Summer Postcards (word)

From the design sheets - I have produced several good idea's which I can build my concepts from.  However one which I have decided to carry on developing is too make the word 'Building' from using images of machinery/tools which I used over summer. 

Below are a few letters I have developed so far for my word ... see if you can see what machinery/tools I used - any feedback is welcomed!

Well thats some of the development so far using illustrators live trace and live paint tools ... very useful!  Feedback would be great, cheers!