Bring Old Toys Back to Life

On a recent visit to my local tip/dump, I came across an original 70’s walking robot. Anyone old enough (me damn it!), might remember owning one way back when. The robots were designed by Horikawa, a Japanese toy manufacturer specializing in toy robots. If you would like top see some of their designs - check out this website.

But I digress... My tip has a shop where you can buy most things for a couple bucks. I’ve brought many a weird and wonderful objects over the years; it’s a great place to find the unusual.

The Horikawa robot that I found was able to walk (like a drunken zombie) and also has a drum inside that spins. The drum has some images which when shown through the front lens kinda has a 3D effect.

Unfortunately, my robot was damaged beyond repair. The batteries looked they had never been changed and had decayed badly causing a lot of damage inside the battery compartment. The insides weren’t too bad but a few of the gears had missing teeth and it wasn’t worth repairing.

I could have just left him for dead and stuck him on a shelf but that's just cruel. Instead I decided to bring him back from to life. To do this I added a new motor and LED’s and fabricated a bracket to hold everything in place. I also added a sound recorder and now he can speak! Lastly, I removed all of the old electronics and came up with a way to re-attach his legs to him body. You can either just have the LED’s on or Motor and LED together. This way it can be used as a night light or just a cool talking piece.

So this ible' is how I found an old toy and brought him back to life. The chances are you probably don't have one of these Horikawa robots lying around. No matter, there are plenty of other, vintage toys out there waiting to be re-born. Just check out your local junk / thrift / tip / granny's closet and I'm sure you will find something that needs a little love.

Bits and Pieces

1. Vintage Robot. I'd suggest you look for a vintage Horikawa type which is what I used. You really want to find one that is no longer working and needs some love. Try eBay, or your local junk shop.

- One I used

2. Geared motor – eBay

3. 4 x AA Battery Holder – eBay

4. 4 X AA batteries

5. Small hose clamp

6. A bunch of wires

7. Sound recorder module – eBay

8. LED (Bike Light) – eBay

9. A piece of sheet steel (I just used some from an old washing machine)

Tools:

1. Drill

2. Hot glue

3. Pliers

4. Screwdrivers

5. Small files

6. Grinder

7. Vice

Steps:

1. Remove the batteries if it has any. As you can see from the images, the batteries had been leaking acid over a log period and had totally corroded the bottom battery terminals.

2. The robot I used was held together with 4 screws. Remove these and put somewhere safe. I had an issue with one of the screws as the battery acid had leaked into the screw cavity and had corroded it. I couldn’t remove it unfortunately so had to pry the plastic apart

3. Carefully remove the arms and head.

4. Take off the spinning drum by removing the pin holding it in place

5. Lastly, give everything a good soapy wash

Steps:

If you are lucky enough, the motor mechanism and bracket inside the robot will be ok to re-use. Unfortunately, mine was quite brittle and damaged. I took the decision to remove the section and fabricate my own bracket.

1. Drill out the hucks holding the motor mechanism in place. Carefully remove the motor mechanism from the body of the robot.

2. Make sure that you keep the motor and drum holder together. You will need to use this later as a template when fabricating the new bracket.

3. Next remove the legs from the motor mechanism by prying them off the metal rods that they are attached to. They should come off a bit of twisting.

Steps

1. Inside each leg there is a metal rod. You will need to trim this with some pliers.

2. Next add some hot glue to the rod and glue to the inside of the leg. This will keep the foot from moving. Make sure when gluing that the leg is straight. Do this for both of them

3. Next add some glue to inside of the bottom of the feet so they won’t be able to move.

4. Top attach the legs to the robots torso, you will have to make a couple of adjustments to the leg. There are probably better ways to do this but this is what I came up with. First remove any pieces of plastic with a file that’s getting in the way. I had to get rid of some on the leg in order for it to sit correctly.

5. Once you have the leg sitting how you want them too, Attach it with a self-tapping screw through the battery holder section.

6. Lastly, use a sh*& load of hot glue so there is no way the leg will come away.

Steps

You will need a flat piece of steel to make the bracket from. The piece I used was from a dryer and was L shaped. This just make my job a little easier as one side ws already formed.

1. First, grab the motor mechanism and place it against the steel. Measure where the drum holes will need to be and also how big the motor section is.

2. With a grinder, cut out the shape that you need. Keep on measuring until you have the bracket the size you need.

3. Next drill the holes for the drum axle. Don’t make these too big as you want the axle to have a snug fit.

4. Test and make sure everything fits

Steps:

1. First you need to add a small hose clamp to the geared motor. this is how you will will be able to attach to the fabricated bracket. I also added some tape to the motor so the clamp would grip well.

2. Next decide the best position for the motor on the clamp. the position will depend on where the wheel on the motor will touch the side of the drum. Oh and the wheel on the motor is just one of the wheels from the bottom of the robots feet.

3. Drill and cut the bracket so the motor fits into place and attach with the hose clamp.

4. Last, test and make sure that the drum is connecting with the wheel on the motor. Adjust where necessary.

Steps:

1. Next you need to fabricate an arm for the LED's. I used a small circuit that I pulled from a bike light. You could use any type of bike light or even just rig up a few LED's yourself.

2. I put the LED's to the back of the drum so they would have best effect. It took a while to decide where to position them in the drum and work out how big to make the arm. Just experiment until you have the LED's where you want them. The arm is held in place with the pin from the drum.

3. Attach the bracket to the robot with a couple of screws and test with the drum in place.

Steps:

1. Initially was was going to use a couple of 2 X AA battery terminals to power everything. They fitted perfectly into the back of the robot but It wasn't enough power to drive the LED's. I rummaged through my parts bins and found the below battery holders. One is a 3 X AAA flat battery holder and the other is a 3 X AAA round battery holder.

2. I had to extend the wires so I soldered on some longer lengths and added a couple pieces of heat shrink.

Steps:

1. One of the battery holders will be used for the motor, the other for the LED's. Choose one to use and solder one end to the lever switch terminal that came with the robot. Make sure you thread the wire through the back section of the robot so it is out of view.

2. Next Solder the other battery wire to one of the motor terminals. Add another to the other motor terminal and solder this to the other terminal on the lever switch.

3. Test with the drum in place and make sure the motor moves when the lever switch is activated.

Steps:

1. First you will need to add a momentary switch somewhere on the robot. This will be used to turn on the LED's. I used a momentary switch as that is what the circuit used.

2. Next, solder the battery wires to the terminals on the LED's.

3. Lastly, solder some wires to the momentary switch terminals and attach the ends to the switch solder points on the LED circuit board

4. Add some double sided tape to the back of the circuit board and stick this to the fabricated arm. You won't be able to put the arm in place yet as the drum won't go on to the bracket.

5. Test with the drum in place to make sure everything works.

This is an extra step that you can do if you feel like it. I figured might as well try to improve him a little.

Steps:

1. First you will need to decide where to put the tactile switches, mic etc. Even though it made things a little difficult when wiring, I decided to add them to the front of the robot. Drill out the holes needed for the 2 switches, LED and mic.

2. Next cut the wires about half way on each of the switches, mic etc. You could de-solder but I thought it would be easier just re-attaching with solder and heat shrink. Plus you can add some masking tape to each pair of wires on the circuit board and write what they are for.

3. Lastly, hot glue the parts into place on the robot

Now it’s time to re-attach the wires. I used some single copper wire for this as it is stiff and shouldn’t bend and get in the way of the spinning drum

Steps:

1. Solder some longer wires onto the switches, mic, LED and add some heat-shrink

2. Next do the same thing for the speaker. I had to drill a hole in the top of the battery compartment for the speaker wires to go through as well.

3. Now you want to solder the extended pieces of wire to the circuit board wires. Trim the wires so you still can open the front of the robot once soldered to the circuit board. You want to make sure that there isn’t much excess as it will just get in the way

4. Add heat-shrink to all solder joints.

5. Use some good double-sided tape and stick the circuit board to the back of the battery section.

6. Lastly, place the batteries into the battery section and close with the cover

Steps:

1. I decided to add the speaker to the bottom of the head. It fitted perfectly and gave his voice a nice, robot sound.

2. Attach the speaker with some hot glue.

3. Place the head into the head section on the body

4. Make sure that you have enough hot glue on all of the wires before you close the body

5. Place the arms in their sockets and close-up the robot. Finish by re-placing the screws into the body.

That’s it!

Even though some steps were a little fiddly and I had to really have a good think about how to re-mount the motor, overall I’m chuffed about how he came out. I’m going to give him to my nephew so he can use it as a night light. The main problem with old toys is the plastic can before brittle. Luckily I didn’t have any major breakages and he survived the re-build.

The great thing about old toys is there is usually plenty of room to add new electronics. I would of loved to have got his legs working but this required too much re-work and I decided to sacrifice his movement for ease of build.

You could easily add an Arduino inside of one with a motion sensor and a few other cool sensors and have his limbs move more.. There is no reason why you could put wheels with servos in his feet and have him actually moving again.