Helping Third Hand

The Helping Third Hand is a nice tool to have because it can hold things in place while you solder things together. The teeth from these little grabbers however tend to byte into wires. So here’s a little quick tip. You can add heat shrink tubing to make it easier on things when grabbing onto them. Just add a piece to each grabber and apply heat. This adds a layer of protection and also makes things look nice. So now we can work with wires and avoid getting those byte marks.

Female JST Connectors

Before we get started on soldering, I want to point out something of a preference of mine. The JST extension cable has a male and female JST connector. So, why am I using a separate "stand-alone" female JST connector if there's one already wired to the cable?

Mainly because I think the SMT right angle connector is much more durable than the one wired to the extension cable. I've accidentally got the tip of the soldering iron too close to one of these and melted it – The black colored ones are a bit more resilient towards heat. Which ever you prefer, you're free to use the one you want.

The Slide Switch

This particular slide switch features three separate pins. They have 0.1" spacing and snap in nicely into a solderless breadboard. The middle pin is connected to either the left or right pin depending on which way the slider is pushed.

Secure The Switch

Go ahead and secure the slide switch onto one of the grabbers on the helping third hands with the pins facing out. We'll need only two of the three pins to make our slide switch JST adapter. So we can remove one of them, either the far left or right, just not the one in the middle! I like to use flush diagonal cutters so the cut is close to the subtrate.

Prep The Switch

The pins are bit longer than we need, so we can trim them short by cutting them in half using wire cutters. Next, we'll tin the two remaining pins by applying a bit of solder to them. You can do this by touching the pin with the tip of your soldering iron and a strand of solder. Just a small amount is suffice. By tinning the pins, it makes it easier to attach wires to them. Tinning pins and wires essentially make them "stickier". After that, we can take down the switch and set it aside. We'll work on the male JST connector next.

Male JST Connector

The JST extension cable has a male JST connector wired on one of the ends, so we can use it in our slide switch JST adapter. First, we'll need to determine the "right" size for our project. In this example, I'm making it for an enclosure that will house an Adafruit Feather. I typically make it about the size of the enclosure. Note, the size of the wire should accommodate for the switch and JST connectors. Rule of thumb is to make it longer than you think is necessary – You can always trim it shorter. Although you can add more to the wire if it's too short, that just adds more steps =]

Split Ground + Voltage Wires

Next, I'll separate the two wires since we will be attaching different components to each. Doesn't have to be all the way, just enough separation for the two connectors. By the way, black wire is ground (or negative) and the red one is voltage (or positive). 

Heat Shrink

Heat shrink is like the duct tape of electronics. It's mainly used for insulating exposed connections, but I tend to use it for grouping wires together – Avoids rats nests and keep things nice and neat! I recommend using the 3/32" size tubing for this project. It's the smallest size and works pretty well for the 24 AWG wires from the JST extension cable. Cut off a small piece and slip it over your wire.