Temporary connector for gold contacts on arduino board

I recently acquired an Duinotech Leonardo Tiny (see below) which has gold contacts and holes for the GPIO pins. Unfortunately the typical breadboard jumper wires are too thin and don’t make great contact when inserted into the holes. Even when jumper wires push the board against the breadboard, the wire guage doesn’t make reliable contact with the metal contacts on the board.

I figure I either need a thicker wire or different type of connector.

Can anyone recommend a suitable connector for this style of contact for use in a breadboard?

I’d prefer not to solder onto the gold contacts.

This is the board:

Hi Ben,

Looks like perhaps those large pads were intended for alligator clips? It’s not something we sell so I’m not sure.

If it looks like they are the right size for aligator clips, perhaps the following might help?



Can you measure the size of the holes? None of the suppliers for that particular version seem to provide detailed PCB specifications.

There are two types of pin that I have used that are a step up from the typical Dupont wire size. The first one you could try is a pin from an extended header. They are 0.6mm square - the shape means it can jam into a round plated hole quite firmly. The second is the pin from a DB25 male plug - commonly found on old printer or modem cables. If you dismantle the plug you can recover 25 round 1mm pins with solder ends that are very useful as small ferrules, and might fit your board.

Hi All
If this is a board for experiment what is wrong with soldering some header pins into the holes. Continually inserting anything into the hole will ultimately damage the board, especially as it is probably at least 2 sided and the hole will be a “plated through” connection. A solid pin will need to be a firm fit which probably won’t happen. What is really needed is a bifurcated pin of some sort but the comments re damage still apply, there is not much gold thickness here.

Purchase some male pins would be easier. If you dismantle a “domestic” grade connector you are likely to get rolled pins which won’t stay round for very long. Machined pins would be better.
If you want to try the pin idea Jaycar have some 1.0mm pins, Cat no HP1250. A bit hard to tell what these exactly look like from the catalog but are not very expensive anyway. If you don’t have a Jaycar nearby Altronics carry a similar range of products.
I think D connector pins are 1.02mm but as the intended socket destination is a split springy device I expect this size is not super critical and some small variation could be tolerated. The data sheet I looked at does not indicate a tolerance figure for that dimension.

For an experimental device I still think soldered pins are the way to go. I say pins as sockets (especially the el cheapo ones commonly available) tend to open up and become unreliable after a while and intermittent test leads are something you can do without. If the socket is on the end of a wire it is easier to replace.
Cheers Bob