LessonsLearned

During the project I have picked up a few lessons, hopefully this will help you a bit on the way, if nothing else writing them down will hopefully tech me something. For some people this is probably common sense, but then again it does not hurt to hear that every now and then either.

• Everything will take time. I often tried to find nifty solutions to many of my problems, but doing this takes time. It is fun and creative, but at the end of a day browsing for pipes or electrical components stops being fun after a while. Saving nickels and dimes to buy individual components cheaper is often not worthwhile the headache caused by trying to cut the small costs.

• Cables is a science. I cannot really tell you how much time I spent browsing for cables (of all things!). There are quite a few cables out there on the market and trying to find the right ones to use from an online catalog is not always easy when you have nothing to shoot for. At the end of the day I picked a few odd selections. I picked an outdoors CAT5 ethernet cable for connecting to my sensor islands and to the solenoid valves (this cable is not optimal, it is very non-flexible and really had a will of its own during handling). For the cables to the sensors I used cable from headphone extension cords (I really wanted flexible wiring easy to handle). I picked these after endless hours of thinking about UV protected wires (and what impact picking non-UV protected wires could have, will they be ok during a period of a few years or will they start breaking down immediately?), silicon coated wiring and other things with impact. But at the end of the day, most of the special wiring became to expensive and I picked some odd wires instead.

• As I used prototype boards for my circuits. This is a quick way of getting started and building boards. But do take the time to optimize the placement of circuits before starting to put everything together with the soldering iron, it is well worth while trying to keep the number of extra connections with wire down. The boards I used had chains of 3 holes connected. In order to optimize I scanned the back of the circuit board and printed them (in low contrast) on a paper and started drawing. I usually took anywhere between 3 and 10 iterations before finding a usable placement. If you know a good place that will print out your boards, this will be fantastic option for you as the experiment boards are really not that fun!

• I am not a plumber. I am not a plumber. It might seem as if this is a no brainer and to some extent it is. But be careful when mixing pipes. There are different pipes and dimensions for different types (or in reality purpose of the pipes). For instance I picked out a nice distributor pipe for connecting my solenoid valves, this has R22 connections on the end and R15 connections for each outlet. In all the stores I tried it was outright impossible to find anything that would go onto the R22 ends and then be connectable to a hose for water inlet.

• I was quite stressed about time when building some parts of the system. This did leave traces in terms of poor quality when connecting connectors (all to often I did mistakes in the connector numbers of the DB9 connectors for instance). Take your time and test each individual component one by one, this will make your comfort levels quite a bit lower when you connect everything later.

• Take the time to make proper connectors between the different boards and between the main box and all the sensors and sensor controllers. It is very nice to have the ability to disconnect and disassemble the individual parts during the process. This becomes very clear after everything is assembled and nothing is working. You need to have the ability of testing paths and components one by one to nail it down.

• For the mechanical works I picked myself up a Dremel. This is a fantastic tool for this and will make everything easier that has to do with milling and cutting. Lifesaver for me when I did the holes in the casings for the DB9's, the cutting and adjustments of the circuit boards for the different parts as well as building the sensors (cutting, adjusting and fixing up the sensor probes and holders).