I’m a big fan of testing circuits on solderless breadboards for quick prototyping and practice. I go into great detail about how to set up and use a breadboard in Chapter 12 of Robot Building For Beginners. But, in this article, I simply want to show you the choices that are available.
When I think of a breadboard, I think of this:
3M solderless breadboard with three binding posts and 840 tie points.
These large boards include binding posts that can accept either banana jacks from power supplies or multimeters, or wires from batteries. The plastic breadboard is screwed onto the painted metal plate, which provides some electrical noise isolation.
There are many manufacturers of similar-looking breadboards, but 3M is my favorite because of the quality of the materials and construction. The disadvantage is that the 3M boards are the most expensive.
Extra column in the center
of 840 tie point breadboards.
There are many boards around this size with a slightly different hole count (number of tie points).
For example, it is common to run across 830 tie-point breadboards, as opposed to 840 tie points. Usually, the difference is that the 840 tie point boards have an extra column of 10 tie points in the very middle of the board. An extra ten tie points isn’t a significant benefit by itself, but this usually exists to electrically separate the left half of the board from the right half. You have the option of inserting four jumper wires (two on the top, two on the bottom) to connect the power distribution buses, if desired.
For most circuits, it doesn’t matter whether you choose an 830 or 840 tie point board. But you need to be aware of the differences if you’re trying to copy a layout from someone who uses a different board.
Many projects don’t need that much space, so another common size of solderless breadboards is around 400 tie-points. These lack metal plates and binding posts, but are much less expensive.
Solderless breadboard with 400 tie points and matching PCB.
Eddy Wright (wrighthobbies.net) sells a printed-circuit board (PB400) that exactly matches a 400 tie-point solderless breadboard. This is convenient for transferring a design directly, hole-for-hole, from the solderless to the soldered board. You can buy the matching pair for $7.
Eddy’s PCB also includes mounting holes in the corners and plated-through holes for all of the “sockets”. Unlike most perf-boards that only have copper on one side, the plated-through holes mean you can solder a wire or part to either side and there will be an electrical connection to that row or bus. You won’t use up holes soldering jumper wires simply to connect to the single side.
For even simpler circuits, you can step down to mini breadboards. These have 170 tie-points, but lack power distribution buses (the long continuous rows on the sides or the top and bottom). When a breadboard lacks buses, they are called terminal strips.
Color solderless breadboards (red, blue, black, and green) with 170 tie points.
SparkFun Electronics sells these in white (PRT-07916) as well as a variety of colors (PRT-08800 to PRT-08803). The colors may help you differentiate between projects if you have a lot of breadboards lying around. But, the miniature size, color, and double-sided adhesive tape on the back suggests these boards would be excellent for mounting in a project. You can imagine one of these atop your robot’s head for experimenting with different sensor layouts.
The smallest solderless breadboards I’ve found come from Electronix Express. With only sixteen tie points, five tie points, or two tie points, these clearly are designed to be added to a larger circuit or project.
Tiny breadboards (overhead view on the top of the photo, underneath view on the bottom of the photo).
Underneath, notice the metal strips each have a metal flange where either a wire can be attached or they can be soldered onto a PCB. Also, notice the middle breadboard has a hole that is appropriate for an LED or sensor.
These all came from Electronix Express:
Check this out -- the RSR brand has a family of see-through solderless breadboards:
Transparent solderless breadboard showing the metal strips for tie points underneath.
In person, if you look closely from above, you can see the metal strips inside of the breadboard. Theoretically, this helps students understand how the connections are made. In practice, the board is just translucent enough to make it difficult to see.
However, with a little bit of work, you can see the metal wipes inside of the tie-point socket grip a wire:
Close up of a jumper wire in a solderless breadboard socket.
The board I received came with white double-sided sticky tape already applied to the back. This partially defeats the purpose of having a clear board. I wish they had included the tape in the kit, but not applied it.
Razor blade attempting to remove double sided sticky tape.
To remove the tape, I tried using a razor blade with partial success. The blade would occasionally cut into the plastic and the work was very slow going.
Blow dryer and paint scraper removing double sided sticky tape.
I read online that a hair dryer and dull-edged blade was a more effective method of removing double-sided tape. The heat softens the tape to allow it to roll off in a large chunk. While this was much more efficient than the razor blade, and there was no damage to the board, it still took a lot of effort and adhesive residue remained.
I did not have any adhesive remover, such as Goo Gone, Goop-Off, or Oops! So, I tried the following:
The kerosene was the most effective, but now the board smells awful. There are four or five cracks that either existed all along, formed due to the force of cleaning, or formed due to chemical damage.
Seeing through a clear solderless breadboard.
Electronix Express has sizes of clear solderless breadboards from 830 tie-points (03WCB102, $4.75) up to 3,200 tie-points (03WCB108, $26.95). SparkFun Electronics has a similar 400 tie-point board (PRT-09567, $5.95).
On solderless boards with binding posts, I'll usually hook up the power supply to the binding posts via banana jacks. With smaller breadboards, I'll just use the wires from a battery pack.
The standard tips of most multimeter probes are too thick to fit into solderless breadboard sockets. Usually, I'll add an IC hook tip to the multimeter probe, and have the hook hold onto a jumper wire that connects to the desired socket. Every once in a while, there will be a minor disaster where the hooked end of the jumper wire will stray into a socket or make accidental contact with another exposed wire.
Pomona solderless breadboard adapter from banana plug.
Electronix Express sells adapters that directly connect a banana jack (from a power supply or multimeter) to a standard socket-compatible pin. There is a black adapter (074691-0) and a red adapter (074691-2). The middle portion of the adapter bends to avoid having the cable in your face and to prevent the weight from tipping the breadboard.
The advantage of using an adapter is that it makes for a shorter, cleaner connection that doesn’t leave any exposed surfaces that could lead to unintentional electrical connections. Whether that’s worth $8.50 is a question of personal taste and experience.