Frome tabletop prototype to a usable home device

Question

I see a lot of questions dealing with going from prototype to production but I've got a more modest problem. I am building a couple of home automation devices for myself. I am able to build a table-top Arduino-based prototype using breadboard but I cannot find a good resource that would help me taking it from "table-top" to "usable" even if it means usable by myself. To give you an idea what I mean, here are the typical issues I am facing:

• "Right" way to connect things without breadboard. Arduino board has special headers for it, so what kind of plug does one use to outfit wires with in order to connect into them (short of sacrificing the test wires I have)? Should I just solder things together or should I use a small PCB (we are talking about a couple sensors and one or two resistors)
• "Right" way to outfit a long wire between Arduino and a sensor. Ideally, I would like to have a small 3-wire jack with female side connected to Arduino using short wires and male side at one end of a long cable which will have a sensor on the other end. Of course I can just solder things together but I wonder if there is a better way to do it.

And things like this - basically going from table-top design to a neat box one can use at home without naked wires sticking outside and ugly mess of stuff soldered together inside. :-)

Any tips would be highly appreciated.

Answer 1

If you have a relatively small number of parts that can fit on a board roughly the size of the Arduino you should consider using a prototyping shield like one of these:
https://www.adafruit.com/products/51
http://www.sparkfun.com/products/7914

If you were making a dozen or more devices it might be worthwile making a custom printed circuit board, but for just one or two it is easier and cheaper to simply solder your parts onto one of these proto boards that then plugs into your Arduino just like any other shield.

For connecting your sensor, mount a jack onto the proto board so that your wire can plug into it.

As for your case, there are many commercially available cases custom made for Arduinos or you could make one yourself depending on budget and how fancy you want it to be. People have used Tupperware containers, wooden boxes, mint tins; the list is endless.

Answer 2

Generally I would say for a home project, don't bother worrying too much about what the inside looks like, concentrate on the outside (i.e. case) since that's the only thing anyone else will see ;-) However you asked the question so:

For the case there are thousands of options out there, it's just a case of working out how much you want to spend and searching through them all.
For something that won't fit into an existing e.g. Hammond/Bud/etc case, you can get a custom metal one made for a reasonable price if you shop around. Custom plastic is too expensive for a one off.

For the wiring, any permanent/static stuff is fine with solder and maybe a dab of hot glue. For other stuff the common wire to board, board to board connectors are made by people like Molex, Tyco (TE Connectivity now I think), Samtec, and a few others I can't think of right now.
The Molex KK range is popular. 2.54mm unshrouded headers by Molex et al are everywhere, this is probably what your Arduino uses.
To make your own, you will need:

• A crimping tool (can be quite expensive)
• An insertion tool
• Some crimp contacts
• Some connector housings (see KK link)

All the links are for Molex KK stuff, but if you find another range just use google to find what you need e.g. "Tyco XXX insertion tool".

Other useful stuff includes heatshrink, heat gun and a hot glue gun.

If you look on the websites of the places I mentioned above you will find lots of different connector ranges and also advice on making your connectors up (how to crimp properly etc)
In the datasheet for whatever connector you find it will usually mention the recommended crimps/header compatible with it.