This is my first Instructable. I built this train for my son's Halloween costume/ride. He wore the Tiny Pteranodon costume from Dinosaur Train so I thought he obviously needed a train. Let me know what you think of my creation.

Step 1: Make the Base Frame

First step is to build a platform. I decided to go cheap for this project so I used 2x3 boards for the exterior frame and then pressboard for the flooring. The press board is standard attic floor boarding which was about $6.50 at home depot. I screwed them together drilling down through the pressboard into the 2x3 with sheet rock screws. Because I was trying to also keep complexity simple I did not cut down the press board which came in a 2' x 4' precut sheet. The 2x3 boards were cut 4' long on the sides and for the short sides it were 18" long. For some added strength because my kid was going to ride this I used my kreg tool and did some screws from the long side 2x4s to the short side 2x4s, ie 4 one for each corner.

Step 2: Add the Back Wheels

First you make a wheel barrow before you make a four wheeled cart. I purchased some simple and cheap lawn mower wheels for about $5 each. Taking some spare 2x4s laying around I cut them so that they would be long enough for clearance of the wheels from the base. Using my drill press I drilled a whole two inches from the bottom and in the center of the board, about two inches in. To attach the wheel I used two nuts and a bolt. Two nuts are needed so that over time they don't unscrew causing the wheel to fall off. To attach the legs to the frame I used deck screws I had lying around because they were more than long enough to make it through the 2x4 and embed into the 2x3. I used two on each leg for strength.

Step 3: Making a Cart That Can Turn

For the front I need a way to turn the cart. To do this I drilled a hole through the pressboard and the center of the front end 2x3. I then took another 2x3 which was 20 inches long, which will allow for a 2x4 leg to be attached at each end. In the middle of the 2x3 board on the wider side I drilled a whole. Using a nut, and washer from the top side of the cart through the hole, in between the base 2x3 and the 20 inch 2x4 put two washers which will allow easy pivoting. Then I have a washer and two nuts on the underside holding everything together. The 2x4 legs are about 2 inches shorter than the legs on the back since they don't need to be as long. The 2x4s like the back legs also have holes drilled in them for the wheels. On the ends of the 2x3 screw in the 2x4 using two deck screws and one kreg tool screw. Attach the wheels the same way as the rear wheels. In order to control the cart I screwed a sheet rock screw into each of the outside of the front legs. I tied a rope connecting the two screws for pulling and turning.

Step 4: Front of the Train

I purchased a thing plywood board 4'x2' and cut it in half. Then using a self made compass I found the center and drew out a circle which touched the edges. I then drew a small circle in the center the size of a flashlight, bought a cheap one at home depot for $6. On the side of the board i designated as the bottom i measured up 3 inches and drew a line across for a "base". Using a jig saw I cut out the final shape and center hole using a drill bit to create a starting point when needed. In order to mount the train front I first used a scrap 2x3 board and secured it using 3 deck screws from the bottom of the cart base. Then using two drywall screws i attached the front to the 2x3 board. I made sure that it gave adequate space to the front pivot point.

Step 5: Making the Engine

To start off I cut a 2x3 just under the height of the front of the engine and then using the kreg tool. To ensure i had a strong connection with the screws I added a cross bar on the under side. I then took cardboard and rolled it so that it had a curve. I screwed one end into the upright 2x3 board and then hot glued the other end to the front. I continued this until the entire curved area was covered. After that I cut a section off which covered the square edge on the bottom of both sides. I hot glued the squared cardboard pieces to the front and then to the base of the cart. In between of each of the sections of cardboard I hot glued the cardboard, leaving just a little bit of overlap so that the hot glue would not show.

This was a slow time consuming part to get it just right.

Step 6:

I had an old plywood board lying around so I cut it so that it was 2' wide and kept the length as it was which was at the time about eye height with my son. So that I could at a later date have access to the engine area I cut a hole and added a door which I got from an old cabinet that I had lying around. I then screwed the board upright and against the 2x3. In order to give it some extra strength and so it didnt' move i then added a 2x4 against its base on the platform and screwed that down. I used a 2x4 because I had some extra lying around and didn't want to deplete my 2x3s. After doing a few dry runs with my son on it I decided to cut a section out of the top above the engine so that he could more easily see forward. I then began to build the cabin starting with the two front 2x3s and used the kreg tool to secure it into the 2x4 at the base. With that I screwed the upright back of the engine to the upright 2x3s with sheet rock screws.

Step 7:

I added the back upright 2x3s (adding a little extra length to compensate for the front 2x3s sitting on a 2x4). I start out with a flat roof. I originally measured this to be my son's height, but realized after i screwed the top down that it was too short for the hat he was going to wear so i removed it and designed a curved top for the front and back. I added a cross beam on the sides at the natural height for my son so he could have something to hold on to. With that I took an extra piece of plywood i had and cut it in half. Using that I put it on the sides of the cabin. The sides didn't go up to the cross bar so to fill int he space i took cardboard and screwed it in to cover the rest of the empty space up to the cross bar. I planned on adding motorized wheels to the sides which I took form an old robot. I measured out the size and shape on the side plywood boards and using the jig saw cut their holes on both sides. Make sure to measure before oyu do this so they're in approximately the same space on both sides. You can see the motor unit in the side board.

Step 8: PAINTING!

I painted the train in stages, attempting to keep with the color scheme of the train in the kids show Dinosaur Train. To keep the paint from bleeding over I used painters tape.

Step 9: Final Touches

On the front I glued in a flashlight I bought at Home Depot. I had soldering wires in the back of it so that it could be control from an arduino device. I used an Arduino Uno with a motor shield with three arcade buttons which had LEDs in them for the electronics. The first button was white and when pushed it would turn on the flashlight bulb (LED). Next there were red and green buttons, the red stopped the motors from turning and the green would turn the wheels forward. I glued a big wheel which I cut from foam core board to look like train wheels and in the front the little wheels were made from cardboard (I ran out of foam core board of the correct size). The front wheels were mounted on 1" PVC pipe which then was glued to the frame. On the large wheel I cut a similar section of PVC pipe and added a small piece of foam core on one end (a stopper) and glued the other to the bit wheel. For the connecting beam/piston/rod between he two wheels I used pipe foam for the front and glued two thin down (about 1/8th an inch) I gave enough space so the PVC pipe on the big wheel could easily slide. On the end of the two dowels I connected them with a small piece of foam that was glued on.

My son kept getting on and off during trials so I took a piece of plywood and a set of hinges and made a door. We kept it closed (locked) with a hook and eye. Kept him in it while we trick-or-treated.

After this I did some marker work and called it done.

Step 10: Final Thoughts

This is my first Instructable so I am looking for any suggestions or comments. You can see a brief video of the wheels working at the following link. (Train video)