Nice. I like the using of parts from old things. How much work is it to get a CNC machine going? Someone on anther forum I visited has made their own and was cutting pieces from aluminium plate with good results.

In pinciple, not much. All you need is three movable axis, 3 stepper motors, and appropriate drivers and control software.

Of course in reality its much harder, you need a very sturdybframe, good accuracy on your linear bearings (as in: are they parallel? Are the surfaces constst width along the length etc.), pricey acme rod and ballnuts for the linear drive systems. And you have to make sure the thing is properly square when you build it.

I already have access to a laser cutter so I plan to laser cut the precision parts, and laser cut templates for the parts I can't cut by laser. I'm also planning on making it a bit of a junkbot, with as many free/recycled and inappropriate materials as possible. Hopefully get it done over the summer.

Which Nanos did you get? I'm going to need some for a project later this year.

I quite simply went for the cheapest presoldered Nano (with USB) I could find on ebay - http://www.ebay.co.uk/itm/171204215696

Also got 2 Pro Minis which need a USB to Serial adapter (that I already have) which only has the serial headers soldered - http://www.ebay.co.uk/itm/251336801022

I'll probably use the Nano for messing around since I can easily plug it into a breadboard, then use Pro Mini for anything more permanent. 

I also bought a bluetooth transceiver thing to maybe make it wireless.

Oh that is cheap. Will be interested to see if they are reliable, I've got a project in mind that will basically be installed and forgotten, so reliable boards are essential.

I'm going to have a look to see if there's any decent reviews of the cheap copies.

My general feeling on stuff like this is to go for the cheapest possible because I've seen plenty of items similar where, let's say the cheapest you can get one is for £2 there will be other sellers/websites selling the exact same item for upto around £10 where you'd be under the wrong assumption thinking it is actually better in any way. Not sure if that made any sense....!

Aye, unless you're buying from a reputable place that actually makes them then chances are you're buying the same cheap stuff.

The great thing with arduino is that it's open source, so the cheap ones are the same design. The only difference is the manufacturing - and China's pretty good at that part.

Not yet.  I am thinking of getting the Pi to Arduino bridge shield but the shield costs as much as the Pi and Arduino together.  I am actually starting to do a lot of what you are wanting to do.  The part I'm having a hard time with is deciding which automation software to use.  There are a lot of choices and some of them are pretty complicated!  If you decide on one let me know so I can check it out.  If we both use the same package we could potentially help each other.

I haven't even looked at any pre-built packages but I guess there's no harm in looking and trying a couple.

My plan was to totally make my own and a web interface to go with it. It may sound a bit silly but to a point I've already done quite a bit. I've got ways to turn on remote sockets over the Internet from my phone via a web page, easily check temperatures, activate motion detection etc.

The only thing I think might be more difficult is to make the software to possibly control central heating. To be able to set timers in a sensible fashion without using cronjobs etc.

What are your concerns with relays? I have a bunch that I was intending to use for lighting, have you had trouble with them?

Well then there you go!  Making your own might be the least complicated way of doing it!

I haven't had any issues with them but I'm yet to try them with any mains electricity. They're bloody easy to use and very useful though.

I do have concerns around safety, I could be being over cautious but I don't want to fudge something when it comes to mains. So, a list why I don't think relays are ideal for me.

1) Quality of relay - what makes a good relay? How much do properly decent ones cost with all the correct levels of insulation across circuits? Would I trust the ones I've bought from China? Probably not. (would I even be insured if I fit them myself and they caused a fire?)

2) Each relay will need cables running to whatever is controlling it.

3) I want a physical switch as well as being able to remotely control.

4) Switching states. Which carries on from 3... I want to be able to know whether something is on or off, or be able to calculate/work it out. If you use a relay and a physical switch I'm guessing it would need to be done in a similar fashion to having two switches for one light (upstairs/downstairs on stairs etc) which if I've worked the wiring out right you'd very quickly not know whether the relay being on/off would mean the light is on or off because of the use of the physical switch. I think this would make it impossible to turn a light on/off unless you already knew whether it was on or off. That may not seem like an issue but for example if I was out of the house and wanted to turn a light off, I want to be able to issue an "off" command. There could be a chance that the light is already off and I didn't know, with a relay I'd end up turning the light back on.


My current answer to this is LightwaveRF switches. So to answer the above

1) High quality products, much safer, tested etc. More expensive than relays though.

2) Simple to fit, just replaces your normal wall switch. Controlled wirelessly.

3) It is a physical switch that can be remotely controlled.

4) It can be issued with an "on" or an "off" command. So if you want to try and turn something off that is already off it stays off.

That was obviously to you!

Interesting.  Yeah I'm not crazy about having to wire everything up.  I am going to look into these lightwave things in a bit, it might make more sense for me to use them.

Thanks!

There's a number of other RF options out there.

Some that have a bit of a dummy switch which is battery powered and can go anywhere which acts as a remote and the RF received goes above the light fitting in the ceiling. There's even some lightbulbs out there that have it built in.

I wanted to easiest way to fit a remote controlled light and that was two screws and 2 or 3 wires with the LightwaveRF switches.

The switch I ordered should arrive in the next couple of days and I can have a play. Hopefully it does what I want. Or more so, I hope I can get the Arduino talking to it properly!

I have a set of the Phillips Hue bulbs.  Most of the Open Source Automation programs that I've messed with can control them.  But the downside is they are crazy expensive.  I don't think I'll be getting any more but who knows.

The switch I've bought is £25 (~$40) which I do feel is a bit expensive. Equivalents are probably cheaper in the US.

I've seen a bunch for ~$40, that seems to be the norm for them.  I think that's a little steep but it's the going rate!

Can't find the right thread, but this made me think of your temperature logging stuff. Also seems very interesting and has many very cool possibilities if all SD cards can be hacked like this..
http://www.bunniestudios.com/blog/?p=3554

Bet they work for the Feds.

Who /doesn't/ work for the feds?