I knew at some point I would need to bite the bullet and attempt to weather one of my locos, bit of a daunting challenge considering the cost of an O gauge loco. I have practised on a couple of OO gauge locos before which had mixed results but the last one I was fairly happy with.  I chose my 37 as I had placed order on another which was being professionally weathered by Lee's Locos so I would have a comparison on my efforts.  

I first added the logos and numbers from Railtech, again not something I have had much experience with but found this to be fairly simple following pictures I found online. The wheel sets were stripped out of the bogies and I painted these by hand with Railmatch frame dirt and allowed to dry. I used a black grey wash on the side of the body concentrating on areas where dirt would build up, this was carefully removed using cotton buds. in the vents I used a mixture of black and earth brown weathering powder to get the desired effect, I also used this for areas where dirt would streak off the roof and down the side of the body. The powders are easy to use and if you are not getting the desired effect they are easy to remove so make weathering less stressful. 

I didn't want a heavy weathered effect on the body so I decided to remove this before painting the bogies and fuel tanks, with an air brush I sprayed these with a really thin mixture of paint so I could slowly build up to the level of weathering I wanted, I used a weathered black as the first layer then added areas of frame dirt on the front of the bogies following pictures of a real loco. The one area where I struggle to get the desired effect is the roof and around the exhaust ports, I decided to put a small amount of weathering powder on here and revisit as I get more confident with this area. 

With the level of weathering I was please with I coated the body with a layer of matt varnish to protect my efforts from handling, this also had an added effect of toning down the yellow nose areas making them look slightly faded. Thankfully depot plaques turned up which were put into place, I am happy on my first effort and will revisit the roof at some point.