I am no expert, repeat I am no expert.  Until recently I have painted my models using brush and Humbrol paints brought from my local model shop.  These models have been relatively small Stuart Turner stationary engines.

Last year when I saw the size of the frames for my POP steam wagon, I turned to spray cans.  It took a large can of satin black to do the frames.  I found that when spraying from the recommend distance more paint missed than went on the job.  While results were satisfactory it was clear to me that it would take a large number of cans to finish the POP.

I invested in an air brush and compressor and immediately found it much easier.  I used smooth Hammerite direct to rust metal paint.  Getting a good finish on large items such as the boiler was proving difficult so on advice from Phoenix Precision Paints I acquired a small spray gun.  This gave excellent results on the larger items but since it takes longer to clean I still use the air brush for the smaller items.

Practice is essential, and I can see a marked difference between the parts of my POP I painted first and those I have painted more recently. At some time I may have to strip and repaint my first attempts.  I have recently realised that adding the correct amount of thinners is key.  For airbrushing the paint needs to resemble ink.  If there is not enough thinners the paint will dry before it reaches the job.

Tools details of the equipment I use.

I have decided to paint as the build progresses.  This is a risky decision that I will need to keep under constant review.  I hope that the use of the Solidworks CAD system by MW will reduce the chance of modifications being needed.  It was reassuring to see the complete 3D CAD Model of the Burrell on the Supermodels 2 TV programme shown on Discovery Home and Leisure (It is the episode where they fit CCTV to the plane, about half way through there is a video tour of the MW factory).  Even so I have a nagging doubt that some of the more complex assemblies are better left unpainted until they have been checked against there mating parts.  

Three popular colour schemes that  I am considering 
 

example

This is my favourite. I may go and get some Dark Green Hammerite from B&Q and do a colour test.  All I need is a dustbin to paint.

This was my favourite but I have slight reservations as it is not very colourful.

example

I've seen some with the wheals red others the same maroon.  I prefer this as to my eye the red clashes with the maroon.