely your toes will break in the long run. We only glued the toes down.
After the toes were glued on, we moved up to the ankles rockers. These have the same radius as the larger foot pad, but they extend straight down after a semi circle is complete. We cut our pieces out of 2x4's and made them longer than needed. Then we found a scrap 1x1 to use as a reference and held the rockers up to the leg and marked the angle. After cutting and fitting all 8 rockers, we countersunk a small hole and attached a small plug to look like a giant swivel pin. Little details like this make everything pop in the end.
Step 6: Butt
We built out the bottom of the rear using 2x4's by marking, cutting, and sanding them as close as possible to each other. The shape is a semi circle that continues up straight on both sides. The radius is the width of the hip support frame. From there we built up the triangle piece and added two pieces of overlay. The vents were made on the table saw by cutting out the vent rectangle, lowering the blade on the saw to 1/4-1/3 the thickness of the vent, aligning the fence, and making your first cut. Move the fence over a blade's width. Repeat until your vent is complete. Don't be like Darth Vader; use a push block to insure you complete this project with all your body parts. Finally add an armor overlay piece to the top, and the Butt is complete!
Step 7: Overlay Armor Details
No CAT-CAT is complete with out its armor! Otherwise it would be called a CAT-CT which sounds like a medical test and no fun.
From here on out, the order of operations isn't set in stone. We decorated the places as we liked, but we felt the armor overlay should be one of the first things. The cool thing is you can get as layered as you want. We really felt like the layers added a whole new dimension to the project and the more we added the more our CAT-CAT took shape. I wont go into details on every bit of armor overlay as the process is almost identical with every piece. First measure and cut the armor piece you want out of the surply (primered 1/4" plywood) . Next, sand down the edges to provide a clean edge. Then glue onto the CAT-CAT, with the primer side out. For small pieces you're done. For larger pieces consider using a brad or staple. Just be aware of what you're stapling into. Don't staple into straight plywood unless you have very small staples. Long staples and brads can leave sharp points inside the body, and I can guarantee your cat will not like that. So when you're done, ensure no Rogue Ones made it through to pester your Imperial Feline.
You can really go all out on this step and I wholeheartedly suggest you do. After you've put up your armor, add wood putty until the CAT-CAT is seamless. After the wood putty dries you may need to sand and add more. If so, wait until it is dry and sand everything flush.
Step 8: Door Platform
The belly of the CAT-CAT is going to be as cozy as the innards of a Tauntaun for Captain, but he has to be able to jump inside! If there wasn't a platform for him outside the doorway, he would have issues jumping straight into the hole. Using the earlier cutout as the platform/door, we screwed the door onto a short 2x4 that is wedged in between the hip joints. Hinges were added so the door does have the capability to open and close (we would just need to remove the 2x4). We will eventually put in cabinet magnets to hold the door shut when necessary, but for now we have done without. After hanging the door, we installed a detailed side piece that acts as a belly plate. On the door side, the belly plate is gapped, leaving room for the 2x4 brace, but is whole on the other side of the CAT-CAT.
Step 9: Base
As I mentioned earlier, to make sure the CAT-CAT was stable, we were initially going to leave the base the large rectangle. However, after realizing this thing could take a tow line from a Snowspeeder and not tip over, we decided to cut it down to a more natural "snowy" curve. To get smooth curves, I took a machine belt and laid it around the feet in a fluid pattern, marking with pencil. I then traced over my lines with a sharpie, cut with the jigsaw, and cleaned up with a hand sander. The base ended up being 36" long and 26" at its widest.
Step 10: Paint
Did you add all the details you wanted with wood? You could seriously add and add and add details with the AT-AT. For the sake of the finishing this during the pet contest, we had to move on. First is the final putty. During this whole process we have been filling in gaps with wood putty and sanding it down, but this was our final chance to fix any oopsies, fill in holes, or make sure the armor was connected and smoothed accurately. ie. Some crevices are filled but others are left to look like armor overlay.
Sand the CAT-CAT down one final time; we finished with an 80 grit sandpaper. We used the air compressor to blow off the dust and get in tight corners and then wiped down the CAT-CAT with tack cloth.
Now it’s time for painting, and let me warn you, you have about 7 hours ahead of you. As you might be able to tell, we painted the CAT-CAT in our living room. This is for three reasons: Missouri gets way too muggy and hot, and we didn’t want the paint to dry funny. We personally wanted to be comfortable while painting – out of the heat and to be able to listen to TV. And sometimes you have to paint on your back, which we didn’t want to paint for hours on the shop floor. Just make sure you lay a lot of cardboard and newspaper on the floor to keep it clean. Start by painting the under belly of the cat tower; this way, you can work from the inside to the outside and don’t have to stick your hands in the drying paint. I used the 1” brush for most of the CAT-CAT, the 3” brush for the top and side panels, and the teeny brush for the small details (especially around the butt area). The first coat took about 4.5-5 hours. I would say, “make sure you let your paint dry before you start your second coat.” But unless you’re a Jedi speed painter, you’ll probably be fine.
The last thing you will want to paint is the base. Because the AT-AT is featured in the snowy Battle of Hoth, we wanted a white pedestal. In the future we will likely cover with white felt, but for now we just used extra white paint we had in the house.
Step 11: Detailing Work
After being painted, the CAT-CAT details just pop! But we wanted more dimension. We considered using a Dremel to inlay the doors and panels, but we didn’t want the tool to slip on the uneven wood grain and create an unfixable groove. Therefore, we used a black (we wished we had a dark gray) paint pen to add the details that we wouldn’t be able to with wood. First, we started with the big side panels and taped up an AT-AT picture where we could easily access it. We then measured out the long lines, exhausts, escape hatches, and doors and figured out their distance from each other using the 1:7 scale. The lines were drawn in pencil as there is a lot of erasing in the beginning! Then you will use your paint marker to cover the pencil lines. Test out the paint marker and ruler on a practice piece first because the paint can sometimes run under the ruler (or tape line)! We had to use a ruler with a cork strip underneath to lift the ruler off the wood, that way the paint line was straight and didn’t bleed underneath. In this step, you can add as little or as much detail as you’d like. And yes, we watched Star Wars in the background for mental inspiration. If you need help on your detailing, I'm sure your cat will sit there in the way and watch you work.
At this time you can also add the red adhesive to the "eye" section and add the silver duct before screwing the head on. The red film is super easy to apply; just measure your eye space, leaving 1/4" or so around the edges (framing the red), and cut with scissors. Peel off the adhesive and press in place. For the silver duct, we measured the neck distance and cut the duct with a metal-cutting Dremel wheel. Use eye protection, as shards will fly, and make sure to fold the sharp edges in after you're done cutting.
Step 12: Decorate
Now we need to decorate and actually make the CAT-CAT for the cat!…otherwise it’s just a coffee table with delusions of grandeur. First, we wanted to add a padded bed. If you have a cat, you realize how finicky they are with where they sleep. Honestly, ours would rather sleep in a cardboard box than a fluffy bed, so the pads didn’t need to be thick. The top pad is easy; take the rectangle measurements (mine were 9.5” x 12.5”), add a half inch on both sides, and cut out two gray fabrics and one batting. Stack the layers - gray, gray, batting- and sew all the way around the rectangle, leaving a 3” hole. Clip the corners and turn inside out. Lastly, stitch with an 1/8” top stitch.
The inner pad is more complicated. I recommend taking measurements and creating a "T" pattern out of paper. Test the paper template before you cut and sew the pad, and follow the steps above to complete. You can use adhesive hook and latch strips (Velcro) to attach the pads to the CAT-CAT.
The Stormtroopers and Snowspeeder toys are created using iron-on paper. I printed out the desired pictures and then ironed them onto white fabric. I then cut out the Stormtroopers and snowspeeder, leaving a ¼” gap, laid them onto their reversed sides, and zig zag stitched around the piece, leaving a gap for stuffing. I stuffed with poly-fil and then finished sewing the raw edges. To attach the stormtroopers on the inside of the body, I hot glued on cord and hung them from the ceiling. For the snowspeeder, I wanted it to look like it was wrapping tow cable around the ankles trying to take down the CAT-CAT, like Wedge Antilles did in the Battle of Hoth. To achieve this look I hot glued cord to the rear of the speeder and wrapped it from the back right foot around the front, and hand sewed on thread which attached to the door base.
Lastly, to give our cat something to scratch on, we wrapped gray cord around the legs and secured with hot glue. We couldn't even finish attaching the cording before he attacked!
Step 13: "The Shield Will Be Down in Moments, You May Start Your Landing"
After everything is attached and dried, its time to present this weapon of terror to your cat. I'm sure they'll appreciate the hours you labored over the construction; it's got to be better than a cardboard box, right?! Captain had no reservations about jumping onto, climbing in, and generally exploring his new CAT-CAT. He LOVES his new toy and has rarely left it since he got it.
Also, please enjoy this behind-the-scenes kitty photoshoot. What a model.
We hope you like this project as much as we did and "do what must be done"!
Grand Prize in the