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Adapt a Toy - Do it yourself 35 step by step Procedure - Instructions on how to solder and how to disassemble / reassemble  Jack Hammering Bob the Builder Toy   

Jackhammering bob the builder toy

 Toy adaptation for special needs handicapped children with disabilities.  Children who work with occupational therapists, and speech therapists need these switch activated toys.  If you need another toy adapted instead of this one, you can send it to me and I will adapt the toy and create a procedure like this one and put it on this web sight. EMAIL:  bdwhaley@scienceshareware.com

This is an approach that I took to make an adaptive toy out of Jack hammering Bob the Builder tm. It is now being used successfully at a local elementary school here is Olympia WA by special needs children.  This toy says 1 of 3 different phrases, then he starts running his jackhammer full tilt-  it vibrates and tickles when you touch it.  The vibration only lasts for 15 seconds.   

Note this approach to adapting Bob the Builder will NOT disable the existing button that is used to trigger it (this is a good thing so you can use it even when you don't have an adaptive switch handy).  This method of installing a jack will require you to install a small pair of wires from a PCB (Printed circuit board) to a 1/8" mono jack.  Take a look at the grey and red wire in this photo by clicking on this picture →  

This may take you two Bob the Builders before you get this right.  It is best to work about  1 hour  at a time.  This is because if you are impatient like me, you begin to get careless.  If you get careless you will mess up the toy.  Plan on it taking you 3 to 5 sessions to do this project.  PATIENCE and careful thinking is the most important part of this project!!!!

Materials needed:  Soldering iron, glue gun, scissors or wire cutters, sewing needle and strong thread,  an empty egg carton to organize all the screws in the order that you took them off, 1/4" drill bit, a drill, 1/8" mono jack (PN# 274-251 from Radio Shack), 8 inches of wire (size 26AWG  stranded, or size 28AWG stranded), wire strippers or strong finger nails,  a cheap $10 volt meter, a 1/8" drill bit, a small vice to hold your work while you are soldering it, safety glasses, a well ventilated area, small round file to size the hole for the jack if needs be.

Note: Do this project at your own risk, be careful and safe!  By using this procedure you agree to take full responsibility for toy damages or personal injuries. This is what can happen with a hot soldering iron.   Click on the soldering induced blister image below to see large version of the blister on the finger.

 finger blister from soldering iron safety

Below are step by step instructions for adapting the toy Bob the Builder with a 1/8th inch female jack from radio shack.    You can click on each picture to see a large view of that picture. 

First it is necessary to remove the batteries from Bob the Builder's back.  Don't worry, he won't mind.

Remove the screw from his battery area.  This screw is under the batteries, so you have to take out the batteries to see it and unscrew it.  Using a screw driver to disassemble toy battery pack

Cut the the thread that hold's Bob the Builder's hands to the handle of the jackhammer  procedure for adaptive toy - dissassembly

BE VERY GENTLE in pulling Bob the Builder's jackhammer out his abdomen.  Remove it JUST enough to unscrew the 3 screws on the back side of his jackhammer. (see photo of the jackhammer to the right)bob the builder modification for special needs


Next you need to take the screw out of each handle of the jackhammer.  See picture for details.Adaptive toy bob the builder take out screws step

NOW FOR THE SCARY Part.  The Jackhammer is glued together.  It  has to be gently pried apart.  The prying DOES break 3 small plastic guide pins but this is OK because the screws are strong enough to where you don't really need the guide pins.  See photo   Just go around the Jackhammer with your screwdriver gently prying along the edge.  If you have a hair drier, you might want to use it to heat upt he the jackhammer first so it comes out easier.   DONT LET THE SCREW DRIVER SLIDE OFF AND POKE YOUR HAND!!!! IT HAPPENS!   


Next it is necessary to remove the grey rubber button from off of the circuit board located in the jackhammer  NOTE!!!  be VERY gentle with this button.  It will tear easily!  Which means you will not be able to operate the Bob the Builder with the button that exists in the toy anymore.            


Next obtain a 1/8" mono phone jack  (see photo)

Simply lay the jack into the spot shown in this picture to make sure that it fits ok.

Now take a mechanical pencil and make the lead stick out 1/2" so you can mark the hole in the center of the jack.  You can use a small nail also to do this.  This mark is very important because it is where you will drill a 1/4" hole.  So keep the mark in the very center of the hack hole.  If you are off to the side just a little bit the jack will not fit correctly in this small area.  

When I tried to fit the jack in, it did not work at first because the small ring that screws onto the jack did not lay flat because some plastic was in the way. So I used my soldering iron to melt away a little bit of the plastic- please look at the photo.  DO THIS VERY SLOWLY.  A little at a time.  This makes really yucky smoke.  Do not breath it in.  Use a fan on your work area to provide fresh air.  

Now try and mount the jack to make sure everything fits.   See photo Modify toy with switch jack for special needs kids

Now it's time to prepare the ends of two wires to solder to the jack.  First strip about 1/8" of housing from the wire using wire strippers or your finger nails.   Soldering Wires Tin First

Now it's time to prepare the jack for soldering.  It is very important to heat the jack up hot enough so the solder will stick to it successfully.  The only problem with this is that it will burn your hands if you try and hold it.  So you must use a small nail, or small screwdriver, or a male jack plug to hold it still when you are working on it.  See photo 

Now you are ready to solder the wires to the jack.  Secure the jack in a vice or have some one hold it for you while you hold the soldering iron with one hand and the wires with the others.  

Now cut your two wires at about 6 inches and tin the other ends just like the photo. 

Now obtain a 1/8" drill bit (see photo) 

Using the 1/8" bit drill a hole as shown in the picture.  That the hole is just to the side of the spot where the grey rubber button used to be.  

Solder one of the wires down on the spot shown in the photo. This is pretty easy because there is a nice big spot to solder down to!!   

Now comes the tricky part.  Soldering the other wire down on the PCB (printed circuit board).  You must prepare the area by scratching the green photo resist layer off the trace (see the photo) You can use a small piece of sandpaper or sharp object for this like a small screwdriver.  WARNING!!! DO NOT SCRAPE TOO MUCH , you will damage the copper trace that lies just under the green layer of film.  BE VERY PATIENT!!!!!! 

Now that you have prepared the spot to solder down the 2nd wire, you can get your other wire and solder it down.  BUT First, put the two wires  through the hole you drilled with the 1/8" drill bit.  Just like this photo.  NOTE!!! The spot where the grey wire in the picture is connected is VERY delicate!!  Do not pull on it. Be very patient and gentle!!!!!!  

Now put the rubber button back onto the circuit board. (See photo)

HOT GLUE GUN- It's time to secure the grey wire using a hot glue gun or epoxy.  See PHOTO

Next it's time to glue gun the spot where the wires come through the 1/8" hole.   NOTE:  Only put a little bit and flatten it out with a flat something - (like a flat screwdriver) because if you put too much, it will slide back into the spot where it came from.

Next you can put some hot glue on the jack to make sure the Bob the Builder's Jackhammer does not shake the wires loose after a couple years of heavy use.  This is your choice to do .  I'm just being cautious.

 Next it's time to test the electrical connections.  This is a sanity check to make sure everything is working as it should.  Put the batteries back int he back of Bob the Builder.  NOTE!!: At this point Bob the Builder is LIVE!! If you touch the jack with something that is metal, it might cause him to start jumpin around all over the place.  If this happens, just stay calm, and remove one of the batteries out of the back before some of your wires get ripped off of the PCB.  Turn on your volt meter to measure a DC voltage under 10Volts.  Measure the voltage at the terminals of the phono jack.  You should get between 4.0 and 5.0Volts.  See the picture:   If you short a screw driver across the two wires, it should wake up ol Bob the Builder - but pop out the battery as soon as it happens!

If you don't get the 4.4VDC rating, make sure your volt meter is working by measuring the voltage on each of your batteries.  Each on should be 1.5 volts or so.  Also, check the orientation of the batteries that you installed to make sure they are positioned correctly.   If you can't figure out what is wrong, send me an email with a picture of your wiring, and I will try and help you.  EMAIL

Now tighten the ring that holds the jack in Bob the Builder's jack hammer

 This is what it should look like at this point inside of Bob the Builder's jackhammer

Now it's time to re-install the PCB. There is one problem here.  Do you remember where you drilled the hole with the 1/8" drill bit?  Well if you put too much hot glue there, you will have a  tough time sliding the PCB back in.  So BEWARE!

OK, Now you are ready to put Bob the Builder's jackhammer back together.  Note: this is where you BETTER make sure it works first.  Push the button! 

Remember that 3 of the glued posts got broken when you pried this apart.  It's best to remove them if they are not going to slide nicely back into the respective holes.    MAKE SURE your red button is back in place.

Now put the screws back in and put new thread back into the handles to hold Bob the Builder's hands correctly.       

Put the batteries back in and plug in your switch and give him a whirl!!  Here are some typical switches.     Switches


EMAIL:  bdwhaley@scienceshareware.com



Bob the Builder is a trademark of  Playskool Toy  Corporation.