Intro: Switch-Adapt Toys: a Steam Train Toy Made Accessible!
Toy adaptation opens up new avenues and customized solutions to allow children with limited motor abilities or developmental disabilities to interact with toys independently. In many cases, the children who require the adapted toys are unable to interact with most toys currently on the market, because they aren't able to effectively push, slide, or press the manufacturer's operating buttons.
This instructable guides you through the process of adapting a Steam Train that blows bubbles, with lights and sounds and bump N' go action! That is a lot of sensory stimulation in one!
In this instance, we are adapting the toy by adding a mounted female mono jack into which the toy recipient can plug in the switch of their choice (whatever switch they are able to control and operate).
Step 1: Wire Preparation and Jack Soldering
There are two types of mono jacks you may choose to add.
In our images here, we are adding a mounted jack, which will be mounted on the toy itself.
See our instructable about Preparing a Mounted Mono Jack.
You may instead opt for a female mono jack with a lead cable (not shown).
See our instructable about Preparing a Mono Jack with a Lead Wire.
Step 2: Toy Assessment
CAREFULLY remove toy from packaging. Do not destroy the box or packaging because we'll return the toy to make it look like new after adaptation so the recipient can receive an equitably 'new toy'!
Assessment: look to see how the train is activated. This particular train has a single slide switch (on/off) at the bottom of the train chassis (in the rear) behind the battery compartment.
Single-switch operation makes toy adaptation easy, as it is clear how we can replicate the function exactly with an external switch. The question is whether we would easily be able to solder our jack in parallel with the switch. To answer this question, we must open up the toy.
WARNING: the bubble making operation of this toy is VERY SENSITIVE. When you separate the bottom chassis from the top, do so slowly and only separate up to 1.5 inches between them.
Step 3: Toy Disassembly
This toy is not so easy to take apart. There are 6 screws: 2 in the rear corners, 2 between the center/middle wheels, and 2 in front of the circulating drive wheels. The parts labeled "STRONG motivation" are held by screws that do not need to be removed.
Carefully separate the top and bottom parts. They are still connected with VERY FRAGILE tubings that circulate the bubble liquid. If you note that these are broken, please find a facilitator.
Locate the on/off switch terminals where two wires connect (in the image they were yellow and red).
Find the contacts where the wires (that lead to the motor circuit) are soldered to the switch. We want to solder the wired female jack to the same contacts. However, you'll note they are embedded quite deeply in the toy.
First, make sure you've identified the correct points: Use a test wire (any small wire) to touch the two ends of the wire to the two terminals embedded deeply, thereby imitating the function of the switch. If your toy has batteries in it, the toy should turn on. CHECK IN! WITH A FACILITATOR TO MAKE SURE THESE ARE THE RIGHT LOCATIONS.
Instead of soldering directly onto the terminals, we will create soldering points on the wires connected to the switch (the red and yellow). We do so by locating a point 2" away from the switch terminals, and removing 1/8" insulation (very delicately with a wire stripper or knife). See the image how a knife lightly scrapes the insulation away, rather than cutting. Now we pre-tin the soldering points (meaning, putting fresh solder on the exposed wire).
Please ask for help if you're not comfortable doing this. These are very thin wires and can break easily.
Step 4: Wire Soldering
There is one free end of the cable extending from the female jack. There are two free wires (leads) at this point. The two leads are interchangeable. We will solder each wire to a single soldering point you just created on the red and yellow wires (i.e., do not solder both free wires to the same soldering point).
Be sure to follow the safety instructions for soldering.
Insulate: use nonconductive tape to insulate your new solder points (use small pieces of tape and fold it over the solder joint).
Test: with a switch plugged into the female jack, test the function of the toy (if you have to reinsert the batteries, please do so). The toy should activate as intended. Make sure that the bottom chassis has its wheels in the air so that when the toy begins operation, the chassis doesn't roll away (breaking tubings and wires in the process).
If the toy does not operate, begin by checking that no wires had accidently disconnected during the adaptation.
Step 5: Plan the Wire Exit
We need a plan for where to mount the jack on the toy. Typically we choose an area of the toy that isn't crammed with switches and wires, otherwise you risk interference with the toy operation.
In the train, we will create a hole centered between the tail lights of the train.
Make a 1/4" hole centered between the rear light stickers on the top half of the chassis. We typically make this with a wire or a sharp Philips screwdriver. Do not try to drill into the toy. The plastic is brittle and will break.
The hole you make should be just big enough to push the head of the jack through it, no larger. You MUST start small, and incrementally enlarge the hole to make sure that it isn't too big.
Holding the jack from inside with your finger (again, make sure you're not pulling the top from the bottom chassis too much), place the washer and then the nut over the jack neck. Hand-tighten the nut, then using small pliers further tighten (about 1/4 turn).
Now test that the jack works as expected (by connecting a switch to it and pressing it). Again, keep the wheels off the table to avoid unintentional movement and separating the top from bottom chassis.
Step 6: Final Test Before Reassembly
Replace the top onto the bottom chassis, slowly make sure no wires or tubings are pinched (especially the white tubing).
It is important to check that there is no interference between wires, parts and anything that may have moved during your toy adaptation. BEFORE you replace the screws, re-insert the batteries and test the function of your female jack, as well as the function of the toy (as it was before the adaptation).
Step 7: Toy Reassembly
If everything works as expected, screw the toy back together, and perform a final test. Please check out with a facilitator.
After testing, repackage the toy nicely, making it look as new as possible. If you wish, please fill out a greeting card for your toy recipient letting them know who you are and any holiday wishes.