micro:pegs

How do micro:pegs work?

About a centimetre of insulation is stripped from the end of the wire to be connected. The bare end of the wire is pushed down though the 4 mm terminal hole and folded back on itself. A micro:peg is then pushed into the hole to hold the wire firmly in place. 

Multi strand wire works best but for single strand wire, or when connecting unwired components, the groove in the micro:peg can be lined up with the wire to make space for it next to the peg.

Removing the micro:peg releases the wire.  The Mark 2 micro:pegs are simply popped out buy pushing on them from the back of the circuit board.

Because the connections made with micro:pegs are more secure than crocodile clips, the teacher can make up the circuits before the lesson and hand them out to the children to use.

If the children start to make a circuit but do not finish in time, their circuits can be collected in and handed back to be completed during later lesson.

See the video demo below.

The video above shows a 9 year old child giving a Mark 1 micro:peg demonstration.

The images below show a wire connected to the GND pin using a Mark 2 micro:peg.

micro:pegs can be printed in a range of colours to help children to connect wires to the correct terminals. 

Red and black pegs help to clarify the positive and negative terminals.

What problems are micro:pegs designed to eliminate?

A standard method of connecting components is to use croc to croc leads. These work well but when using them in my lessons I have experienced the following issues:

1. If not connected at right angles to the board clips slide along the edge strip causing short circuits or they slip off the edge strip completely.

2. Children can find it difficult to open the clips far enough to connect them at right angles to the board as recommended. 

3. Additional connections between the component and croc clip can result in short circuits and connection failure.

4. The extra connections add to the lengths of wiring which make the circuit more difficult to understand and follow. 

5. On occasions several components need to share a common GND terminal as with the traffic light model below. This can be difficult to do using crocodile clips.

The picture above shows three components sharing the same GND terminal.

How easy are they to use?

I have used micro:pegs extensively with children in National Curriculum Years 4 to 6 (8 to 11 years old). With a little bit of practice they found it much easier to attach and detach wires from the 4mm terminals using the pegs than they did using crocodile clips as demonstrated in the video above.

Some of the advantages to be gained from using the pegs are as follows:

1. The connections are secure and do not come undone accidentally or slide along the edge strip.

2. The peg connections do not cause short circuits.

3. The simplified wiring is easier to follow and understand.

4. It is possible to match the colour of the peg to the colour of the wire from the component so children can build their circuits by following a simple picture.

5. 'Bare' components such as an LED and wired components can be connected directly to the micro:bit's terminals.

6. Once made, the circuit is much neater.

7. Up to three wires can be connected to the same terminal.

Compare the two burglar alarm circuits below. They use exactly the same components and yet the one on the left using micro:pegs is much easier to make and to understand.

Manufacture and distribution

I have not sought to patent my invention. I am offering micro:pegs to commercial companies to make use of as they wish. My interest is to see my invention used in schools to make physical computing easier, particularly for children in primary schools.

Should a company wish to mass produce micro:pegs for large scale distribution then all I ask in return is that the invention is attributed to myself, Graham Hastings.

There are two models of micro:peg. The Mark 1 pegs illustrated in blue on the left below are designed for components with 'bare legs' or for single strand wire. They create a more secure, semi-permenant connection.

The Mark 2 pegs illustrated in orange on the right below are designed for multi-strand wire and are much simpler to use. You simply press them into the hole to trap the multi-strand wire. To disconnect them simply turn the micro:bit over and pop them out.

I have made two Tynkercad files available for export as .stl files ready for 3D printing.

The choice of colours is your own to make but red and black help to clarify positive and negative/GND terminals.

Mark 1    Use for a more secure semi-permanent connection.    https://www.tinkercad.com/things/j1LLddzHfJ2

Mark 2     Use for quick more temporary connection.    https://www.tinkercad.com/things/8XKPSXZqh8H-micropegmk2       

Mark 1 Mark 2

I leave the pegs attached after printing and snap them off as needed.

Mark 1 micro:pegs can be used to attach components with 'bare legs'.