If you know what a traditional solderless breadboard is, then you know that it's a beautiful and useful thing.

As times have change however, the breadboard – as traditionally designed – has, in some circumstances, become less than ideal. Again, in some circumstances, it has even become impossible to use. As electrical devices have become wider and wider (an ESP 32 for instance - as pictured above) they have become less able to be fitted into the fixed width of the standard solderless breadboard.

One fix for that problem is simple: divide the breadboard down the middle of the long axis of the board allowing the now split sides to be spread apart as widely as needed to accommodate any electrical device desired – with plenty of breadboard pins exposed on either side of the device (see last picture above).

I looked around on the internet for a solderless breadboard of this type to buy but I could not find any. So I got a “provisional patent” (#62622147) on the design and thought I would produce them myself. Problem is, I dont really WANT to become the “saw-the-board-in-two” guy for the rest of (or even a portion of) my life. Even for money. So I am writing this “Instructable” about the entirely simple process of sawing a piece of plastic (ie the solderless breadboard) in to two pieces using a hacksaw – mainly just to introduce the idea of it all.

Of course you can think of plenty of ways to cut a piece of plastic in two.
I am going to describe a method that uses an hacksaw and a simple miter box type jig I made to cut a 400 hole solderless breadboard in two, length-wise. This jig allows for pretty consistent cuts and maybe is suitable for a maker-space or some place like that where a number of divided boards might be wanted. This method is inexpensive as it uses materials you probably already have on hand.

Materials for making the jig:

~2 foot long 2"x4" board
jig sides (2) ~3" long piece of 2x1/2 hardwood
drill
screws
Popsicle stick (or similar)
Elmer's glue (or other)
~2 large clamps (to hold entire jig still)
square

Material for cutting the breadboard:

1 smaller clamp (to hold breadboard still)
2" wide masking tape
hacksaw
sandpaper

Step 1: What Is Being Made and How Does It Work?

The whole jig is clamped twice (as in the first picture above) to a surface - my kitchen counter in the above pictures - to hold the jig still while the sawing is going on. The solderless breadboard is also clamped down (with the smaller clamp) to hold it still while it is sawed (it is only clamped on one side - this holds it still during sawing and lets the un-clamped side move freely once the breadboard is cut all the way through - so that you know it is cut completely through.

You may have noticed that in the pictures above (and subsequent) there is an extra cut in the two side boards that guide the sawblade when it is cutting the breadboard. That cut was a mistake on my part (I didnt make a straight enough cut) so please ignore it.

Step 2: Making the Sides and Popsicle Stick Stop

The idea here is to make a kind of miter box at one end of the 2x4 with which to easily and accurately saw the 400 hole solderless breadboard in to two pieces. At one end of the 2x4 board, screw the two pieces of hardwood to the sides so that they are directly opposite each other and so the top edges are a little higher than the breadboard when the breadboard is lying on top of the 2x4. The two side pieces should be more or less level along the top edge. Mark a line (with your square) on the top of BOTH side pieces of wood showing where you want to make a cut in those side pieces to hold the saw blade straight while cutting the breadboard down the middle. Make additional lines with your square going down the side pieces to mark the path you want to saw. With the hacksaw, CAREFULLY cut down through the side pieces until you are cutting into the wood of the 2x4. If you saw too quickly, you might make a bent cut ( like I did above - I had to do it over again...). Correct the direction of your cut as you go in order to make a nice straight cut. Place an uncut breadboard between the side pieces and line it up exactly with the two side cuts so that when the hacksaw is cutting using the two slots as guides, the saw will be cutting exactly down the middle of the breadboard. With the Popsicle stick, saw or break off the ends of the stick so that it is just long enough to span the space between the side pieces of wood (e.g. the approx width of the 2x4), apply some glue to one side of the Popsicle stick and place the stick up against the long edge of the breadboard while the breadboard is placed exactly right to allow the hacksaw to cut it exactly down the middle (lengthwise). Carefully clamp the Popsicle stick down to the 2x4 and leave it clamped until the glue dries (maybe over night?). This glued down Popsicle stick will act as a stop so that you can position a breadboard exactly in the correct position to be cut down the center.

Be aware that, probably, there will be some protrusions on one of the long sides of the breadboard. When I set up the position of the Popsicle stick to glue down, I use the side of the breadboard that does not have these protrusions (the smooth side). Which ever side you use, you will need to place all subsequent boards in the jig (up against the Popsicle stick) with that same side against the Popsicle stick or the subsequent cut you make will be slightly off-center.

Step 3: Tape and Place Board for Cutting

In order to keep plastic sawdust out of the breadboard's pin holes while sawing the board, a piece of 2" masking tape is pressed onto the front of the breadboard over these holes. With the smooth edge of the board pressed against the Popsicle stick stop, you wont need to be able to see where the centerline of the board is in order to cut the board in half - the stop was glued such that accurately aligning the board for cutting is automatic - press the smooth side of the board against the Popsicle stick, clamp it there and the board is automatically align to cut down the center. In fact, I usually turn the board over (again keeping the smooth edge against the Popsicle stick), clamp it and cut it from the bottom of the board. This makes it even less likely that plastic sawdust will get into the holes of the board.

Step 4: Finish Up

Unclamp the divided breadboard, sand the cut edges of the divided breadboard, knock any plastic sawdust off of and out of the board. It is now ready to hold a wider electronic device while still providing access to all of the breadboard's pin holes... yey! :)

Happy hacking!